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1.  MHC Haplotype Matching for Unrelated Hematopoietic Cell Transplantation 
PLoS Medicine  2007;4(1):e8.
Current criteria for the selection of unrelated donors for hematopoietic cell transplantation (HCT) include matching for the alleles of each human leukocyte antigen (HLA) locus within the major histocompatibility complex (MHC). Graft-versus-host disease (GVHD), however, remains a significant and potentially life-threatening complication even after HLA-identical unrelated HCT. The MHC harbors more than 400 genes, but the total number of transplantation antigens is unknown. Genes that influence transplantation outcome could be identified by using linkage disequilibrium (LD)-mapping approaches, if the extended MHC haplotypes of the unrelated donor and recipient could be defined.
Methods and Findings
We isolated DNA strands extending across 2 million base pairs of the MHC to determine the physical linkage of HLA-A, -B, and -DRB1 alleles in 246 HCT recipients and their HLA-A, -B, -C, -DRB1, -DQB1 allele-matched unrelated donors. MHC haplotype mismatching was associated with a statistically significantly increased risk of severe acute GVHD (odds ratio 4.51; 95% confidence interval [CI], 2.34–8.70, p < 0.0001) and with lower risk of disease recurrence (hazard ratio 0.45; 95% CI, 0.22–0.92, p = 0.03).
The MHC harbors genes that encode unidentified transplantation antigens. The three-locus HLA-A, -B, -DRB1 haplotype serves as a proxy for GVHD risk among HLA-identical transplant recipients. The phasing method provides an approach for mapping novel MHC-linked transplantation determinants and a means to decrease GVHD-related morbidity after HCT from unrelated donors.
A novel method of MHC haplotype matching provides a means to decrease graft-versus-host disease-related morbidity after transplantation from unrelated donors.
Editors' Summary
Graft rejection and graft-versus-host disease (GVHD) are feared complications of hematopoietic cell transplantation (HCT). GVHD can affect all parts of the body, and, if severe (grade III to IV out of a scale of IV), can lead to the death of the transplant recipient. GVHD or rejection of the graft occurs when there are differences in specific proteins involved in the immune response (known as HLA antigens) between donor and recipient that stimulate the immune reaction. GVHD and graft rejection occur most often in people who receive transplants from unrelated donors because, although when donors are matched to recipients matching is done for the most important HLA antigens known to be involved, it has not technically been possible to match for all possible antigens. However, the human genome is organized into segments or blocks of closely linked genetic variants that are inherited as “haplotypes” on the same DNA strand of a chromosome. Most of the genes that code for HLA antigens are physically located together in one part of the human genome, known as the MHC region. Currently three HLA markers from this region (HLA-A, -B, -DRB1) are matched when matching donors and recipients. If it were possible to better map the structure of this region, it would be possible to better match recipients and donors (especially unrelated donors) for the unidentified transplantation antigens and reduce the chance of recipients getting GVHD or rejecting their grafts.
Why Was This Study Done?
Current strategies to define MHC haplotype blocks look at, on average, a length of only 18,000 base pairs and hence cannot define extended MHC haplotypes. Previously, this group of researchers developed a method of defining the HLA-A, B, DR haplotypes in recipients and their HLA-matched unrelated transplant donors using high-quality DNA containing 2 million base pairs across the MHC region. They wanted see if using this technique might provide a way to better assess the risk recipients have of developing GVHD or of having recurrent disease.
What Did the Researchers Do and Find?
They studied 246 HCT recipients and their donors who had been matched for HLA-A, -B, -C, -DRB1, -DQB1 by current techniques. The recipients were having HCT for a variety of hematological cancers: acute lymphoid leukemia, acute myeloid leukemia, chronic myeloid leukemia, or myelodysplastic syndrome. They found that, using the new technique, 22% of the donor–recipient pairs were haplotype-mismatched. Taking various other factors into account, including age, and patient and donor gender, MHC haplotype mismatching was associated with an approximately four times greater risk of severe acute GVHD but with a lower risk of disease recurrence. The lower risk of recurrence is believed to be because transplanted cells do not only replace abnormal cancerous cells but also react against them and therefore decrease the chance of the cancer recurring; mismatched cells are known to be more stimulated to react against the cancerous cells.
What Do These Findings Mean?
The results here suggest that this new haplotype matching method can provide a way to assess the risk of GVHD after HCT from unrelated donors, and in future could be considered as a technique to match donors and recipients.
Additional Information.
Please access these Web sites via the online version of this summary at
• Medline Plus has a page of information on stem cell transplantation, including HCT
• The Anthony Nolan Trust holds one of the largest databases of unrelated donors in the world
• The National Cancer Institute has a page of questions and answers on HCT
• The Center for International Blood & Marrow Transplant Research describes outcomes research in transplantation
• The National Marrow Donor Program describes how HLA-typed unrelated donors are identified
• The World Marrow Donor Association is involved in facilitating stem cell donation across international boundaries
PMCID: PMC1796628  PMID: 17378697
2.  Klebsiella oxytoca bacteremia causing septic shock in recipients of hematopoietic stem cell transplant: Two case reports 
Cases Journal  2008;1:160.
Klebsiella oxytoca can cause various infectious complications in healthy as well as in immunocompromised individuals.
Case Presentations
Case 1: A 49 year old female with multiple myeloma received an autologous hematopoietic stem cell transplant in October 2005. Eight days following her autograft she developed septic shock caused by Klebsiella oxytoca bacteremia which was successfully treated with intravenous meropenem and gentamicin. Case 2: A 29 year old female with sickle cell anemia and severe aplastic anemia underwent an allogeneic hematopoietic stem cell transplant in July 2005. Seven months following her unsuccessful allograft, she developed septic shock due to Klebsiella oxytoca bacteremia caused by a urinary tract infection. The septic episode was successfully managed with intravenous meropenem and gentamicin. Both patients were treated at King Faisal Specialist Hospital and Research Centre in Riyadh, Saudi Arabia. To our knowledge, they are the first reports of Klebsiella oxytoca bacteremias and septic shocks in hematopoietic stem cell transplant recipients.
Klebsiella oxytoca should be considered as a possible cause of severe infections in recipients of various forms of hematopoietic stem cell transplantation. However, these infections may be complicated by bacteremias, septic shocks, systemic dysfunctions and even deaths if not managed promptly and appropriately.
PMCID: PMC2556667  PMID: 18801186
3.  Infections caused by mycobacterium tuberculosis in patients with hematological disorders and in recipients of hematopoietic stem cell transplant, a twelve year retrospective study 
Tuberculous infections in patients with hematological disorders and hematopoietic stem cell transplant vary in incidence, complications and response to treatment.
Methods and materials
A retrospective study of patients with various benign and malignant hematological disorders and recipients of hematopoietic stem cell transplant who were treated at Riyadh Armed Forces Hospital, Saudi Arabia between January 1991 and December 2002 and who developed tuberculous infections was conducted.
Tuberculous infections occurred in eighteen patients with hematological disorders and hematopoietic stem cell transplant. The main associated factors were: reduced immunity due to the primary hematological disorder, age more than 50 years and the administration of cytotoxic chemotherapy, steroids or radiotherapy. These infections frequently involved the lungs and predominantly occurred in males and in patients with chronic myeloproliferative disorders, myelodysplastic syndrome and acute myeloid leukemia. In patients treated with intravenous cytotoxic chemotherapy, tuberculous infections tended to occur earlier and also tended to be more disseminated compared to infections occurring in patients treated with oral chemotherapy. Anti-tuberculous treatment was given to 16 patients and it was successful in 15 of these patients.
Tuberculous infections cause significant morbidity and mortality in patients with various hematological disorders and in recipients of hematopoietic stem cell transplant. The early administration of anti-tuberculous therapy and compliance with drug treatment are associated with successful outcomes while delayed management, drug resistance and the presence of miliary infections are associated with poor prognosis and high mortality rates.
PMCID: PMC2200647  PMID: 18021401
4.  IFN-γ Mediates the Rejection of Haematopoietic Stem Cells in IFN-γR1-Deficient Hosts 
PLoS Medicine  2008;5(1):e26.
Interferon-γ receptor 1 (IFN-γR1) deficiency is a life-threatening inherited disorder, conferring predisposition to mycobacterial diseases. Haematopoietic stem cell transplantation (HSCT) is the only curative treatment available, but is hampered by a very high rate of graft rejection, even with intra-familial HLA-identical transplants. This high rejection rate is not seen in any other congenital disorders and remains unexplained. We studied the underlying mechanism in a mouse model of HSCT for IFN-γR1 deficiency.
Methods and Findings
We demonstrated that HSCT with cells from a syngenic C57BL/6 Ifngr1+/+ donor engrafted well and restored anti-mycobacterial immunity in naive, non-infected C57BL/6 Ifngr1−/− recipients. However, Ifngr1−/− mice previously infected with Mycobacterium bovis bacillus Calmette-Guérin (BCG) rejected HSCT. Like infected IFN-γR1-deficient humans, infected Ifngr1−/− mice displayed very high serum IFN-γ levels before HSCT. The administration of a recombinant IFN-γ-expressing AAV vector to Ifngr1−/− naive recipients also resulted in HSCT graft rejection. Transplantation was successful in Ifngr1−/− × Ifng−/− double-mutant mice, even after BCG infection. Finally, efficient antibody-mediated IFN-γ depletion in infected Ifngr1−/− mice in vivo allowed subsequent engraftment.
High serum IFN-γ concentration is both necessary and sufficient for graft rejection in IFN-γR1-deficient mice, inhibiting the development of heterologous, IFN-γR1-expressing, haematopoietic cell lineages. These results confirm that IFN-γ is an anti-haematopoietic cytokine in vivo. They also pave the way for HSCT management in IFN-γR1-deficient patients through IFN-γ depletion from the blood. They further raise the possibility that depleting IFN-γ may improve engraftment in other settings, such as HSCT from a haplo-identical or unrelated donor.
Claire Soudais and colleagues investigated the mechanism of rejection of hematopoietic stem cell transplants in patients with interferon-gamma receptor 1 (IFN-γR1) deficiency and show that IFN-γ is an anti-hematopoietic cytokine in vivo.
Editors' Summary
Normally, the body's immune system efficiently recognizes and kills bacteria and viruses, but in some rare inherited disorders (“primary immunodeficiencies”) part of the immune system works poorly or is missing. This leaves affected individuals susceptible to infections. People with one of these disorders—interferon-gamma receptor 1 (IFN- γR1) deficiency—are very susceptible to infections with mycobacteria. Except for Mycobacterium tuberculosis and M. leprae (which cause tuberculosis and leprosy, respectively), mycobacteria rarely cause human disease. However, most people with IFN-γR1 deficiency die during childhood from multiple, widespread mycobacterial infections, because IFN-γR1 deficiency disables a specific part of their immune system. When most bacteria enter the body, immune system cells called macrophages engulf and kill them, but mycobacteria actually multiply inside macrophages. This infection stimulates lymphocytes and other immune system cells to release IFN-γ, which binds to IFN-γR1 on uninfected macrophages, activates them, and recruits them to the infection site. Here, they form a “granuloma,” a mass of macrophages and activated lymphocytes that “walls off” the infection. Granuloma formation does not occur in patients with IFN-γR1 deficiency, so mycobacteria (including the usually benign tuberculosis vaccination strain M. bovis BCG) spread throughout the body with disastrous consequences.
Why Was This Study Done?
The only effective treatment for patients with IFN-γR1 deficiency is hematopoietic stem cell transplantation (HSCT). HSCs are the source of all the immune system cells, so transplantation of HSCs from a donor with a normal IFNGR1 gene can provide a patient who has IFN-γR1 deficiency with a new immune system that can combat mycobacterial infections. Unfortunately, in this particular immune deficiency, the new HSCs cannot engraft, even when the patient's own immune system is disabled before HSCT by intensive chemotherapy, and when the donor cells come from a close relative and are a good immunological match. In this study, the researchers have investigated why rejection is so common in IFN-γR1 deficiency using a mouse strain called C57BL/6 Ifngr1−/−—C57BL/6 denotes the genetic background of these mice and Ifngr1−/− indicates that, like human patients, these mice make no IFN-γR1.
What Did the Researchers Do and Find?
Ifngr1−/− mice, the researchers report, cannot control M. bovis BCG infections and do not form mature granulomas just like human patients with IFN-γR1 deficiency. Wild-type C57BL/6 (Ifngr1+/+) mice, however, rapidly control M. bovis BCG infections and form mature granulomas. Ifngr1+/+ HSC transplanted into mycobacteria-free Ifngr1−/− mice survived well and protected the mice against later mycobacterial challenge but Ifngr1−/− mice infected with M. bovis BCG before HSCT rejected the transplanted HSCs. Mycobacteria-infected Ifngr1−/− mice and human patients with IFN-γR1 deficiency have blood high levels of IFN-γ. Could this be responsible for HSCT rejection? To find out, the researchers expressed IFN-γ in uninfected Ifngr1−/− mice before HSCT. As in infected mice, these grafts failed. Conversely, transplanted HSCs survived when transplanted into Ifngr1−/− mice that had been genetically altered to express no IFN-γ, even when these mice were infected with M. bovis BCG before transplantation. Finally, when the researchers used antibodies (proteins made by the immune system that recognize specific molecules) to remove circulating IFN-γ from infected Ifngr1−/− mice, HSCT worked well in the animals with the lowest IFN-γ levels.
What Do These Findings Mean?
These findings indicate that in a mouse model of IFN-γR1 deficiency, high circulating IFN-γ concentrations drive the rejection of transplanted HSCs and prevent the development of antimycobacterial immunity, probably by directly killing the transplanted cells and/or stopping them multiplying. They also suggest how HSCT could be improved in patients with IFN-γR1 deficiency although, as with all animal studies, the situation in people might turn out to be very different. Importantly, antibodies that reduce circulating IFN-γ are already being used to treat other human immune diseases, so the clinical use of these antibodies in patients with IFN-γ deficiency before HSCT is feasible. Finally, the researchers speculate that the use of IFN-γ–depleting antibodies might be beneficial in other situations where HSCT often fails such as when a close relative is not available as a donor. However, this possibility will need to be thoroughly tested in mice before human clinical trials can be started.
Additional Information.
Please access these Web sites via the online version of this summary at
General information about primary immunodeficiencies is available from the US National Institute of Child Health and Human Development
Online Mendelian Inheritance in Man (OMIM) provides information about familial predisposition to mycobacterial disease
Wikipedia has pages on hematopoietic stem cell transplantation and on interferon-γ (note that Wikipedia is a free online encyclopedia that anyone can edit; available in several languages)
The Human Genetics of Infectious Diseases Lab focuses on the genetic basis of predicposition or resistance to infectious diseases in humans
PMCID: PMC2214797  PMID: 18232731
5.  Isoform-Specific Potentiation of Stem and Progenitor Cell Engraftment by AML1/RUNX1  
PLoS Medicine  2007;4(5):e172.
AML1/RUNX1 is the most frequently mutated gene in leukaemia and is central to the normal biology of hematopoietic stem and progenitor cells. However, the role of different AML1 isoforms within these primitive compartments is unclear. Here we investigate whether altering relative expression of AML1 isoforms impacts the balance between cell self-renewal and differentiation in vitro and in vivo.
Methods and Findings
The human AML1a isoform encodes a truncated molecule with DNA-binding but no transactivation capacity. We used a retrovirus-based approach to transduce AML1a into primitive haematopoietic cells isolated from the mouse. We observed that enforced AML1a expression increased the competitive engraftment potential of murine long-term reconstituting stem cells with the proportion of AML1a-expressing cells increasing over time in both primary and secondary recipients. Furthermore, AML1a expression dramatically increased primitive and committed progenitor activity in engrafted animals as assessed by long-term culture, cobblestone formation, and colony assays. In contrast, expression of the full-length isoform AML1b abrogated engraftment potential. In vitro, AML1b promoted differentiation while AML1a promoted proliferation of progenitors capable of short-term lymphomyeloid engraftment. Consistent with these findings, the relative abundance of AML1a was highest in the primitive stem/progenitor compartment of human cord blood, and forced expression of AML1a in these cells enhanced maintenance of primitive potential both in vitro and in vivo.
These data demonstrate that the “a” isoform of AML1 has the capacity to potentiate stem and progenitor cell engraftment, both of which are required for successful clinical transplantation. This activity is consistent with its expression pattern in both normal and leukaemic cells. Manipulating the balance of AML1 isoform expression may offer novel therapeutic strategies, exploitable in the contexts of leukaemia and also in cord blood transplantation in adults, in whom stem and progenitor cell numbers are often limiting.
The truncated "a" isoform of AML1 is shown to have the capacity to potentiate stem and progenitor cell engraftment, both of which are required for successful clinical transplantation.
Editors' Summary
Blood contains red blood cells (which carry oxygen round the body), platelets (which help the blood to clot), and white blood cells (which fight off infections). All these cells, which are regularly replaced, are derived from hematopoietic stem cells, blood-forming cells present in the bone marrow. Like all stem cells, hematopoietic stem cells self-renew (reproduce themselves) and produce committed progenitor cells, which develop into mature blood cells in a process called hematopoiesis. Many proteins control hematopoiesis, some of which are called transcription factors; these factors bind to DNA through their DNA-binding domain and then control the expression of genes (that is, how DNA is turned into proteins) through particular parts of the protein (their transcription regulatory domains). An important hematopoietic transcription factor is AML1—a protein first identified because of its involvement in acute myelogenous leukemia (AML, a form of blood cancer). Mutations (changes) in the AML1 gene are now known to be present in other types of leukemia, which are often characterized by overproliferation of immature blood cells.
Why Was This Study Done?
Because of AML1′s crucial role in hematopoiesis, knowing more about which genes it regulates and how its activity is regulated could provide clues to treating leukemia and to improving hematopoietic cell transplantation. Many cancer treatments destroy hematopoietic stem cells, leaving patients vulnerable to infection. Transplants of bone marrow or cord blood (the cord that links mother and baby during pregnancy contains peripheral blood stem cells) can replace the missing cells, but cord blood in particular often contains insufficient stem cells for successful transplantation. It would be useful, therefore, to expand the stem cell content of these tissues before transplantation. In this study, the researchers investigated the effect of AML1 on self-renewal and differentiation of hematopoietic stem and progenitor cells in the laboratory (in vitro) and in animals (in vivo). In particular, they have asked how two isoforms (closely related versions) of AML1 affect the ability of these cells to grow and differentiate (engraft) in mice after transplantation.
What Did the Researchers Do and Find?
The researchers artificially expressed AML1a and AML1b (both isoforms contain a DNA binding domain, but only AML1b has transcription regulatory domains) in mouse hematopoietic stem and progenitor cells and then tested the cells' ability to engraft in mice. AML1a-expressing cells engrafted better than unaltered cells and outgrew unaltered cells when transplanted as a mixture. AML1b-expressing cells, however, did not engraft. In vitro, AML1a-expressing cells grew more than AML1b-expressing cells, whereas differentiation was promoted in AML1b-expressing cells. To investigate whether the isoforms have the same effects in human cells, the researchers measured the amount of AML1a and AML1b mRNA (the template for protein production) made by progenitor cells in human cord blood. Although AML1b (together with AML1c, an isoform with similar characteristics) mRNA predominated in all the progenitor cell types, the relative abundance of AML1a was greatest in the stem and progenitor cells. Furthermore, forced expression of AML1a in these cells improved their ability to divide in vitro and to engraft in mice.
What Do These Findings Mean?
These findings indicate that AML1a expression increases the self-renewal capacity of hematopoietic stem and progenitor cells and consequently improves their ability to engraft in mice, whereas AML1b expression encourages the differentiation of these cell types. These activities are consistent with the expression patterns of the two isoforms in normal hematopoietic cells and in leukemic cells—the mutated AML made by many leukemic cells resembles AML1a. Because the AML1 isoforms were expressed at higher than normal levels in these experiments, the physiological relevance of these findings needs to be confirmed by showing that normal levels of AML1a and AML1b produce similar results. Nevertheless, these results suggest that manipulating the balance of AML1 isoforms made by hematopoietic cells might be useful clinically. In leukemia, a shift toward AML1b expression might slow the proliferation of leukemic cells and encourage their differentiation. Conversely, in cord blood transplantation, a shift toward AML1a expression might improve patient outcomes by expanding the stem and progenitor cell populations.
Additional Information.
Please access these Web sites via the online version of this summary at
Wikipedia has pages on hematopoiesis and hematopoietic stem cells (note: Wikipedia is a free online encyclopedia that anyone can edit; available in several languages)
The US National Cancer Institute has a fact sheet on bone marrow and peripheral blood stem cell transplantation (in English and Spanish) and information for patients and professionals on leukemia (in English)
The American Society of Hematology provides patient information about blood diseases, including information on bone marrow and stem cell transplantation
PMCID: PMC1868041  PMID: 17503961
6.  Prediction of Graft-Versus-Host Disease in Humans by Donor Gene-Expression Profiling 
PLoS Medicine  2007;4(1):e23.
Graft-versus-host disease (GVHD) results from recognition of host antigens by donor T cells following allogeneic hematopoietic cell transplantation (AHCT). Notably, histoincompatibility between donor and recipient is necessary but not sufficient to elicit GVHD. Therefore, we tested the hypothesis that some donors may be “stronger alloresponders” than others, and consequently more likely to elicit GVHD.
Methods and Findings
To this end, we measured the gene-expression profiles of CD4+ and CD8+ T cells from 50 AHCT donors with microarrays. We report that pre-AHCT gene-expression profiling segregates donors whose recipient suffered from GVHD or not. Using quantitative PCR, established statistical tests, and analysis of multiple independent training-test datasets, we found that for chronic GVHD the “dangerous donor” trait (occurrence of GVHD in the recipient) is under polygenic control and is shaped by the activity of genes that regulate transforming growth factor-β signaling and cell proliferation.
These findings strongly suggest that the donor gene-expression profile has a dominant influence on the occurrence of GVHD in the recipient. The ability to discriminate strong and weak alloresponders using gene-expression profiling could pave the way to personalized transplantation medicine.
The donor gene expression profile appears to have a dominant influence on the occurrence of graft-versus-host disease in the recipient.
Editors' Summary
Human blood contains red blood cells, white blood cells, and platelets, which carry oxygen throughout the body, fight infections, and help blood clot, respectively. Normally, blood-forming (hematopoietic) stem cells in the bone marrow (and their offspring, peripheral blood stem cells) continually provide new blood cells. Tumors that arise from the bone marrow (such as leukemia and lymphoma, two types of hematopoietic tumor) are often treated by a bone marrow or peripheral blood stem cell transplant from a healthy donor to provide new blood-forming stem cells, as a follow-up to chemotherapy or radiotherapy designed to eradicate as much of the tumor as possible. This procedure is called allogeneic hematopoietic cell transplantation (AHCT)—the word allogeneic indicates that the donor and recipient are not genetically identical. When solid organs (for example, kidneys) are transplanted, the recipient's immune system can recognize alloantigens (proteins that vary between individuals) on the donor organ as foreign and reject it. To reduce the risk of rejection, the donor and recipient must have identical major histocompatibility complex (MHC) proteins. MHC matching is also important in AHCT but for further reasons. Here, donor T lymphocytes (a type of white blood cell) can attack the skin and other tissues of the host. This graft versus host disease (GVHD) affects many people undergoing AHCT despite MHC matching either soon after transplantation (acute GVHD) or months later (chronic GVHD). As an aside, the transplant may also act against the tumor itself—this is known as a graft versus leukemia effect.
Why Was This Study Done?
GVHD can usually be treated with drugs that damp down the immune system (immunosuppressive drugs), but it would be preferable to avoid GVHD altogether. Indeed, GVHD continues to be the leading cause of nonrelapse mortality following AHCT. Unfortunately, what determines who will develop GVHD after MHC-matched AHCT is unclear. Although GVHD only develops if there are some mismatches in histocompatibility antigens between the donor and host, it does not inevitably develop. Until now, scientists have mainly investigated whether differences between ACHT recipients might explain this observation. But, in this study, the researchers have examined the donors instead to see whether differences in their immune responses might make some donors stronger “alloresponders” than others and consequently more likely to cause GVHD.
What Did the Researchers Do and Find?
The researchers used a molecular biology technique called microarray expression profiling to examine gene expression patterns in the T lymphocytes of peripheral blood stem cell donors. From these patterns, they identified numerous genes whose expression levels discriminated between donors whose MHC-identical transplant recipient developed GVHD after AHCT (GVHD+ donors) and those whose recipient did not develop GVHD (GVHD− donors). The researchers confirmed that the expression levels of 17 of these genes discriminated between GVHD+ and GVHD− donors using a second technique called quantitative reverse transcriptase polymerase chain reaction. Many of these genes are involved in TGF-β signaling (TGF-β is a protein that helps to control the immune system), cell growth, or proliferation. The researchers also identified four gene pairs that interacted with each other to determine the likelihood that a given donor would induce GVHD. Finally, the researchers computationally retested their data and showed that the measurement of expression levels of each of these genes and of the four interacting gene pairs could correctly identify a donor sample likely to cause GVHD in up to 80% of samples.
What Do These Findings Mean?
These findings provide the first evidence that the donor's gene expression profile influences the development of GVHD in the recipient after AHCT. The researchers suggest that a “dangerous donor” (strong alloresponder) is a key factor in determining whether GVHD occurs after AHCT and propose that gene expression profiling of donor T lymphocytes might identify those donors likely to cause GVHD. Before this approach can be used to reduce the incidence of GVHD after AHCT, these findings need to be confirmed in many more donors. Also, the development of a test that is accurate enough for clinical use—one that does not miss dangerous donors but does not discard too many safe donors—may require the identification of larger groups of interacting genes. But, if it survives further investigation, the concept of a dangerous donor could represent an important advance in transplantation medicine, one that could help clinicians select low-risk donors for AHCT and tailor patients' immunosuppressive drug regimens according to their donor-determined risk of GVHD.
Additional Information.
Please access these Web sites via the online version of this summary at
• The National Marrow Donor Program provides information for patients and physicians on all aspects of hematopoietic stem cell transplantation, including GVHD
• The MedlinePlus encyclopedia has pages on bone marrow transplants, GVHD and transplant rejection
• The US National Cancer Institute has a factsheet on bone marrow and peripheral blood stem cell transplantation
PMCID: PMC1796639  PMID: 17378698
This paper addresses an important pre-requisite for promoting child health; namely the promotion of sound child development.
The study aimed at identifying factors affecting child development in Madinah, Saudi Arabia.
A cross-sectional study with a multi-stage stratified random sample of children.
Well-baby clinics of the primary health care centers in urban and rural areas of the Madinah region, North-western Saudi Arabia.
A sample of 1219 “normal” children below the age of six.
Tools used for the study were the modified and translated Denver Revised-Pre-screening Developmental Questionnaire (R-PDQ), and the Denver Developmental Screening Test (DDST) kit together with a social questionnaire. Logistic Regression analysis was used to show any significant association(s) between the study variables and the 104 developmental items in the R-PDQ.
Eight variables were found to be strongly associated with each of the developmental items. Mothers’ education was found to be significantly associated with 21 developmental items. Number of children in the household was next to mothers’ education in its association with child development. Place of residence and gender were found to be significantly associated with seven and one abilities respectively.
Findings emphasized the importance of girls and mothers’ education as an aid in stimulating the development of their children and enabling mothers to prepare children for school. Adequate birth interval, and prolonged breastfeeding are recommended to enable mothers to care for their children, communicate with them and foster sound development. Scrutinizing the child's home environment and involving parents in the developmental progress of their children are also considered important. More stimulation and educational play are recommended for rural children and male urban children.
PMCID: PMC3437101  PMID: 23008601
Child development; R-PDQ; Madina; Saudi Arabia
8.  Factors Associated With Parental Activation in Pediatric Hematopoietic Stem Cell Transplant 
Patient activation, the extension of self-efficacy into self-management, is an essential component of effective chronic care. In pediatric populations, caregiver activation is also needed for proper disease management. This study investigates the relationships between parental activation and other characteristics of parent–child dyads (N = 198) presenting for pediatric hematopoietic stem cell transplant. Parental activation concerning their child’s health was assessed using the Parent Patient Activation Measure (Parent-PAM), a modified version of the well-validated Patient Activation Measure (PAM). Using hierarchical linear regression and following the Belsky process model for determining parenting behaviors, a multivariate model was created for parental activation on behalf of their child that showed that the parent’s age, rating of their own general health, self-activation, and duration of the child’s illness were significantly related to Parent-PAM score. Our findings characterize a potentially distinct form of activation in a parent–child cohort preparing for a demanding clinical course.
PMCID: PMC4160822  PMID: 22203645
cancer; oncology; hematopoietic stem cell transplant (HSCT); children; patient activation; Patient Activation Measure
9.  Can Routine Commercial Cord Blood Banking Be Scientifically and Ethically Justified? 
PLoS Medicine  2005;2(2):e44.
Background to the debate: Umbilical cord blood—the blood that remains in the placenta after birth—can be collected and stored frozen for years. A well-accepted use of cord blood is as an alternative to bone marrow as a source of hematopoietic stem cells for allogeneic transplantation to siblings or to unrelated recipients; women can donate cord blood for unrelated recipients to public banks. However, private banks are now open that offer expectant parents the option to pay a fee for the chance to store cord blood for possible future use by that same child (autologous transplantation.)
Private banks offer expectant parents the option to pay a fee for the chance to store cord blood for possible future use by the child. The practice is controversial, for scientific and ethical reasons
PMCID: PMC549592  PMID: 15737000
10.  Does consanguinity increase the risk of bronchial asthma in children? 
Annals of Thoracic Medicine  2008;3(2):41-43.
There is a high prevalence of consanguinity and bronchial asthma in Saudi Arabia. The objective of this study is to explore the effect of parental consanguinity on the occurrence of bronchial asthma in children. The study sample was determined by multistage random probability sampling of Saudi households. The families with at least one child with asthma were matched with an equal number of families randomly selected from a list of families with healthy children, the latter families being designated as controls. There were 103 families with children having physician-diagnosed bronchial asthma, matched with an equal number of families with no children with asthma. This resulted in 140 children with bronchial asthma and 295 children from controls. The age and gender distribution of the children with bronchial asthma and children from controls were similar. There were 54/103 (52.4%) and 61/103 (59.2%) cases of positive parental consanguinity in asthmatic children and children from controls respectively (P = 0.40). Analysis of consanguinity status of the parents of children with asthma and parents among controls indicates that 71/140 (51%) of the children with asthma and 163/295 (55.3%) of the children from controls had positive parental overall consanguinity (P = 0.43). The results of this study suggest that parental consanguinity does not increase the risk of bronchial asthma in children.
PMCID: PMC2700455  PMID: 19561903
Bronchial asthma; consanguinity; Saudi Arabia
11.  Complete genome sequencing and phylogenetic analysis of dengue type 1 virus isolated from Jeddah, Saudi Arabia 
Virology Journal  2015;12:1.
Dengue viruses (DENVs) are mosquito-borne viruses which can cause disease ranging from mild fever to severe dengue infection. These viruses are endemic in several tropical and subtropical regions. Multiple outbreaks of DENV serotypes 1, 2 and 3 (DENV-1, DENV-2 and DENV-3) have been reported from the western region in Saudi Arabia since 1994. Strains from at least two genotypes of DENV-1 (Asia and America/Africa genotypes) have been circulating in western Saudi Arabia until 2006. However, all previous studies reported from Saudi Arabia were based on partial sequencing data of the envelope (E) gene without any reports of full genome sequences for any DENV serotypes circulating in Saudi Arabia.
Here, we report the isolation and the first complete genome sequence of a DENV-1 strain (DENV-1-Jeddah-1-2011) isolated from a patient from Jeddah, Saudi Arabia in 2011. Whole genome sequence alignment and phylogenetic analysis showed high similarity between DENV-1-Jeddah-1-2011 strain and D1/H/IMTSSA/98/606 isolate (Asian genotype) reported from Djibouti in 1998. Further analysis of the full envelope gene revealed a close relationship between DENV-1-Jeddah-1-2011 strain and isolates reported between 2004–2006 from Jeddah as well as recent isolates from Somalia, suggesting the widespread of the Asian genotype in this region.
These data suggest that strains belonging to the Asian genotype might have been introduced into Saudi Arabia long before 2004 most probably by African pilgrims and continued to circulate in western Saudi Arabia at least until 2011. Most importantly, these results indicate that pilgrims from dengue endemic regions can play an important role in the spread of new DENVs in Saudi Arabia and the rest of the world. Therefore, availability of complete genome sequences would serve as a reference for future epidemiological studies of DENV-1 viruses.
PMCID: PMC4310205  PMID: 25591713
Dengue virus; Full genome; Phylogenetic analysis; Diversity; Jeddah; Saudi Arabia
12.  Saudi mothers' preferences about breaking bad news concerning newborns: a structured verbal questionnaire 
BMC Medical Ethics  2011;12:15.
Breaking bad news (BBN) to parents whose newborn has a major disease is an ethical dilemma. In Saudi Arabia, BBN about newborns is performed according to the parental preferences that have been reported from non-Arabic/non-Islamic countries. Saudi mothers' preferences about BBN have not yet been studied. Therefore, we aimed to elicit the preferences of Saudi mothers about BBN concerning newborns.
We selected a convenience sample of 402 Saudi mothers, aged 18-50 years, who had no previous experience with BBN. We selected them via a simple number-randomization scheme from the premises of a level III Saudi hospital between October of 2009 and January of 2011. We used a hypothetical situation (BBN about trisomy 21) to elicit their preferences about BBN concerning newborns via a structured verbal questionnaire composed of 12 multiple-choice questions. We expressed their preferences as percentages (95% confidence interval), and we used the Kendall's W test (W) to assess the degree of agreement in preferences.
The Saudi mothers preferred that BBN be conducted with both parents together (64% [60-69]), albeit with weak levels of agreement (W = 0.29). They showed moderate agreement in their preferences that BBN should be conducted early (79% [75-83], W = 0.48), in detail (81% [77-85], W = 0.52), in person (88% [85-91], W = 0.58), and in a quiet setting (86% [83-90], W = 0.53). With extremely weak agreement, they preferred to have a known person present for support during BBN (56% [51-61], W = 0.01), to have close bodily contact with their babies (66% [61-70], W = 0.10), and to have no another patients present (64% [59-68], W = 0.08). They showed moderate levels of agreement in their desires to detail, in advance, their preferences about process of BBN by giving a reversible, written informed consent that could be utilized for guidance, if needed (80% [76-84], W = 0.36).
In our experience, Saudi mothers' preferences about BBN concerning newborns are varied, suggesting that a "one-size-fits-all" approach is inappropriate. A reversible, written informed consent detailing their preferences about BBN that would be kept in their medical records and utilized for guidance, if needed, may be the best solution, given this level of diversity. These findings merit further study.
PMCID: PMC3175465  PMID: 21861876
13.  Allogeneic Stem Cell Transplantation for CML Resistant to Tyrosine Kinase Inhibitors 
Clinical lymphoma, myeloma & leukemia  2011;11(Suppl 1):S96-S100.
Allogeneic hematopoietic stem cell transplantation (HSCT) is well established as a potentially curative treatment for patients with CML. The success of imatinib and other tyrosine kinase inhibitors (TKI) as initial therapy has changed the treatment paradigm in this disease. Allogeneic hematopoietic transplants are now reserved for patients failing to respond optimally to TKI treatment. Patients failing to have an optimal response to imatinib may respond to a second generation TKI, dasatinib or nilotinib, and many achieve major or complete molecular and cytogenetic responses. The indication for allogeneic HSCT vs. continued second line therapy is not well defined and is the subject of ongoing study. There has been continued progress in reducing the toxicity and risks of HSCT with development of reduced intensity regimens; transplants can be routinely performed in patients up to age 75 who are in fair general medical condition. Transplants from unrelated donors have improved, with survival similar that achieved with matched siblings. Results with haploidentical and cord blood transplants have markedly improved, and should be considered for patients lacking a matched donor. Allogeneic hematopoietic transplants have the best chance to be curative in patients with chronic phase that is under hematologic control with 80% disease free survival; patients progressing to accelerated phase or blast crisis have a much poorer prognosis. Thus, HSCT should be considered for patients with imatinib failure. Patients receiving second line TKI therapy need to be closely monitored, and referred for transplantation if a complete cytogenetic response and major molecular response is not achieved. HSCT should be performed if feasible in patients without a continued response to TKI treatment.
PMCID: PMC3226776  PMID: 22035758
14.  Haploidentical Hematopoietic Stem-Cell Transplantation in Adults 
Bone Marrow Research  2011;2011:303487.
Haploidentical hematopoietic stem-cell transplantation is an alternative transplant strategy for patients without an HLA-matched donor. Still, only half of patients who might benefit from transplantation are able to find an HLA-matched related or unrelated donor. Haploidentical donor is readily available for many patients in need of immediate stem-cell transplantation. Historical experience with haploidentical stem-cell transplantation has been characterised by a high rejection rate, graft-versus-host disease, and transplant-related mortality. Important advances have been made in this field during the last 20 years. Many drawbacks of haploidentical transplants such as graft failure and significant GVHD have been overcome due to the development of new extensive T cell depletion methods with mega dose stem-cell administration. However, prolonged immune deficiency and an increased relapse rate remain unresolved problems of T cell depletion. New approaches such as partial ex vivo or in vivo alloreactive T cell depletion and posttransplant cell therapy will allow to improve immune reconstitution in haploidentical transplants. Results of unmanipulated stem-cell transplantation with using ATG and combined immunosuppression in mismatched/haploidentical transplant setting are promising. This paper focuses on recent advances in haploidentical hematopoietic stem-cell transplantation for hematologic malignancies.
PMCID: PMC3199934  PMID: 22046559
15.  Prevalence of Allergic Disorders among Primary School-Aged Children in Madinah, Saudi Arabia: Two-Stage Cross-Sectional Survey 
PLoS ONE  2012;7(5):e36848.
There are limited data on the epidemiology of allergic disorders in Saudi Arabia. Such data are needed for, amongst other things, helping to plan service provision at a time when there is considerable investment taking place in national healthcare development. We sought to estimate the prevalence of atopic eczema, allergic rhinitis and asthma in primary school children in Madinah, Saudi Arabia.
Methods and Findings
We conducted a two-stage cross-sectional survey of schoolchildren in Madinah. Children were recruited from 38 randomly selected schools. Questionnaires were sent to the parents of all 6,139 6–8 year old children in these schools. These parental-completed questionnaires incorporated questions from the International Study of Asthma and Allergies in Childhood (ISAAC), which had previously been validated for use in Arab populations. We undertook descriptive analyses, using the Generalized Estimating Equation (GEE) to calculate 95% confidence intervals. The overall response rate was 85.9% (n = 5,188), 84.6% for girls and 86.2% for boys, respectively. Overall, parents reported symptoms suggestive of a history of eczema in 10.3% (95%CI 9.4, 11.4), rhinitis in 24.2% (95%CI 22.3, 26.2) and asthma in 23.6% (95%CI 21.3, 26.0) of children. Overall, 41.7% (95%CI 39.1, 44.4) of children had symptoms suggestive of at least one allergic disorder, with a substantial minority manifesting symptoms indicative of co-morbid allergic disease. Comparison of these symptom-based prevalence estimates with reports of clinician-diagnosed disease suggested that the majority of children with eczema and asthma had been diagnosed, but only a minority (17.4%) of children had been diagnosed with rhinitis. International comparisons indicated that children in Madinah have amongst the highest prevalence of allergic problems in the world.
Symptoms indicative of allergic disease are very common in primary school-aged children in Madinah, Saudi Arabia, with figures comparable to the highest risk regions in the world.
PMCID: PMC3355178  PMID: 22615824
16.  Umbilical Cord Blood: An Evolving Stem Cell Source for Sickle Cell Disease Transplants 
Allogeneic hematopoietic stem cell transplantation has proven benefit in controlling sickle cell disease-related vasculopathy and organ damage. However, the difficulty in finding HLA-matched donors in the family or registry is a therapeutic limitation. Umbilical cord blood transplantation allows for more mismatching from the graft-versus-host disease perspective and this donor pool is expandable with effort and education. Successful unrelated donor cord blood transplantation (UCBT) can overcome this limitation and formal trials of UCBT merit consideration in this disorder.
Allogeneic hematopoietic stem cell transplantation has proven benefit in controlling sickle cell disease-related vasculopathy and organ damage. Myeloablative matched sibling donor cord transplants have excellent outcomes in sickle cell disease. Unrelated donor transplant options are often deferred because of a lack of suitable human leukocyte antigen-matched donors, a problem especially relevant to minority populations. Umbilical cord blood transplantation allows for more mismatching from the graft-versus-host disease perspective and the donor pool is expandable with effort and education. Drawbacks such as increased rates of graft rejection, a fixed cell dose, delayed immune reconstitution, and transplant-related mortality have deterred unrelated cord transplant efforts. However, the transplant community continues to make enormous strides in this transplant realm in areas of immunogenetics, stem cell expansion, conditioning regimens, and supportive care. This has allowed the development of new studies that are currently ongoing, exploring ways to make cord blood transplantation successful and safer. The goal is to make unrelated donor cord blood transplantation for sickle cell disease merit early consideration in patients who stand to benefit from this approach.
PMCID: PMC3667562  PMID: 23580541
17.  Tolerogenic effect of non-inherited maternal antigens in hematopoietic stem cell transplantation 
Major histocompatibility complex antigens that provoke severe transplant reactions are referred to as the human leukocyte antigen (HLA) in human and as the H-2 in mice. Even if the donor and recipient are HLA-identical siblings, graft-versus-host reactions have been linked to differences in the minor histocompatibility antigen. As the chance of finding an HLA-identical sibling donor is only 25%, attention has been focused on using alternative donors. An HLA-mismatched donor with non-inherited maternal antigens (NIMA) is less immunogenic than that with non-inherited paternal antigens, because the contact between the immune systems of the mother and child during pregnancy affects the immune response of the child against NIMA. However, the immunologic effects of developmental exposure to NIMA are heterogeneous, and can be either tolerogenic or immunogenic. We recently have devised a novel method for predicting the tolerogenic effect of NIMA. In this review, we overview the evidence for the existence of the NIMA tolerogenic effect, the possible cellular and molecular basis of the phenomenon, and its utilization in hematopoietic stem cell transplantation. We suggest a future direction for the safe clinical use of this phenomenon, fetomaternal tolerance, in the transplantation field.
PMCID: PMC3360462  PMID: 22654885
NIMA; tolerance; acute GVHD; hematopoietic stem cell transplantation
18.  Assessment of health-related quality of life in pediatric hematopoietic stem cell transplant recipients: progress, challenges and future directions 
This article provides an overview of health-related quality of life (HRQoL) assessments in pediatric hematopoietic stem cell transplants, focusing on the relationship between child and parent proxy ratings of the child’s HRQoL and how measurement of HRQoL may be incorporated into clinical decision-making. Parent and child ratings of the child’s health may be affected differently by unequal access to and incongruent understanding of available information, as well as the effect of age difference on interpretation. In particular, parents and children may experience the impact of clinical events on HRQoL very differently. The recent US Federal emphasis on ‘patient-centeredness’ has helped fuel the development and application of more clinically functional and low-burden HRQoL measures. Future work in pediatric hematopoietic stem cell transplants must seek to capture the experiences and perceptions of all those involved.
PMCID: PMC4160229  PMID: 23570432
Child Health Ratings Inventories; health-related quality of life; hematopoietic stem cell transplant; parent–child difference; Patient-Reported Outcomes Measurement Information System™
19.  First Insight into the Population Structure of Mycobacterium tuberculosis in Saudi Arabia▿ †  
Journal of Clinical Microbiology  2007;45(8):2467-2473.
This study constitutes a first attempt to describe the genetic population structure and drug resistance of the tubercle bacilli circulating in Saudi Arabia. A total of 1,505 clinical isolates of M. tuberculosis, isolated between 2002 and 2005 from seven regions of Saudi Arabia, were studied. The sample studied showed a male-to-female sex ratio of 1.27, with half of the cases among foreign-born individuals and 47% within the 21- to 40-year-old age group; a total resistance rate of 19.7%; and multiple drug resistance of 4.5%. Upon spoligotyping, a total of 387 individual patterns were obtained (clustering rate, 86.4%; 182 clusters containing between 2 and 130 isolates per cluster). A total of 94% of the strains matched the spoligotype patterns in an international database. Nearly 81% of the isolates in this study belonged to established phylogeographic clades: Central Asian (CAS), 22.5%; ill-defined T clade, 19.5%; East African-Indian (EAI), 13.5%; Haarlem, 7.5%; Latin American-Mediterranean, 7.2%; Beijing, 4.4%; Manu, 2.7%; X, 0.9%; and Bovis, 0.9%. Two clonal complexes with unique spoligotyping signatures (octal codes 703777707770371 and 467777377413771) specific to Saudi Arabia were identified. These belonged to the CAS and EAI clades, respectively, as confirmed upon secondary typing using mycobacterial interspersed repetitive units (MIRUs). The results obtained underline the predominance of historic clones of principal genetic group 1, which are responsible for roughly 45% of all tuberculosis cases in Saudi Arabia. The high rate of clustering observed might be an indication of rapid ongoing transmission within certain communities and/or subpopulations in Saudi Arabia; nonetheless, spoligotyping is known to overestimate clustering, and only a systematic second-line typing, such as MIRUs, coupled with a better tuberculosis registry and epidemiological investigations would allow us to know the exact rate of ongoing transmission and associated risk factors in Saudi Arabia.
PMCID: PMC1951255  PMID: 17507515
20.  Chromosomal instability in in vitro cultured mouse hematopoietic cells associated with oxidative stress 
Hematopoietic stem cells (HSCs) that give rise to all blood cell types are important vehicles for cell-based and gene therapies. After isolation from the bone marrow, HSCs are often cultured in laboratory settings for purposes of ex vivo expansion, gene transduction, and bone marrow transplantation for the treatment of various disorders of the blood and immune systems. Here we demonstrate that during in vitro culturing outside of hypoxic bone marrow niches, HSCs may genetically alter even after short durations of time. Lineage- Scal-1+ c-Kit+ (LSK) cells that are enriched with HSCs revealed significant levels of genomic instability following culture, as evidenced by the emergence of aneuploid cells. To further determine the effects of in vitro culturing conditions, whole bone marrow cells were cultured in a hypoxic environment of 3% oxygen, mimicking conditions within the body's bone marrow, following which, cells proved to undergo less genetic alterations. Proper dosages of the antioxidant N-Acetyl-Cysteine (NAC) similarly decreased occurrences of chromosomal change. Furthermore, analysis of aged hematopoietic cells revealed enhanced in vitro normoxic culture-induced chromosomal instability compared to that of young hematopoietic cells due to noted increased oxidative stress in aged cells. These results reveal that in vitro cell culturing does indeed cause genomic instability in hematopoietic cells. Reduced oxygen to physiological levels and additions of antioxidants can be employed as possible strategies to lower oxidative stress and decrease chances of chromosomal transformation. Because hematopoietic cells are commonly processed in laboratory settings before transplantation for patient treatment, our findings also raise a concern on the therapeutic use of cultured hematopoietic cells.
PMCID: PMC3301439  PMID: 22432090
Hematopoietic cells; stem cells; oxidative stress; chromosomal instability
21.  Ancient Ancestry of KFDV and AHFV Revealed by Complete Genome Analyses of Viruses Isolated from Ticks and Mammalian Hosts 
Alkhurma hemorrhagic fever virus (AHFV) and Kyasanur forest disease virus (KFDV) cause significant human disease and mortality in Saudi Arabia and India, respectively. Despite their distinct geographic ranges, AHFV and KFDV share a remarkably high sequence identity. Given its emergence decades after KFDV, AHFV has since been considered a variant of KFDV and thought to have arisen from an introduction of KFDV to Saudi Arabia from India. To gain a better understanding of the evolutionary history of AHFV and KFDV, we analyzed the full length genomes of 16 AHFV and 3 KFDV isolates.
Methodology/Principal Findings
Viral genomes were sequenced and compared to two AHFV sequences available in GenBank. Sequence analyses revealed higher genetic diversity within AHFVs isolated from ticks than human AHFV isolates. A Bayesian coalescent phylogenetic analysis demonstrated an ancient divergence of AHFV and KFDV of approximately 700 years ago.
The high sequence diversity within tick populations and the presence of competent tick vectors in the surrounding regions, coupled with the recent identification of AHFV in Egypt, indicate possible viral range expansion or a larger geographic range than previously thought. The divergence of AHFV from KFDV nearly 700 years ago suggests other AHFV/KFDV-like viruses might exist in the regions between Saudi Arabia and India. Given the human morbidity and mortality associated with these viruses, these results emphasize the importance of more focused study of these significant public health threats.
Author Summary
Alkhurma hemorrhagic fever (AHF) and Kyasanur Forest disease (KFD) viruses both cause serious and sometimes fatal human disease in their respective ranges, Saudi Arabia and India. AHFV was first identified in the mid-1990s and due to its strong genetic similarity to KFDV it has since been considered the result of a recent introduction of KFDV into Saudi Arabia. To gain a better understanding of the evolutionary history of AHFV and KFDV, we sequenced the full-length genomes of 3 KFDV and 16 AHFV. Sequence analyses show a greater genetic diversity within AHFV than previously thought, particularly within the tick population. The phylogeny constructed with these 19 full-length sequences and two AHFV sequences from GenBank indicates AHFV diverged from KFDV almost 700 years ago. Given the presence of competent tick vectors in the regions between and surrounding Saudi Arabia and India and the recent identification of AHFV in Egypt, these results suggest a broader geographic range of AHFV and KFDV, and raise the possibility of other AHFV/KFDV–like viruses circulating in these regions.
PMCID: PMC3186760  PMID: 21991403
22.  Detection of FLT3 Oncogene Mutations in Acute Myeloid Leukemia Using Conformation Sensitive Gel Electrophoresis 
FLT3 (fms-related tyrosine kinase 3) is a receptor tyrosine kinase class III that is expressed on by early hematopoietic progenitor cells and plays an important role in hematopoietic stem cell proliferation, differentiation and survival. FLT3 is also expressed on leukemia blasts in most cases of acute myeloid leukemia (AML). In order to determine the frequency of FLT3 oncogene mutations, we analyzed genomic DNA of adult de novo acute myeloid leukemia (AML). Polymerase chain reaction (PCR) and conformation-sensitive gel electrophoresis (CSGE) were used for FLT3 exons 11, 14, and 15, followed by direct DNA sequencing. Two different types of functionally important FLT 3 mutations have been identified. Those mutations were unique to patients with inv(16), t(15:17) or t(8;21) and comprised fifteen cases with internal tandem duplication (ITD) mutation in the juxtamembrane domain and eleven cases with point mutation (exon 20, Asp835Tyr). The high frequency of the flt3 proto-oncogene mutations in acute myeloid leukemia AML suggests a key role for the receptor function. The association of FLT3 mutations with chromosomal abnormalities invites speculation as to the link between these two changes in the pathogenesis of acute myeloid leukemiaAML. Furthermore, CSGE method has shown to be a rapid and sensitive screening method for detection of nucleotide alteration in FLT3 gene. Finally, this study reports, for the first time in Saudi Arabia, mutations in the human FLT3 gene in acute myeloid leukemia AML patients.
PMCID: PMC2635624  PMID: 19330068
AML; Flt3; ITD; CSGE; Mutational analysis
23.  The Dermatology workforce in Saudi Arabia: Current trends, challenges and future directions 
To provide a snapshot of the dermatology work force in Saudi Arabia.
We collected data on the supply and distribution of dermatologists in Saudi Arabia. We discussed the current status of dermatology manpower issues in Saudi Arabia.
We found that between 1987 and 2007, the availability of dermatologists to population in Saudi Arabia rose by 60 %, from 2.35 to 3.76 dermatologists per 100,000 Saudi Arabian individuals. However, the current workforce is already out of balance in several ways. We have an excess of non-Saudi citizen dermatologists and a barely adequate supply of Saudi dermatologists. The dermatologist population is unbalanced with regard to gender and uneven in terms of geographic distribution.
The dermatology workforce does not match well with the nation’s health care goals. We should create a more successful and stable match between the talent supply and health care system requirements.
PMCID: PMC3068825  PMID: 21475556
Dermatology; Manpower; Saudi Arabia
24.  Hematopoietic Stem Cell Transplantation in Thalassemia and Sickle Cell Anemia 
The globally widespread single-gene disorders β-thalassemia and sickle cell anemia (SCA) can only be cured by allogeneic hematopoietic stem cell transplantation (HSCT). HSCT treatment of thalassemia has substantially improved over the last two decades, with advancements in preventive strategies, control of transplant-related complications, and preparative regimens. A risk class–based transplantation approach results in disease-free survival probabilities of 90%, 84%, and 78% for class 1, 2, and 3 thalassemia patients, respectively. Because of disease advancement, adult thalassemia patients have a higher risk for transplant-related toxicity and a 65% cure rate. Patients without matched donors could benefit from haploidentical mother-to-child transplantation. There is a high cure rate for children with SCA who receive HSCT following myeloablative conditioning protocols. Novel non-myeloablative transplantation protocols could make HSCT available to adult SCA patients who were previously excluded from allogeneic stem cell transplantation.
The genetic diseases thalassemia and sickle cell anemia are curable by allogeneic hematopoietic stem cell transplantation. The distinct pathogeneses of the disorders necessitate differences in the procedures used.
PMCID: PMC3331690  PMID: 22553502
25.  Development of a health-related website for parents of children receiving hematopoietic stem cell transplant: HSCT-CHESS 
Parents of pediatric hematopoietic stem cell transplant (HSCT) play a pivotal role in the care of their child during and after transplant. In addition to the child’s comforter, parents also serve as care coordinators and conduits of communication between various health care providers, family and community members. The stress on the parent and family is enormous during this process, which for many is compounded by geographic dislocation to accompany their child during the rigorous treatment and recovery process. For many parents, their own recovery spans months to years.
Parental activation, a process of becoming informed to participate in decisions, collaborate with health care providers, and manage care provided the conceptual framework to develop an eHealth approach for this population. HSCT-CHESS was developed, based on previous success with an existing eHealth system of integrated services, the Comprehensive Health Enhancement Support System (CHESS™). CHESS™ is designed to help individuals and families cope with a health crisis or medical concern. The iterative user-centered development process for HSCT-CHESS included parents of HSCT recipients, representatives from an HSCT Advocacy Group, and members of the clinical, research, development and design teams. This rigorous process, including online focus groups and surveys, utilization of a parental user group, and an editorial and development process are described.
As the population of cancer survivors and caregivers increase and as the oncology workforce becomes more stretched; developing eHealth applications may be an approach to address many of caregivers unmet needs. The purpose in describing this process is to help others when considering such an endeavor. HSCT-CHESS is now being tested in a randomized controlled trial versus standard care to evaluate its impact on the quality of life of both the parent and child HSCT recipient.
PMCID: PMC3049177  PMID: 19967409
Internet; Patient education; Caregivers; Parents; Information services; Self-efficacy

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