Natural Killer (NK) cells are the third population of lymphocyte in the mononuclear cell compartment that triggers first-line of defense against viral infection and tumor transformation. Historically, NK cells were thought of as components of innate immunity based on their intrinsic ability to spontaneously kill target cells independent of HLA antigen restriction. However, it is now clear that NK cells are quite sophisticated and use a highly specific and complex target cell recognition receptor system arbitrated via a multitude of inhibitory and activating receptors. Killer cell immunoglobulin-like receptors (KIR) are the key receptors of human NK cells development and function. To date, fourteen distinct KIRs have been identified: eight are inhibitory types, and six are activating types. The number and type of KIR genes present varies substantially between individuals. Inhibitory KIRs recognize distinct motifs of polymorphic HLA class I molecules. Upon engagement of their specific HLA class I ligands, inhibitory KIR dampen NK cell reactivity. In contrast, activating KIRs are believed to stimulate NK cell reactivity when they sense their ligands (unknown). KIR and HLA gene families map to different human chromosomes (19 and 6, respectively), and their independent segregation produces a wide diversity in the number and type of inherited KIR-HLA combinations, likely contributing to overall immune competency. Consistent with this hypothesis, certain combinations of KIR-HLA variants have been correlated with susceptibility to diseases as diverse as autoimmunity, viral infections, and cancer. This review summarizes our emerging understanding of KIR-HLA diversity in human health and disease.
NK cells; Innate immunity; HLA; KIR; Polymorphism; Immune genes
Multiple myeloma is a malignancy of B-cells that is characterized by the clonal expansion and accumulation of malignant plasma cells in the bone marrow. This disease remains incurable, and a median survival of 3-5 years has been reported with the use of current treatments. Viral-based therapies offer promising alternatives or possible integration with current therapeutic regimens. Among several gene therapy vectors and oncolytic agents, adenovirus has emerged as a promising agent, and it is already being used for the treatment of solid tumors in humans. The main concern with the clinical use of this vector has been its high immunogenicity; adenovirus is often able to induce a strong immune response in the host. Furthermore, new limitations in the efficacy of this therapy, intrinsic to the nature of tumor cells, have been recently observed. For example, our group showed a strong antiviral phenotype in vitro and in vivo in a subset of tumors, shedding new insights that may explain the partial failure of clinical trials based on this promising new therapy. In this review, we describe novel therapeutic approaches that implement viral-based treatments in hematological malignancies and address the novelty as well as the possible limitations of these new therapies, especially in the context of the use of adenoviral vectors for treating multiple myeloma.
Adenovirus; Oncolytic therapy; Multiple myeloma; Antiviral phenotype
Reports of indeterminate lupus anticoagulant (LAC) results are common; however, no published data on their prevalence or clinical significance are available. We investigated the prevalence and clinical characteristics of patients with indeterminate LAC.
We retrospectively reviewed the clinical and serologic characteristics of 256 unselected patients with LAC results.
Indeterminate results were observed in 32.7% of LAC profiles that were least frequent (25.4%) when activated partial thromboplastin time (aPTT) was normal, most frequent (39.8%) when aPTT was elevated, and were observed in 35% of patients taking warfarin. The final indeterminate LAC cohort included 65 patients with a mean follow-up of 18 months. Malignancy and autoimmune disease were present in 29% and 25% of patients, respectively. The most common thrombotic events were deep vein thrombosis (DVT) (28%), cerebral ischemic stroke (14%) and pulmonary embolism (14%). Patients with indeterminate results were more likely to be men, older, and with a history of DVT, superficial thrombosis, or myocardial infarction than patients with negative tests (N=106). Concurrent warfarin therapy was more prevalent in the indeterminate group, but was not statistically significant. In the multivariate analysis, none of the variables showed statistical significance. During follow-up, 10 of 16 patients with indeterminate results showed change in classification upon retesting.
Patients with indeterminate LAC results were common, and their clinical characteristics differed from those with negative results. There is a need for a prospective study of the clinical history of patients with indeterminate LAC results.
Antiphospholipid antibodies; Antiphospholipid syndrome; Indeterminate lupus anticoagulant
Antagonists of CXC chemokine receptor 4 (CXCR4), including AMD3100, induce peripheral mobilization of hematopoietic stem cells and have been approved for clinical use. We explored whether the CXCR4 antagonists affected the survival and proliferation of myeloid leukemia cells in vitro.
The effects of CXCR4 antagonists AMD3100 and T140 on the survival and proliferation of myeloid leukemia cell lines (U937, HL-60, MO7e, KG1a, and K562) as well as CD34+ cells obtained from patients with AML and CML were analyzed by flow cytometry by using annexin V and a colorimetric cell proliferation assay.
AMD3100, but not T140, stimulated the proliferation of leukemia cells in vitro in a dose-dependent manner for up to 5 days (~2-fold increase at a concentration of 10-5 M), which was not abrogated by pretreatment of the cells with pertussis toxin, but was attenuated by RNAi knockdown of CXCR7 transcripts. In contrast, AMD3100 induced a marked decrease in the cell numbers after 5-7 days. AMD3100, but not T140, induced phosphorylation of MAPK p44/p42. AMD3100 increased the number and size of leukemia cell colonies and reduced cell apoptosis during the first 5-7 days of incubation, but the phenomena were reversed during the later period of incubation.
The effects of CXCR4 antagonists on the proliferation of myeloid leukemia cells are not uniform. AMD3100, but not T140, exerts dual effects, initially enhancing and subsequently inhibiting the survival and proliferation of the cells in vitro.
AMD3100; CXCR4; SDF-1; Myeloid leukemia; Cell proliferation; Apoptosis
The aim of this study is to investigate the hematological manifestations of human immunodeficiency virus (HIV) infection, the risk factors for cytopenia, and the effect of highly active anti-retroviral therapy (HAART) on cytopenia.
Medical records of patients treated for HIV at the Seoul National University Hospital from January 2005 to March 2010 were retrospectively reviewed. To determine the impact of HIV itself, we excluded HIV patients who had other conditions that could have resulted in hematological manifestations. Multiple logistic regression analyses were performed to identify risk factors for cytopenia.
A total of 621 cases were investigated, and after exclusion, data of 472 patients were analyzed. The frequency of cytopenia was anemia, 3.0% (14/472); neutropenia, 10.0% (47/472); thrombocytopenia, 2.4% (12/472); lymphopenia, 25.7% (121/470); isolated cytopenia, 11.2% (53/472); and bicytopenia, 2.1% (10/472). The leading risk factor for cytopenia identified by multivariate logistic regression methods was AIDS status at initial presentation. After HAART, cytopenia was reversed in the majority of patients (thrombocytopenia, 100%; neutropenia, 91.1%; and anemia, 84.6%).
This study isolated the impact of HIV infection alone on hematologic manifestations and confirmed that these changes were reversible by HAART. Control of the HIV infection will have the main role in the management of hematological manifestations of the virus.
HAART; Hematologic manifestations; HIV infection; Risk factor
The effects of chimerism on outcomes following allogeneic hematopoietic stem cell transplantation (HSCT) are unclear and may differ between diseases. We retrospectively evaluated the association between chimerism and transplant outcomes in children with nonmalignant diseases.
Chimerism was evaluated using short-tandem repeat polymerase chain reaction (STR-PCR) in 48 patients, with mixed chimerism (MC) defined as greater than 1% recipient cells.
The only variable exerting a significant influence on patients' chimerism status was the number of infused CD34+ cells. MC was detected in 23 transplants (9 showing transient MC; 10 with sustained low levels [≤30%] of autologous cells; and 4 with high-level MC [>30%]). The degree of STR-PCR at 28 days after HSCT was significantly higher in patients with high-level MC than those with transient or low-level MC. All patients with transient or low-level MC successfully maintained engraftment and showed a clinical response to HSCT, whereas 2 of the 4 patients with high-level MC experienced graft failure. The incidences of grades II-IV acute and chronic graft-versus-host disease (GVHD) were significantly higher in patients with complete donor chimerism (CC) than MC. We observed no significant survival differences between CC and MC groups. However, the survival rate was lower in patients with high MC than those with low-level or transient MC (P=0.03).
In non-malignant diseases, MC may indicate a tolerant state with a decreased incidence of GVHD. However, high-level MC may signify an increased risk of graft failure and a lower survival rate.
Non-malignant disease; Allogeneic hematopoietic stem cell transplantation; Chimerism
The underlying rationale of platelet rich plasma (PRP) therapy is that an injection of concentrated PRP at the site of injury may promote tissue repair via cytokine release from platelets. The molecular mechanisms of PRP therapy in the skin wound healing process are not well understood at present, and would benefit from clarification.
PRP was stimulated with angonists for 5 min, and cytokine profile analysis was performed. To investigate the wound healing activity of PRP, cell proliferation and migration analyses were performed in skin cells. The effects of PRP were analyzed on the expression and activity of matrix metalloproteinase (MMP)-1, -2, -9, and the activation of transcription factors.
Thrombin was found to be a strong stimulator of PRP activation to release growth factors and chemokines. PRP induced cell proliferation and migration in HUVECs, HaCaT cells, and HDFs, as well as MMP-1and MMP-9 expression in HaCaT cells, but PRP did not have a significant effect on the expression or activity of MMPs in HDFs. The transcription factors, including signal transducer and activator of transcription-3 (STAT-3) were found to be phosphorylated following PRP treatment in HaCaT cells.
In this study, we have identified the cytokine profile of activated PRP after agonist stimulation. We have shown that PRP plays an active role in promoting the proliferation and migration of skin cells via the regulation of MMPs, and this may be applicable to the future development of PRP therapeutics to enhance skin wound healing.
Platelet rich plasma (PRP); Wound healing; Cytokine profile; Cell proliferation; Cell migration; Matrix metalloproteinase
Splenic infarction is most commonly caused by cardiovascular thromboembolism; however, splenic infarction can also occur in hematologic diseases, including sickle cell disease, hereditary spherocytosis, chronic myeloproliferative disease, leukemia, and lymphoma. Although 10% of splenic infarction is caused by hematologic diseases, it seldom accompanies autoimmune hemolytic anemia (AIHA). We report a case of a 47-year-old woman with iron deficiency anemia who presented with pain in the left upper abdominal quadrant, and was diagnosed with AIHA and splenic infarction. Protein C activity and antigen decreased to 44.0% (60-140%) and 42.0% (65-140%), respectively. Laboratory testing confirmed no clinical cause for protein C deficiency, such as disseminated intravascular coagulation, sepsis, hepatic dysfunction, or acute respiratory distress syndrome. Protein C deficiency with splenic infarction has been reported in patients with viral infection, hereditary spherocytosis, and leukemia. This is a rare case of splenic infarction and transient protein C deficiency in a patient with AIHA.
Autoimmune hemolytic anemia; Protein C deficiency; Splenic infarction
We report a case of a 51-year-old woman with Evans syndrome (autoimmune hemolytic anemia and primary immune thrombocytopenia) and hypothyroidism. She was previously diagnosed with Hashimoto's thyroiditis in 1994 (age, 35) and autoimmune hemolytic anemia (AIHA) 3 years ago. She was treated with oral prednisolone. After a period, in which the anemia waxed and waned, there was an abrupt development of thrombocytopenia (nadir 15×109/L) that coincided with the tapering off of prednisolone after 3 years of administration. Because her thrombocytopenia was refractory to prednisolone, we administered rituximab (375 mg/m2 weekly) for 4 weeks. Two weeks after the completion of the rituximab treatment, her platelet count was up to 92×109/L. No intermittent peaking of thyroid stimulating hormone occurred after rituximab treatment was initiated. Evans syndrome and autoimmune thyroiditis might share common pathophysiological mechanisms. This notion supports the use of rituximab in a patient suffering from these disorders.
Evans syndrome; ITP; AIHA; Autoimmune thyroiditis
Precursor B-cell lymphoblastic lymphoma (B-LBL) is an uncommon high-grade neoplasm of immature B cells. It occurs predominantly in childhood with extranodal involvement such as skin and bone. Therefore, primary cutaneous involvement in elderly adults is a very rare manifestation of B-LBL. Here, we report a 78-year-old man with B-LBL presenting as a single cutaneous lesion which was immunohistochemically positive for leukocyte common antigen (LCA), CD79a, paired box 5 (PAX5), B cell lymphoma-2 (bcl-2), and terminal deoxynucleotidyl transferase (TdT) staining, but was without systemic involvement. The patient was treated using cyclophosphamide, adriamycin, vincristine, and prednisolone (CHOP), and achieved complete response (CR) at the first response assessment conducted after 3 CHOP cycles. After an additional cycle of CHOP treatment, radiotherapy was administered at a total dose of 3,600 cGy over 4 weeks. At the 21-month follow-up, he had maintained CR.
Precursor B-cell lymphoblastic leukemia-lymphoma; Cutaneous; Adult; CHOP; Radiotherapy
Chronic GVHD was recognized as a complication of allogeneic hematopoietic cell transplantation more than 30 years ago, but progress has been slowed by the limited insight into the pathogenesis of the disease and the mechanisms that lead to development of immunological tolerance. Only 6 randomized phase III treatment studies have been reported. Results of retrospective studies and prospective phase II clinical trials suggested overall benefit from treatment with mycophenolate mofetil or thalidomide, but these results were not substantiated by phase III studies of initial systemic treatment for chronic GVHD. A comprehensive review of published reports showed numerous deficiencies in studies of secondary treatment for chronic GVHD. Fewer than 10% of reports documented an effort to minimize patient selection bias, used a consistent treatment regimen, or tested a formal statistical hypothesis that was based on a contemporaneous or historical benchmark. In order to enable valid comparison of the results from different studies, eligibility criteria, definitions of individual organ and overall response, and time of assessment should be standardized. Improved treatments are more likely to emerge if reviewers and journal editors hold authors to higher standards in evaluating manuscripts for publication.
Chronic graft-versus-host disease; Treatment; Phase II clinical trials; Review
On April 23, 1951, a 30-year-old woman received the first intentional ABOi (ABO incompatible) renal transplantation in Boston. At that time, it was commonly believed that intensely rinsing the graft to remove blood would be sufficient to overcome any immunological problems associated with blood type incompatibility. However, when the abovementioned patient and another ABOi transplant recipient died within a month, Humes and colleagues arrived at the same conclusion: "We do not feel that renal transplantation in the presence of blood incompatibility is wise." In the decades that followed, we learned that the oligosaccharide surface antigens representing the ABO-blood group antigens are expressed not only on erythrocytes but also on cells from various tissues, including the vascular endothelium. The growing gap between organ demand and availability has sparked efforts to overcome the ABO barrier. After its disappointing results in the early 1970s, Japan became the leader of this endeavor in the 1980s. All protocols are based on 2 strategies: removal of preformed antibodies with extracorporeal techniques and inhibition of ongoing antibody production. Successful ABOi renal transplantation became possible with the advent of splenectomy, new immunosuppressive drugs (e.g., rituximab, a monoclonal antibody against CD20), and extracorporeal methods such as antigen-specific immunoadsorption. This review summarizes the underlying pathophysiology of ABOi transplantation and the different protocols available. Further, we briefly touch potential short- and long-term problems, particularly the incidence of infectious complications and malignancies, that can arise with high-intensity immunosuppressive therapy.
Graft survival; Graft loss; Rejection; Preconditioning
Through the phase 3 International Randomized Study of Interferon vs. STI571 (IRIS) trial, imatinib emerged as the standard treatment for chronic myeloid leukemia (CML) and has successfully prolonged the duration of both the chronic phase (CP) and the disease-free state. The majority of newly diagnosed patients treated for CP-CML achieve a complete cytogenetic response (CCyR), and over time, most of these eventually achieve major molecular responses (MMRs) and even complete molecular responses (CMRs). In ongoing phase 3 randomized trials of second-generation tyrosine kinase inhibitors (TKIs), nilotinib and dasatinib have been found to have superior efficacies in helping achieve cytogenetic and molecular responses, including MMRs and CMRs. However, only the MMR rate was significantly higher in bosutinib compared with the imatinib control, but not in CCyR rate. Current reports of imatinib discontinuation suggested that achieving CMR is an important prerequisite for CML to be cured. Recent data from the STIM (Stop Imatinib) trial showed that imatinib can be successfully discontinued in patients who achieve a certain level of CMR. Standardized real-time quantitative reverse transcriptase-polymerase chain reaction (RQ-PCR) assays have been available in routine clinical practice, and efforts are being focused on achieving higher sensitivity and optimizing the time of imatinib discontinuation. Although very few patients are cured by administration of only Bcr-Abl TKIs, including imatinib and second-generation TKIs, current advances may eventually make this possible. This report summarizes the detailed clinical data obtained in the DASISION, ENESTnd, and BELA studies and discusses high-sensitivity detection methods and future therapeutic strategies.
CML; Imatinib; Nilotinib; Dasatinib; PCR; Leukemia stem cell
BAFF (B cell-activating factor) and APRIL (a proliferation-inducing ligand) are members of the tumor necrosis factor family and promote B cell survival and proliferation. We evaluated the correlation between serum concentration of BAFF or APRIL and severity of acute graft-versus-host disease (GVHD).
Fifteen patients who received allogeneic hematopoietic stem transplantation for leukemia and developed acute GVHD were enrolled. We determined serum concentrations of BAFF and APRIL at the onset of the first clinical manifestation of GVHD by enzyme-linked immunosorbent assay.
Nine patients had grade 2 acute GVHD, and 6 had grade 3-4 acute GVHD. The BAFF serum concentration was higher in patients with grade 3-4 acute GVHD (1,093.42 in grade 2 vs. 2,171.99 pg/mL in grade 3-4), although the difference was not significant (P=0.077). However, the ratio of BAFF serum concentration to absolute lymphocyte count (ALC) (BAFF/ALC) was significantly higher in patients with grade 3-4 acute GVHD (P=0.045). The APRIL serum concentration and APRIL/ALC ratio showed similar results (P=0.077 and P=0.013, respectively).
Patients with grade 3-4 acute GVHD had higher BAFF/ALC and APRIL/ALC ratios than patients with grade 2 acute GVHD. These findings suggest that B cells might play an important role in the development of acute GVHD, and that the BAFF and APRIL concentrations in serum might be significant predictive factors for estimating the severity of acute GVHD. Their clinical significance should be further evaluated in a larger patient population.
B cell-activating factor (BAFF); A proliferation-inducing ligand (APRIL); Acute graft-versus-host disease; Allogeneic hematopoietic stem cell transplantation
The clinical efficacy and safety of fludarabine combination chemotherapy was investigated for the treatment of previously untreated patients with low-grade (NHL).
Twenty-five patients who were newly diagnosed as low-grade NHL were treated with fludarabine combination chemotherapy. Fludarabine combination regimens consisted of fludarabine, mitoxantrone and dexamethasone or fludarabine, cyclophosphamide and mitoxantrone with or without rituximab and repeated every 4 weeks.
The median age was 60 years (range, 35-77 years), with 13 of 25 patients (52%) ≥60 years of age. Seven of 25 patients (28%) with an intermediate risk follicular lymphoma international prognostic index (FLIPI) and 9 of 25 patients (36%) with a high risk FLIPI were enrolled in this study. The delivered median number of chemotherapy was six (range, 2-9 cycles). The overall response rate with fludarabine-based treatment was 88%, including 52% complete remission and 36% partial remission. During the median follow-up of 19 months, the estimated 2-year event-free survival was 63±10% (95% CI, 43-83) and the 2-year overall survival was 78±9% (95% CI, 60-96). Fludarabine combination chemotherapy was frequently associated with grade 3 or 4 neutropenia in 84% patients. However, neutropenic infection was observed in only one (4%) patient. Four patients (16%) showed grade 3 or more non-hematologic toxicities, such as acute coronary syndrome, intracranial hemorrhage, anaphylaxis and gastric cancer.
Fludarabine-combination treatment was a highly active regimen with well toleration in untreated low-grade NHL.
Fludarabine; Primary; Lymphoma
The clinical presentation and course of Langerhans cell histiocytosis (LCH) are variable, ranging from an isolated, spontaneously remitting bone lesion to multisystem disease with risk organ involvement. Treatment of LCH ranges from a wait-and-see attitude to intensive multidrug therapy and, in some cases, bone marrow transplantation. It is necessary to develop an objective score for assessing disease activity in patients with LCH. We propose a new clinical scoring system to evaluate disease activity at diagnosis that can predict the clinical outcomes of LCH and correlate it with clinical courses.
Clinical data, obtained from children diagnosed with LCH at Asan Medical Center and Hanyang University Hospital between March 1998 and February 2009, were studied retrospectively. The scoring system was developed according to the basic biological data, radiological findings, and physical findings and applied to a database containing information on 133 patients.
The median age of the 133 patients (74 male, 59 female) was 52 months (range, 0.6-178 months), and LCH was diagnosed based on CD1a positivity. At diagnosis, the score distributions were highly asymmetrical: the score was between 1 and 2 in 75.9% of cases, 3-6 in 15.8%, and greater than 6 in 8.3%. Initial scores above 6 were highly predictive of reactivation and late complications.
This new LCH disease activity score provides an objective tool for assessing disease severity, both at diagnosis and during follow-up.
Histiocytosis; Langerhans cells; Disease activity; Clinical score