High-dose chemotherapy with peripheral blood stem cell (PBSC) transplantation in advanced germ cell tumour (GCT) patients is widely applied. The aims of this study were: (1) To examine the presence of alphafetoprotein (AFP) bearing tumour cells in PBSC harvests from advanced GCT patients obtained after multiple cycles of induction chemotherapy. (2) To determine whether induction chemotherapy contributed to in vivo purging of the tumour. We evaluated cryopreserved PBSC samples from 5 patients with advanced stage II/III AFP producing GCT. PBSC were separated after the first, second and third cycles of induction chemotherapy. Those samples were analysed using the nested reverse transcription polymerase chain reaction (RT-PCR) method to detect AFP mRNA. Although, in all patients, AFP mRNA was detected in PBSC samples after the first or second cycle of induction chemotherapy, but was not detected in 3 of 4 samples after the third cycle of chemotherapy. Although it is not clear whether tumour cells contaminating PBSC fraction contribute to disease relapse, PBSC harvested after at least 3 cycles of induction chemotherapy might be recommended to avoid such a possibility. © 2001 Cancer Research Campaignhttp://www.bjcancer.com
germ cell tumour; alphafetoprotein; peripheral blood stem cells; reverse transcription polymerase chain reaction
By 2003, 97% autologous transplants and 65% of allogeneic transplants in Europe used mobilised peripheral blood stem cells (PBSC). Soon after their introduction in the early 1990's, PBSC were associated with faster haemopoietic recovery, fewer transfusions and antibiotic usage, and a shorter hospital stay. Furthermore, ease and convenience of PBSC collection made them more appealing than BM harvests. Improved survival has hitherto been demonstrated in patients with high risk AML and CML. However, the advantages of PBSC come at a price of a higher incidence of extensive chronic GVHD. In order to be present in the blood, stem cells undergo the process of “mobilisation” from their bone marrow habitat. Mobilisation, and its reciprocal process – homing – are regulated by a complex network of molecules on the surface of stem cells and stromal cells, and enzymes and cytokines released from granulocytes and osteoclasts. Knowledge of these mechanisms is beginning to be exploited for clinical purposes. In current practice, stem cell are mobilised by use of chemotherapy in conjunction with haemopoietic growth factors (HGF), or with HGF alone. Granulocyte colony stimulating factor has emerged as the single most important mobilising agent, due to its efficacy and a relative paucity of serious side effects. Over a decade of use in healthy donors has resulted in vast experience of optimal dosing and administration, and safety matters. PBSC harvesting can be performed on a variety of cell separators. Apheresis procedures are nowadays routine, but it is important to be well versed in the possible complications in order to avoid harm to the patient or donor. To ensure efficient collection, harvesting must begin when sufficient stem cells have been mobilised. A rapid, reliable, standardized blood test is essential to decide when to begin harvesting; currently, blood CD34+ cell counting by flow cytometry fulfils these criteria. Blood CD34+ cell counts strongly correlate with the apheresis yields. These are, in turn, predictive of the speed of haemopoietic recovery after transplantation, which has helped establish the adequate cell dose for transplantation. Following collection, PBSC may be transfused unmanipulated, processed to select specific cell subtypes, or stored for future use. Cryopreservation techniques allow long term storage of stem cells without significant loss of viability. Increasingly demanding calls for safety led to introduction of vapour phase storage, separate storage of infected material, and mandatory quality control measures at all stages of the cryopreservation process and subsequent thawing and transfusion. At the same time, safety of the personnel working in stem cell processing and storage laboratories is safeguarded by a set of regulations devised to minimize the risk of infection, injury or hypoxia. Requirements for quality and safety have been shaped into a number of documents and directives in Europe and USA, emphasising the importance of product traceability, reporting of adverse reactions, quality management systems (standard operating procedures, guidelines, training records, reporting mechanisms and records), requirements for cell reception, quarantine, process control, validation and storage. Establishments that collect, process and store stem cells must be accredited or licensed by appropriate national or international authorities on a regular basis. These regulatory measures have recently become law across the European Union.
Autologous transplant; allogeneic transplant; peripheral blood stem cells; haemopoietic growth factor
Peripheral blood stem cells (PBSC) were used to augment autologous bone marrow transplantation (ABMT), aiming to hasten engraftment after high dose treatment in a group of heavily pretreated patients. PBSC were obtained by leukapheresis during the rebound after standard chemotherapy. In 11 patients aged 7-17 years, high dose chemotherapy consisted of busulphan 16 mg/kg orally with melphalan 160 mg/m2 intravenously for seven patients, and melphalan 200 mg/m2 intravenously alone for four. The median number of granulocyte-macrophage colony forming units in the reinfused PBSC was 3.42 x 10(4)/kg (3.03-18.01) and bone marrow 12.4 x 10(4)/kg (4.16-28.6). Neutrophil recovery to > or = 0.5 x 10(9)/l and platelet transfusion independence occurred at a median of 14 days (11-18) and 22 days (9-84) respectively. In five patients the early engraftment was transient with neutrophils again dropping below 0.5 x 10(9)/l then slowly recovering. There was one toxic death due to sepsis. PBSC harvesting in these children was undertaken without interrupting routine chemotherapy and without the use of bone marrow growth factors. In some patients PBSC failed to influence engraftment and the use of combined chemotherapy and growth factor priming for PBSC collection may give improved results.
The aim of this study was to evaluate the feasibility of a high-dose intensity and high-dose density multicycle epirubicin and cyclophosphamide regimen with peripheral blood stem cells (PBSC) and haematopoietic growth factor (G-CSF) support in advanced breast cancer patients. From August 1994 to September 1999, 56 breast cancer patients (8 stage IIIB and 48 stage IV) received 205 courses of cyclophosphamide 3 g m−2and epirubicin 100 mg m−2every 14 days. G-CSF 5 μg kg−1day−1was administered from day 3 to neutrophil recovery. 4 courses were planned. PBSC were collected after course 1, and reinfused after courses 3 and 4, with ≥ 2 × 106CD34+ PBSC kg−1required for each reinfusion. 48 patients (86%) received all 4 planned courses. Early withdrawal was consecutive to infectious complications (n= 4), severe asthenia (n= 3), haemorrhagic cystitis (n= 1). A median number of 10.8 × 106CD34+ PBSC kg−1(range, 3–80) was harvested with 1 or 2 apheresis in 48 patients (94%). Median relative dose intensity was 91.3% (range, 72–102%). Grade 4 neutrophil toxicity was observed in 100% of patients. Febrile neutropenia was observed in 40% of courses (median duration 2 days). Red blood cells and platelets had to be transfused in 54% and 27% of courses, respectively. There were no toxic deaths. Objective response rate was 69% in stage IV patients (31/45 evaluable pts), with a 16% complete response rate. Their median progression-free and overall survivals were 22.5 and 37 months, respectively. This epirubicine-containing high-dose regimen appeared feasible, albeit with high toxicity. Time-related progression parameters exceed commonly reported ones. Controlled studies of upfront sequential high-dose chemotherapy are still needed to evaluate its real benefit. © 2001 Cancer Research Campaign
breast cancer; advanced; chemotherapy; high-dose
Double high-dose chemotherapy (HDCT) was applied to 18 patients with highrisk neuroblastoma including 14 patients who could not achieve complete response (CR) even after the first HDCT. In 12 patients, successive double HDCT was rescued with peripheral blood stem cells collected during a single round of leukaphereses and in 6 patients, second or more rounds of leukaphereses were necessary after the first HDCT to rescue the second HDCT. The median interval between the first and second HDCT (76 days; range, 47-112) in the single harvest group was shorter than that (274.5 days; range, 83-329) in the double harvest group (p<0.01). Hematologic recovery was slow in the second HDCT. Six (33.3%) treatment-related mortalities (TRM) occurred during the second HDCT but were not related to the shorter interval. Disease-free survival rates at 2 years with a median follow-up of 24 months (range, 6-46) in the single and double harvest group were 57.1% and 33.3%, respectively. These results suggest that successive double HDCT using the single harvest approach may improve the survival of high-risk patients, especially who could not achieve CR after the first HDCT despite delayed hematologic recovery and high rate of TRM during the second HDCT.
Poor peripheral blood stem cell (PBSC) mobilization predicts worse outcome for myeloma and lymphoma patients post autologous stem cell transplant (ASCT). We hypothesize that PBSC harvest using plerixafor and G-CSF in poor mobilizers may improve long-term outcome. We retrospectively analyzed the data on patients who had second PBSC mobilization using plerixafor and G-CSF as a rescue. Nine lymphoma and 8 multiple myeloma (MM) patients received the drug. A control group of 25 MM and lymphoma patients who were good mobilizers with G-CSF only was used for comparison. Sixteen of the 17 poor mobilizers proceeded to ASCT, and one MM patient had tandem transplants. Length of hospital stay, infection incidence, granulocyte engraftment, and long-term hematopoietic recovery were not significantly different between the two groups. In conclusion, all poor mobilizers were able to obtain adequate stem cells transplant dose and had similar transplant course and long-term outcome to that of the control good mobilizers group.
Unmanipulated haploidentical/mismatched related transplantation with combined granulocyte-colony stimulating factor-mobilised peripheral blood stem cells (G-PBSCs) and granulocyte-colony stimulating factor-mobilised bone marrow (G-BM) has been developed as an alternative transplantation strategy for patients with haematologic malignancies. However, little information is available about the factors predicting the outcome of peripheral blood stem cell (PBSC) collection and bone marrow (BM) harvest in this transplantation. The effects of donor characteristics and procedure factors on CD34+ cell yield were investigated. A total of 104 related healthy donors received granulocyte-colony stimulating factor (G-CSF) followed by PBSC collection and BM harvest. Male donors had significantly higher yields compared with female donors. In multiple regression analysis for peripheral blood collection, age and flow rate were negatively correlated with cell yield, whereas body mass index, pre-aphaeresis white blood cell (WBC) and circulating immature cell (CIC) counts were positively correlated with cell yields. For BM harvest, age was negatively correlated with cell yields, whereas pre-BM collection CIC counts were positively correlated with cell yield. All donors achieved the final product of ≥6 ×106 kg−1 recipient body weight. This transplantation strategy has been shown to be a feasible approach with acceptable outcomes in stem cell collection for patients who received HLA-haploidentical/mismatched transplantation with combined G-PBSCs and G-BM. In donors with multiple high-risk characteristics for poor aphaeresis CD34+ cell yield, BM was an alternative source.
granulocyte-colony stimulating factor; HLA-haploidentical/mismatched related donors; leukaemia; mobilisation; transplantation
In order to clarify the optimal timing for peripheral blood stem cell (PBSC) collection, PBSC collection records of 323 children who were scheduled to undergo autologous stem cell transplantation from two study periods differing in the timing of PBSC collection were analyzed. In the early study period (March 1998 to August 2007, n=198), PBSC collection was initiated when the peripheral WBC count exceeded 1,000/µL during recovery from chemotherapy. Findings in this study period indicated that initiation of PBSC collection at a higher WBC count might result in a greater CD34+ cell yield. Therefore, during the late study period (September 2007 to December 2012, n=125), PBSC collection was initiated when the WBC count exceeded 4,000/µL. Results in the late study period validated our conclusion from the early study period. Collection of a higher number of CD34+ cells was associated with a faster hematologic recovery after transplant in the late study period. Initiation of PBSC collection at WBC count > 4,000/µL was an independent factor for a greater CD34+ cell yield. In conclusion, PBSC collection at a higher WBC count is associated with a greater CD34+ cell yield, and consequently a faster hematologic recovery after transplant.
High-Dose Chemotherapy; Autologous Stem Cell Transplantation; Peripheral Blood Stem Cell Collection
To assess the feasibility of adding dose-intensive topotecan and cyclophosphamide to induction therapy for newly diagnosed high-risk neuroblastoma (HRNB).
Patients and Methods
Enrolled patients received two cycles of topotecan (approximately 1.2 mg/m2/d) and cyclophosphamide (400 mg/m2/d) for 5 days followed by four cycles of multiagent chemotherapy (Memorial Sloan-Kettering Cancer Center [MSKCC] regimen). Pharmacokinetically guided topotecan dosing (target systemic exposure with area under the curve of 50 to 70 ng/mL/hr) was performed. Peripheral-blood stem cell (PBSC) harvest and surgical resection of residual primary tumor occurred after cycles 2 and 5, respectively. Patients achieving at least a partial response received myeloablative chemotherapy with PBSC rescue and radiation to the presurgical primary tumor volume. Oral 13-cis-retinoic acid maintenance therapy was administered twice daily for 14 days in six 28-day cycles.
Thirty-one patients were enrolled onto the study. No deaths related to toxicity or dose-limiting toxicities occurred during induction. Mucositis rarely occurred after topotecan cycles (9.7%) in contrast to 30% after MSKCC cycles. Thirty patients underwent PBSC collection with median 31.1 × 106 CD34+ cells/kg (range, 1.8 to 541.8 × 106 CD34+ cells/kg), all negative for tumor contamination by immunocytochemical analysis. Targeted topotecan systemic exposure was achieved in 26 (84%) of 31 patients. At the end of induction, 26 patients (84%) had tumor response and one patient had progressive disease. In the overall cohort, 3-year event-free and overall survival were 37.8% ± 9.4% and 57.1% ± 9.4%, respectively.
This pilot induction regimen was well tolerated with expected and reversible toxicities. These data support investigation of efficacy in a phase III clinical trial for newly diagnosed HRNB.
Mobilized peripheral blood (PB) is widely used as source of stem cells (PBSCs) for autologous stem cell transplantation (ASCT). The use of cytokines, alone or in combination with chemotherapy (chemomobilization), is the most common strategy applied to mobilize and collect PBSCs. However, a significant proportion of cancer patients fail to mobilize enough PBSCs to proceed to ASCT. Plerixafor is a small molecule that reversibly and transiently disrupts the interaction between the chemokine receptor CXCR4 and its ligand CXCL12 (formerly known as stroma derived factor 1, SDF-1) leading to the rapid release of CD34+ hematopoietic stem cells from the bone marrow (BM) to PB. Plerixafor has been recently approved to enhance PBSC mobilization in adult patients with multiple myeloma or non-Hodgkin lymphoma and has been shown to be more effective than G-CSF alone. There is limited experience on combining plerixafor with chemotherapy plus G-CSF in patients who mobilize poorly. Current evidence suggests that the addition of plerixafor is safe and effective in the large majority of the patients with low blood CD34+ cell count after mobilization and/or poor yield after the first collection(s). Circulating CD34+ cells can be increased by several folds with plerixafor and the majority of the patients considered “poor mobilizers” can be successfully collected. Overall, its mechanism of action inducing the rapid release of CD34+ cells from the BM to the circulation makes plerixafor suitable for the ‘preemptive’ use in patients who are hard-to-mobilize.
Peripheral blood stem cells (PBSC) have become the preferred stem cell source for autologous hematopoietic transplantation. A critical aspect of this treatment modality is cryopreservation of the stem cell products, which permits temporal separation of the PBSC mobilization/collection phase from the subsequent high-dose therapy. While controlled rate freezing and liquid nitrogen storage have become “routine” practice in many cell processing facilities, there is clearly room for improvement, as current cryopreservation media formulations still result in significant loss and damage to the stem/progenitor cell populations essential for engraftment, and can also expose the patients to relatively undefined serum components and larger volumes of DMSO that can contribute to the morbidity and mortality of the transplant therapy.
This study compared cryopreservation of PBSC in a novel intracellular-like, fully defined, serum- and protein-free preservation solution, CryoStor™ (BioLife Solutions, Inc.), with a standard formulation used by the Fred Hutchinson Cancer Research Center (FHCRC). Briefly, human PBSC apheresis specimens were collected and 5 × 107 cells/1 ml sample vial were prepared for cryopreservation in the following solutions: 1) FHCRC standard – Normosol-R, 5% HSA, 10% DMSO, and 2) CryoStor™ CS10 (final diluted conc. of 5% DMSO). A standard controlled-rate freezing program was employed, and frozen vials were stored in the vapor phase of a liquid nitrogen freezer for a minimum of one week. Vials were then thawed and evaluated for TNC, Viability, CD34, and granulocytes by flow cytometry, along with colony-forming activity in methylcellulose.
The PBSC samples frozen in CryoStor™ CS10 yielded significantly improved post-thaw recoveries for total viable CD34+, CFU, and viable granulocytes. Specifically, relative to the FHCRC standard formulation, cryopreservation with CS10 resulted in an average 1.8 fold increased recovery of viable CD34+ cells (P = 0.005), a 1.5 fold increase in CFU-GM numbers (P = 0.030), and a 2.3 fold increase in granulocyte recovery (P = 0.045).
This study indicates that use of CryoStor™ for cryopreservation can yield significantly improved recovery and in vitro functionality of the stem/progenitor cells in PBSC products. In addition, it is important to note that these improved recoveries were obtained while also not introducing any extra serum or serum-derived proteins, and reducing the final concentration/volume of DMSO by half. Further in vitro and in vivo studies are clearly necessary, however these findings imply use of CryoStor™ for cryopreservation might ultimately result in improved engraftment for those patients with lower content of CD34+ cells in their PBSC collections, along with reducing the requirement for additional apheresis collections, and decreasing the risk of adverse infusion reactions associated with higher exposure to DMSO.
Cryopreservation; CryoStor; CD34+; CFU-GM; PBSC
We investigated the effect and outcome of allogeneic peripheral blood stem cell (PBSC) rescue for aplastic anemia (AA) patients with graft failure after allogeneic bone marrow transplantation (BMT). Seven (28%) of 25 AA patients who received BMT from HLA-identical sibling donors developed late graft failure at a median of 7 months (range, 2.0-9.3 months) after transplantation. The patients with graft failure were treated with PBSC collected from the original donor after mobilization with granulocyte-colony stimulating factor (G-CSF). The median boost dose of peripheral blood mononuclear cells was 3.1 x 10(8)/kg (range, 1.4-11.9 x 10(8)/kg). Median times to reach an absolute neutrophil count greater than 0.5 x 10(9)/L and a platelet count greater than 50 x 10(9)/L were 7 days (range, 4-14 days) and 9 days (range, 3-41 days), respectively. There was sustained graft function in 6 of 7 patients, with a median follow-up duration of 3.3 yr (range, 1.0-6.2 yr). Grade-I acute graft-versus-host disease (GVHD) occurred in 2 patients, while extensive chronic GVHD developed in 3 patients. This report shows that G-CSF-mobilized allogeneic PBSC rescue is very effective in achieving complete and sustained engraftment in patients with AA after graft failure. However, more efficacious measures to prevent extensive chronic GVHD remain to be developed.
Few studies have tested the benefits of using peripheral blood stem cell (PBSC) grafts versus bone marrow (BM) grafts for unrelated donor transplantation. Yet there has been a substantial change in clinical practice, with increasing numbers of adults receiving unrelated donor PBSC grafts. We compared outcomes after 331 PBSC and 586 BM transplants in adults with leukemia and myelodysplastic syndrome who were followed for a median of 3 years after transplantation. PBSC recipients were less likely to have chronic myeloid leukemia and more likely to have myelodysplastic syndrome, to have poor performance scores and to be transplanted more recently. Outcomes were analyzed using Cox regression models. Rates of grades 2–4 acute graft-versus-host disease (GVHD) (58% vs. 45%, p<0.001) and chronic GVHD (56% vs. 42%, p<0.001) were significantly higher with PBSC than with BM transplants. Rates of grade 3–4 acute GVHD were similar with PBSC and BM transplants. The 3-year probabilities of treatment-related mortality, leukemia recurrence, leukemia-free and overall survival were similar in the two groups with 3-year leukemia-free survival rates of 30% and 32% after transplantation of PBSC and BM, respectively. Unlike results after HLA-matched sibling donor PBSC transplants, we did not identify a survival advantage with PBSC grafts in patients receiving unrelated donor transplants for advanced leukemia. The higher rate of chronic GVHD after PBSC transplants and, consequently, more frequent late adverse events warrant extended follow up of PBSC recipients.
peripheral blood graft; graft-versus-host disease; unrelated donor transplant
Lenalidomide (LEN) is a relatively new and very effective therapy for multiple myeloma (MM). Prior LEN therapy is associated with an increased risk of peripheral blood stem cell collection (PBSC) failure, particularly with filgrastim (G-CSF) alone. We performed a retrospective chart review of 319 consecutive MM patients who underwent apheresis to collect PBSCs for the first autologous stem cell transplant (ASCT).
The median number of PBSCs collected in the LEN (+) group was significantly less than the LEN (−) group (6.34 vs. 7.52×106 CD34+ cells/kg; p=0.0004). In addition, the median number of apheresis sessions required for adequate PBSCs collection were significantly more in the LEN (+) group as compared to LEN (−) group (2 vs. 1 sessions; p=0.002). In the LEN (+) group, there was a negative correlation between PBSCs collected and prior number of cycles of LEN (p=0.0001). Rate of PBSC collection failure was 9 % in the LEN (+) group and 5 % in the LEN (−) group (p=0.16). Only six patients who failed PBSC collection with G-CSF were able to collect adequate PBSCs with G-CSF + plerixafor. LEN exposure had no effect on neutrophil or platelet recovery post-ASCT.
Up to four cycles of LEN exposure have minimal negative impact on PBSC collection. Despite prolong exposure of LEN, PBSC collection was adequate for two ASCTs in the majority of patients and post-ASCT engraftment was not longer than expected; however, clinical relevance (complication rate, quality of life, cost) of prolonged LEN exposure on both PBSC and ASCT, should be evaluated in prospective clinical trials.
Lenalidomide; Multiple myeloma; Peripheral stem cells collection
To carry out a phase I‐II trial to elucidate the feasibility and efficacy of high dose cyclophosphamide (CY) supported by autologous peripheral blood stem cell transplantation (PBSCT) in the treatment of severe and refractory autoimmune disease (AD).
Peripheral blood stem cells (PBSCs) were mobilised during haematological recovery after relatively high dose CY (2 g/m2) for 2 days, followed by administration of granulocyte colony stimulating factor. After collecting PBSCs—more than 2×106 CD34+ cells/kg—by apheresis, CD34+ cells were immunologically selected and cryopreserved. Eight patients were enrolled—five had systemic sclerosis (SSc) alone, one had SSc with systemic lupus erythematosus, one amyopathic dermatomyositis (ADM), and one Wegener's granulomatosis (WG). All of the patients were treated with high dose CY (50 mg/kg) for 4 days and autologous PBSCT.
Haematopoietic reconstitution was rapid and sustained. Toxicity due to the regimen included various infections such as pneumonia, sepsis, cystitis, herpes zoster, and acute heart failure. However, there was no treatment related mortality. Encouraging results were obtained after autologous PBSCT. Sclerosis of the skin was markedly improved in all of the patients with SSc. Interstitial pneumonia (IP), evaluated by Pao2, serum KL‐6 levels, and pulmonary high resolution computed tomography, improved significantly. In a patient with ADM, severe and progressive IP also improved markedly. In a patient with WG, the size of the left orbital granuloma decreased substantially, resulting in reduction of the exophthalmos.
These observations suggest that high dose CY with autologous PBSCT is feasible and may be effective in the treatment of severe and refractory AD.
autoimmune disease; high dose cyclophosphamide; interstitial pneumonia; transplantation; Wegener's granulomatosis
Hematopoietic stem cell transplant (HSCT) is a standard treatment for many hematological malignancies. Three different sources of stem cells, namely bone marrow (BM), peripheral blood stem cells (PBSC) and cord blood (CB) can be used for HSCT, and each has its own advantages and disadvantages. Randomized controlled trials (RCTs) suggest that there is no significant survival advantage of PBSC over BM in Human Leukocyte Antigen-matched sibling transplant for adult patients with hematological malignancies. PBSC transplant probably results in lower risk of relapse and hence better disease-free survival, especially in patients with high risk disease at the expense of higher risks of both severe acute and chronic graft-versus-host disease (GVHD). In the unrelated donor setting, the only RCT available suggests that PBSC and BM result in comparable overall and disease-free survivals in patients with hematological malignancies; and PBSC transplant results in lower risk of graft failure and higher risk of chronic GVHD. High level evidence is not available for CB in comparison to BM or PBSC. The risks and benefits of different sources of stem cells likely change with different conditioning regimen, strategies for prophylaxis and treatment of GVHD and manipulation of grafts. The recent success and rapid advance of double CB transplant and haploidentical BM and PBSC transplants further complicate the selection of stem cell source. Optimal selection requires careful weighing of the risks and benefits of different stem cell source for each individual recipient and donor. Detailed counseling of patient and donor regarding risks and benefits in the specific context of the patient and transplant method is essential for informed decision making.
Hematopoietic stem cell transplantation; Bone marrow; Peripheral blood stem cell; Cord blood; Hematological malignancy
Stem-cell therapy represents a promising strategy for the treatment of challenging pathologies, such as large, infected wounds that are unresponsive to conventional therapies. The present study describes the clinical application of peripheral blood stem cells (PBSCs) for the treatment of four adult Warmblood horses with naturally occurring wounds, which were unresponsive to conventional therapies for at least 3 months. A visual assessment was performed, and a number of wound-healing parameters (granulation tissue, crust formation and scar formation) were evaluated. In all cases, tissue overgrowth was visible within 4 weeks after PBSC injection, followed by the formation of crusts and small scars in the centre of the wound, with hair regeneration at the edges. In conclusion, this is the first report of PBSC therapy of skin wounds in horses, and it produced a positive visual and clinical outcome.
Allogeneic bone marrow (BM) and cytokine mobilized peripheral blood stem cell (PBSC) transplantation can be curative for patients with malignant and nonmalignant hematologic diseases. Siblings are most often selected as a donor match; however, research on sibling donors is limited and has focused primarily on conventional BM donors. This exploratory study describes the experiences of PBSC sibling donors at a single institution. Through retrospective interviews, 14 sibling donors shared their perceived needs and concerns before and after their stem cell collection. Donors identified fears about the donation procedure, and expressed the need for more information about transplant outcome and complications. The inclusion of the sibling donors themselves, rather than the report of their parents or health-care providers and the qualitative nature of the structured design allowed sibling donors to describe their concerns and thoughts without being restrained by the beliefs of the participant’s parents, researcher or sibling’s medical team. Suggestions for visual educational tools, psychosocial interventions and future research are provided.
hematopoietic stem cell transplantation; bone marrow and peripheral blood stem cell transplantation; pediatric sibling donors; psychosocial adjustment
Poor outcome in Stage 4 neuroblastoma may be improved with increased dose intensity of therapy. We investigated the feasibility of sequential collection and infusion of peripheral blood stem cells (PBSC) as hematopoietic support for non-myeloablative dose intensive induction chemotherapy given every 21-28 days.
Twenty-two children with Stage 4 neuroblastoma (≥ 1yr of age) received 2 cycles of high dose cyclophosphamide (4 gm/m2), doxorubicin (75mg/m2) and vincristine (2mg/m2) followed by 3 cycles of interpatient dose escalating carboplatin (dose level 0 = 800 mg/m2; dose level 1 = 1000 mg/m2), high dose cyclophosphamide (4 gm/m2) and etoposide (600 mg/m2). PBSC were harvested following cycle 2, 3, and 4 in Cohort 1 and infused after each subsequent cycle. In Cohort 2, PBSC were harvested after cycle 2 and split into 3 aliquots for infusion. Dose limiting toxicity (DLT) and ability to administer cycles within 28 days was assessed.
Sufficient PBSC (≥ 2 × 106 CD34 cells/kg per infusion) were collected from 17/21 eligible patients with minimal toxicity and no detectable neuroblastoma cells by immunocytology. Carboplatin at 1000 mg/m2 resulted in DLT of delayed platelet recovery > 28 days in 4/8 patients. Despite de-escalation to 800 mg/m2, platelet DLT occurred in 4/7 Cohort 1 and 3/7 Cohort 2 patients.
As defined in this protocol, doses of carboplatin were not tolerable with the PBSC dose administered. However, it was feasible to collect sufficient PBSC from small neuroblastoma patients to use as hematopoietic support with minimal risk of tumor contamination and toxicity.
neuroblastoma; peripheral blood stem cell support; dose intensity; carboplatin
Peripheral blood stem cell (PBSC) products contain more T cells and monocytes when compared to bone marrow (BM), leading to fewer bacterial and fungal infections. CMV viral load and disease as well as CMV-specific immune reconstitution were compared in patients enrolled in a randomized trial comparing PSBC and BM transplantation. There was a higher rate of CMV infection and disease during the first 100 days after transplantation among PBSC recipients (any antigenemia/DNAemia: PBSC, 63% vs. BM, 42%, P=0.04; CMV disease: PBSC, 17% vs. BM, 4%, P=0.03). By two years, CMV disease rates were similar. The early increase in CMV events correlated temporarily with lower CMV-specific CD4+ T helper and CD8+ cytotoxic T lymphocyte function at 30 days after transplantation in PBSC recipients. By 3 months after transplantation and thereafter, CMV-specific immune responses were similar between BM and PBSC recipients. In conclusion, higher CMV infection and disease rates occurred in PBSC transplant recipients early after transplantation. These differences may be due to a transient delay in CMV specific immune reconstitution following PBSC transplantation.
Some men with metastatic germ cell tumours that have progressed after response to initial cisplatin-based combination chemotherapy are cured with conventional dose first salvage chemotherapy (CDCT) – however, many are not. High-dose chemotherapy with autologous stem cell rescue (HDCT) may be of value in these patients. Prognosis has recently been better defined by International Prognostic Factor Study Group (IPFSG) prognostic factors. HDCT after response to CDCT has been offered at our institution over the past two decades. We retrospectively assessed the validity of the IPFSG prognostic factors in our patients and evaluated the value of HDCT.
We identified eligible men with metastatic germ cell tumour progressed after at least 3 cycles of cisplatin-based chemotherapy and treated with cisplatin-based CDCT alone or with carboplatin-based HDCT. We also collected their clinical data. Patients were classified into risk groups using IPFSG factors, and progression-free and overall survival factors were analyzed and compared in patients treated with CDCT alone and with HDCT.
We identified 38 eligible first salvage patients who had received a median of 4 cycles (range, 1 to 7 cycles) of CDCT. Twenty patients received CDCT alone and 18 patients received CDCT plus HDCT. The overall median progression- free survival was 24.6 months (95%CI, 7.3 to 28.7 months) and overall median overall survival was 34.6 months (95%CI, 17.2 to 51.3 months). Distribution by IPFSG category and 2-year progression- free survival and 3-year overall survival rates within each risk category were very similar to the IPFSG results. There were two toxic deaths with CDCT and none with HDCT. Overall, patients treated with CDCT plus HDCT had improved progression- free survival and overall survival.
The IPFSG prognostic risk factors appeared valid in our patient population. The safety of HDCT with etoposide and carboplatin was confirmed. HDCT was associated with improved progression- free survival and overall survival outcomes, consistent with observations of the IPFSG group. Ideally, the value of optimal HDCT should be determined in comparison to optimal CDCT as first salvage therapy in men with metastatic germ cell tumour with a randomized trial.
We have previously observed that donor bone marrow hematopoietic stem cells successfully induce transient mixed chimerism and renal allograft tolerance following non-myeloablative conditioning of the recipient. Stem cells isolated from the peripheral blood (PBSC) may provide similar benefits. We sought to determine the most effective method of mobilizing PBSC for this approach and the effects of differing conditioning regimens on their engraftment.
A standard dose (10 μg/kg) or high dose (100 μg/kg) of granulocyte colony-stimulating factor (GCSF) with or without stem cell factor (SCF) was administered to the donor and PBSC were collected by leukapheresis. Cynomolgus monkey recipients underwent a nonmyeloablative conditioning regimen (total body irradiation, thymic irradiation and ATG) with splenectomy (splenectomy group) or a short course of anti-CD154 antibody (aCD154) (aCD154 group). Recipients then received combined kidney and PBSC transplantation and a one-month post transplant course of cyclosporine.
Treatments with either two cytokines (GCSF+SCF) or high dose GCSF provided significantly more hematopoietic progenitor cells than standard dose GCSF alone. Recipients in the aCD154 group developed significantly higher myeloid and lymphoid chimerism (p<0.0001 and p=0.0002, respectively) than those in the splenectomy group. Longer term renal allograft survival without immunosuppression was also observed in the aCD154 group, while two of three recipients in the splenectomy group rejected their allografts soon after discontinuation of immunosuppression.
Protocols including administration of two cytokines (GCSF + SCF) or high dose GCSF alone significantly mobilized more PBSC than standard dose GCSF alone. The recipients of PBSC consistently developed excellent chimerism and survived long-term without immunosuppression, when treated with CD154 blockade.
kidney transplantation; nonhuman primates; tolerance; mixed chimerism; peripheral blood stem cell transplantation; leukapheresis
We report a prospective phase II clinical trial in 35 adult patients (median age 40.5 years) with hematologic malignancies who received T-cell depleted, hematopoietic stem cell transplants from HLA-compatible, unrelated donors. The cytoreductive regimen consisted of hyperfractionated total body irradiation, thiotepa, and fludarabine. The preferred graft source was G-CSF-mobilized peripheral blood stem cells (PBSC). PBSC were CD34+ selected, followed by sheep erythrocyte rosetting to deplete residual T cells. Antithymocyte globulin provided graft rejection prophylaxis. No additional graft versus host disease (GvHD) prophylaxis was planned. Estimated disease free survival at 4 years is 56.8% for the entire group and 75% in patients with standard risk disease. The cumulative incidence of relapse is 6%. Acute GvHD grade II-III developed in 9% and chronic GvHD in 29% of patients. Fatal infections occurred in 5 of 35 (14%) patients. There was one late graft failure. This study demonstrates durable engraftment with a low overall incidence of GvHD. Its curative potential is reflected in the remarkably low relapse rate at 4 years.
In 29 chemotherapy-naive patients with stage II-III breast cancer, peripheral blood stem cells (PBSCs) were mobilised following fluorouracil 500 mg m-2, epirubicin 90-120 mg m-2 and cyclophosphamide 500 mg m-2 (FEC) and granulocyte colony-stimulating factor (G-CSF; Filgrastim) 300 microgram s.c. daily. In all but one patient, mobilisation was successful, requiring three or fewer leucocytopheresis sessions in 26 patients; 28 patients subsequently underwent high-dose chemotherapy consisting of carboplatin 1600 mg m-2, thiotepa 480 mg m-2 and cyclophosphamide 6 g m-2 (CTC) followed by PBSC transplantation. Haemopoietic engraftment was rapid with a median time to neutrophils of 500 x 10(6) l(-1) of 9 days (range 8-10) in patients who received G-CSF after PBSC-transplantation; platelet transfusion independence was reached within a median of 10 days (range 7-16). Neutropenic fever occurred in 96% of patients. Gastrointestinal toxicity was substantial but reversible. Renal, neural or ototoxicity was not observed. Complications related to the central venous catheter were encountered in 64% of patients, with major vein thrombosis occurring in 18%. High-dose CTC-chemotherapy with PBSC-transplantation, harvested after mobilisation with FEC and G-CSF, is reasonably well tolerated without life-threatening toxicity and is a suitable high-dose strategy for the adjuvant treatment of breast cancer.
Allogeneic bone marrow transplantation (BMT) under costimulation blockade allows induction of mixed chimerism and tolerance without global T cell depletion. The mildest such protocols without recipient cytoreduction, however, require clinically impracticable bone marrow (BM) doses. The successful use of mobilized peripheral blood stem cells (PBSC) instead of BM in such regimens would provide a substantial advance, allowing transplantation of higher doses of hematopoietic donor cells. We thus transplanted fully allogeneic murine granulocyte colony-stimulating-factor (G-CSF) mobilized PBSC under costimulation blockade (anti-CD40L and CTLA4Ig). Unexpectedly, PBSC did not engraft, even when very high cell doses together with non-myeloablative total body irradiation (TBI) were used. We show that, paradoxically, T cells contained in the donor PBSC triggered rejection of the transplanted donor cells. Rejection of donor bone marrow was also triggered by the co-transplantation of unmanipulated donor T cells isolated from naïve (non-mobilized) donors. Donor-specific transfusion and transient immunosuppression prevented PBSC-triggered rejection and mixed chimerism and tolerance were achieved, but graft-versus-host disease (GVHD) occurred. The combination of in vivo T cell depletion with costimulation blockade prevented rejection and GVHD. Thus, if allogeneic PBSC are transplanted instead of BM, costimulation blockade alone does not induce chimerism and tolerance without unacceptable GVHD-toxicity, and the addition of T cell depletion is required for success.
mixed chimerism; tolerance; costimulation blockade; PBSC