Rapid Hematopoietic Reconstitution Research Articles

The simplification of the SCT procedures in developing countries has resulted in cost-lowering and availability to more patients.

In order to simplify and cutting down expenses of the bone marrow transplantation procedures we have made some efforts, trying to provide the best transplantation technique for the individual patient with scarce resources. In relation with the source of stem cells, we have found very attractive the use of peripheral blood stem cells (PBSC) instead of bone marrow cells. This procedure can produce substantially more rapid engraftment than observed with bone marrow. The rapid hematopoietic reconstitution in the recipient of PBSC lower expenses stemming from the use of antibiotics, blood bank products and days at the hospital. In Mexico, a country with a large number of cases of severe aplastic anemia we decided to use PBSC to transplant 10 patients with this disease, in order to take advantage of the large number of stem cells that this procedure can provide. We had excellent results in these patients, avoiding the high cost of the conventional transplantation and the use of ATG. In relation to autologous transplantation we have made efforts to perform autografts without the use of freezing devices, keeping the stem cells in liquid form using a conventional blood bank refrigerator for up to 96 hr. This modifications have resulted in diminishing costs and increasing the availability of the procedure to a large number of patients. Finally in Mexico we have had experience with non-myeloablative transplants, and obtained reasonably good results, with a median cost of 18,000 USD per allogeneic transplantation procedure. In some cases this is the only affordable therapeutic option. In developing countries where very few patients can afford the cost of conventional bone marrow transplants, any reasonable effort in the direction of simplification must be welcome.

Allogeneic peripheral blood stem cell transplantation for treatment of leukemia

To observe engraftment kinetics, incidence and severity of graft-versus-host disease (GVHD) and clinical outcome in 40 recipients undergoing allogeneic peripheral blood stem cell transplantation (allo-PBSCT). 40 leukemia patients with a median age of 35 years underwent allo-PBSCT from June 1997 to May 1999. PBSC were mobilized with G-CSF at a dose of 5 microg/kg S. C. every 12 hours for 5 days. A median of 7.7 (range 2.0 to 16.8) x 10(6) CD(34)(+) cells/kg was infused into the recipients. Busulfan (BU) and cyclophosphamide (CY) were used as conditioning regimen. All patients received cyclosporine A and either methotrexate (n = 34) or methylprednisolone (n = 6) for GVHD prophylaxis. Engraftment of neutrophils and platelets was achieved at a median of day + 13 (9 - 28) and day +12 (7 - 60) respectively. Patients receiving >or=4 x 10(6) CD(34)(+) cells/kg or given G-CSF post transplant had significantly accelerated neutrophil and platelet engraftment. Acute GVHD occurred in 17 of the 40 patients (42.5%), with grade II-IV acute GVHD in 10 patients (25.0%); chronic GVHD developed in 21 out of the 30 evaluable patients (70.0%) with a median follow up of 480 days (range 300 - 1,000). The transplant related mortality is 20.0% and the relapse rate is 10.0%. The probability of leukemia free survival at 3 years is 70.0%. These results indicate that allo-PBSCT can provide rapid hematopoietic reconstitution without an increased incidence of acute GVHD, but may be associated with high risk of chronic GVHD.

Reprise HéMatopoïéTique En Fonction Du Nombre De Cellules Cd34+ AutogrefféEs: ÉTude RéTrospective Chez 66 Patients Atteints D'HéMopathies Malignes

SummaryEngraftment in relation to infused CD34+ cell number was retrospectively analysed in 66 patients with hematological diseases: non-Hodgkin’s lymphoma (n = 33), multiple myeloma (n = 21), acute myelogenous leukemia (n = 7), Hodgkin’s disease (n = 4) and myelodysplastic syndrome (n = 1). Progenitor cells were mobilized with rhG-CSF, alone or in association with chemotherapy. The cells were harvested by leukapheresis until at least 2 Ö 106 CD34+/kg body weight were obtained. A total of 194 leukaphereses were performed (median = 3 per patient, range 1 - 9). A median of 3.40 × 108 nucleated cells/kg (range 0.31 - 27.59) and a median of 7.15 × 106 CD34+ cell /kg (range 1.31 - 115.70) were transplanted. Regardless of transfusional support or patient diagnosis, engraftment was rapid in patients who had received > 5 × 106 CD34+ cell /kg. In this case, absolute neutrophil blood count > 0.5 × 109/1 was obtained on day 12 post graft (range 7-19) and platelet count ≥ 20 × l09/l was also reached after the same median time interval (range 8 - 121). From the present results, a minimal threshold of 5 × 106 CD34+ cell /kg appears to be suitable for providing rapid and com-plete hematopoietic reconstitution in patients exposed to high doses of chemotherapy with or without total body irradiation. Furthermore, administration of rhG-CSF during post-graft period significantly decreased the neutrophil time recovery (P = 0.002) but not that of platelets (P > 0.05).

Thrombocytopenia after high-dose chemotherapy and autologous stem cell transplantation: an unresolved problem and possible approaches to resolve it.

Prolonged thrombocytopenia is a frequent clinical problem in cancer patients undergoing high-dose chemotherapy and autologous transplantation. The use of GM-CSF as an adjuvant to autologous bone marrow transplantation (ABMT) has significantly reduced the duration of neutropenia after high-dose chemotherapy but failed to accelerate platelet recovery in transplanted patients. The more rapid hematopoietic reconstitution obtained by autologous mobilized peripheral blood progenitor cell transplantation (PBPCT) after high-dose chemotherapy has resulted in its increasing use instead of ABMT. However, PBPCT does not always produce faster platelet engraftment after high-dose chemotherapy, and persistent thrombocytopenia remains a significant clinical problem in PBPC-transplanted patients. The duration of severe thrombocytopenia (requiring frequent platelet transfusions) until platelet recovery varies widely depending on the quality of the autograft and previous radiotherapy or chemotherapy. The median days to reach 20,000/microliters platelets ranged from 10 to 32 days. Pilot clinical studies in which cancer patients were transplanted with enriched CD34+ cell autografts, obtained from G-CSF-mobilized PB, showed a similar platelet recovery after high-dose chemotherapy but also wide variation among the patients. The median days to reach 20,000/microliters platelets ranged from 9 to 38 days. The dose of CFU-GM in the autograft has been identified as the best predictive factor for hematopoietic recovery (p < 0.0001) after high-dose chemotherapy and autologous PBPCT in 118 patients with hematologic malignancies. A similar assessment of the megakaryocyte progenitor cells (BFU-MK and CFU-MK) in the autograft not only could predict time to platelet recovery but also could help to optimize the number and method of mobilization of the PBPC required to shorten the problematic obligatory 2-week duration of thrombocytopenia after high-dose chemotherapy. A routine assessment of the number of BFU-MK and CFU-MK present in each autograft and correlation with platelet recovery after transplantation would enable us to define the clinical threshold cell dose required for rapid platelet recovery. Recently, several non-specific cytokines with thrombopoietic activity have been evaluated in phase I clinical trials, including interleukin-1, interleukin-3 followed by GM-CSF, interleukin-6, and interleukin-11 in cancer patients, showing an encouraging trend toward a decrease in thrombocytopenia after chemotherapy. The recently cloned specific platelet cytokine, thrombopoietin, is currently undergoing phase I clinical studies, and the results are awaited with interest.

Factors for rapid and sustained hematopoietic reconstitution by circulating progenitor-cell transplantation in non-Hodgkin’s lymphoma

Factors for rapid and sustained hematopoietic reconstitution by circulating progenitor-cell transplantation in non-Hodgkin’s lymphoma

1133 Comparison between CD34+ cells and CFU-GM growth in leukapheretic products of patients undergoing CPC transplant

An extremely rapid and complete hematopoietic reconstitution occurs in patients receiving high dose chemotherapy when circulating progenitor cells (CPC), collected by leukapheresis, rather than marrow-derived cells, are reinfused. The amount of progenitor cells collected, which correlates with the speed of bone marrow reconstitution, is usually evaluated by the number of CD34+ cells and/or the number of clonogenic cells (CFU-GM). Since not all investigators agree with the correlation between these two parameters, we have compared CFU-GM growth and CD34+ cells in 27 leukapheresis from patients with solid tumors undergoing CPC transplantation. In our study a clear correlation between the two assays was shown (see fig. below) and we conclude that there is no need to perform both of them. Since CD34+ assay is simpler, less time-consuming and can be completed in a few hours versus weeks, we now perform only immunophenotypic analysis for clinical decision making. Download : Download high-res image (48KB) Download : Download full-size image

Collection of mobilized blood progenitor cells for hematopoietic rescue by large-volume leukapheresis.

Mobilized blood progenitor cells rapidly reconstitute hematopoiesis in patients after dose-intensive chemotherapy. However, optimal timing and methods of mobilized blood progenitor cell collection have yet to be fully defined. The utility of large-volume leukapheresis (LVL; > 15 L blood processed) in collecting target doses of mononuclear cells (7 x 10(8)/kg) for use in autologous hematopoietic rescue was investigated. LVL was begun at a standardized interval (14 days) after a course of limited chemotherapy and subsequent daily recombinant human granulocyte-macrophage-colony-stimulating factor administration to mobilize blood progenitor cells into the circulation. With each LVL procedure, mononuclear cells, colony-forming units-granulocyte-macrophage (CFU-GM), burst-forming units-erythroid, mixed colonies, total clonogenic progenitor cells, and CD34+ cells collected per kg of patient weight were counted. After high-dose chemotherapy and infusion of cryopreserved mobilized blood progenitor cells, the days needed for neutrophils to reach levels of > 0.5 x 10(9) per L and for platelets to reach levels of > 20 x 10(9) per L were recorded. In 14 previously treated cancer patients, an average of 28.9 +/- 4.9 L of blood was processed per LVL (n = 35) to collect medians of 2.5 x 10(8) mononuclear cells per kg (range, 1.0-7.4), 14 x 10(4) CFU-GM per kg (0-208), 27 x 10(4) clonogenic progenitor cells per kg (0-370), and 2.8 x 10(6) CD34+ cells per kg (0-112.5). Fifty-seven percent of patients (8/14) required one or two LVL procedures to collect adequate blood progenitor cells (range, 1-4). After dose-intensive chemotherapy, 13 patients received medians of 6.8 x 10(8) mononuclear cells per kg (range, 5.1-9.9), 53 x 10(4) CFU-GM per kg (9-208), and 12 x 10(6) CD34+ cells per kg (3.6-112.5). Rapid hematopoietic reconstitution occurred with 10 days (range, 8-12) and 9 days (6-15), respectively, for neutrophil and platelet recoveries. Scheduled LVL, beginning on Day 14 after the administration of granulocyte-macrophage-colony-stimulating factor following chemotherapy, is a convenient and efficient method of collecting blood progenitor cells. The mononuclear cells so obtained effected consistent and rapid hematopoietic reconstitution in a highly reproducible manner in a group of heavily treated patients.

Transplantation of Allogeneic Peripheral Blood Stem Cells Mobilized by Recombinant Human Granulocyte Colony-Stimulating Factor

Peripheral blood stem cells (PBSCs) are widely used in autologous transplantation because of ease of collection and rapid hematopoietic reconstitution. However, PBSCs have rarely been used for allogeneic transplantation because of concerns about donor toxicities from cytokine administration and the theoretical increased risk of graft-versus-host-disease (GVHD) from the large number of T cells infused. Eight patients with advanced malignancies received allogeneic PBSC transplants from genotypically HLA-identical sibling donors. All donors received 5 days of recombinant human granulocyte colony-stimulating factor (rhG-CSF; 16 micrograms/kg/day) subcutaneously and were leukapheresed for 2 days. After treatment of the patient with total body irradiation and cyclophosphamide (n = 7) or etoposide, thiotepa, and cyclophosphamide (n = 1), PBSCs were infused immediately after collection and without modification. All patients received cyclosporine and either methotrexate (n = 6) or prednisone (n = 2) for GVHD prophylaxis, rhG-CSF was well tolerated with mild bone pain requiring acetaminophen occurring in two donors. All patients engrafted and in seven hematopoietic recovery was rapid, with 500 neutrophils/microL achieved by day 18 and 20,000 platelets/microL by day 12. Complete donor engraftment was documented by Y chromosome analysis in all four sex-mismatched donor-recipient pairs tested and by DNA analysis in two sex-matched pairs. One patient died on day 18 of veno-occlusive disease of the liver with engraftment but before chromosome analysis could be performed (results are pending in 1 patient). A second patient died of fungal infection 78 days after transplant. Grade 2 acute GVHD occurred in two patients and grade 3 GVHD occurred in one patient. One patient is 301 days from transplant in remission with chronic GVHD; the remaining five patients are alive and disease free 67 to 112 days after transplantation. Preliminary results indicate that allogeneic PBSCs mobilized by rhG-CSF can provide rapid hematologic recovery without an appreciably greater incidence of acute GVHD than would be expected with marrow. Further follow-up is required to determine the incidence of chronic GVHD and any potential beneficial effects on relapse after transplant.

Mobilized blood stem cells: immunophenotyping and functional characteristics.

High levels of peripheral blood stem cells (PBSC) can be collected from patients with hematopoietic malignancies or solid tumors after high-dose chemotherapy and/or growth factors. Rapid, complete, and durable hematopoietic reconstitution has been observed in patients who have been transplanted with PBSC after conditioning with supralethal myeloablative therapy. We will review the recent data concerning the immunophenotype and functional capacities of mobilized blood stem cells. PBSC seem to be comprised of a mixture of primitive and committed hematopoietic progenitors and are not that different from bone marrow-derived stem cells.

Autologous bone marrow transplantation in acute myeloid leukemia in first remission: results of a Dutch prospective study.

Recent investigations have suggested a role for marrow ablative chemotherapy and radiotherapy given with autologous bone marrow transplantation (auto-BMT) in the treatment of acute myeloid leukemia (AML), but prospective studies have not been reported. We assessed the comparative values of auto-BMT and allogeneic marrow transplantation (allo-BMT) in 117 15- to 60-year-old consecutive patients (median, 43 years) with AML following remission-induction therapy. In 32 cases of the 90 (77%) complete responders, auto-BMT (nonpurged) was undertaken at a median of 3.8 months and in 23 eligible cases human leukocyte antigen (HLA)-matched allo-BMT occurred at 3.0 months after attainment of remission. Thus, nearly 60% of complete responders had access to transplantation, the others being withdrawn because of relapse, refusal, or other causes. Median time of regeneration to neutrophils 0.5 x 10(9)/L and platelets 20 x 10(9)/L were 39 and 63 days following auto-BMT versus 21 and 19 days after allo-BMT, respectively. AML relapse was the predominant cause of failure after auto-BMT (17 of 32) and procedure-related death was seen in three of 32 patients. The actuarial rates of relapse at 3 years are 60% (auto-BMT) and 34% (allo-BMT) (log-rank, P = .03). Patients treated with auto-BMT and allo-BMT have an overall survival of 37% and 66% at 3 years posttransplant, respectively (P = .05). Relapse-free 3-year survival rates are 35% and 51%, respectively (P = .12). Survival of the nongrafted complete responders is less than 10%. This study shows that allo-BMT in adult patients with AML in first complete remission (CR) results in more rapid hematopoietic reconstitution, is followed by fewer recurrences, and provides better survival than auto-BMT.

Autologous Rescue with Blood-Derived Stem Cells in a Child with Non-Hodckin'S Lymphoma

Autologous blood-derived stem cells were used for stem-cell rescue in a 5-year-old boy with chemotherapy-resistant B-Non-Hodgkin's lymphoma (B-NHL) involving bone marrow. The high dose chemoradiotherapy was carried out 5 months after initial diagnosis during partial remission. The preparative regimen consisted of 12 Gy fractionated, total-body irradiation (FTBI) before 60 mg/kg etoposide. There were 22.96 X 10(4)/kg body weight myeloid precursor cells, granulocyte-macrophage committed stem cells (CFU-GM) collected by intermittent blood flow separation with a Haemonetics 30R in two cytaphereses and stored in liquid nitrogen. Also 11, 82 X 10(4) CFU-GM/kg body weight were recovered and transfused after thawing. Rapid hematopoietic reconstitution ensued: Erythroid precursors were detected on day 9, 1 X 10(9)/L leucocytes were counted on day 11, and 0.5 X 10(9)/L granulocytes on day 13, respectively. The patient required 3 single-donor platelet transfusions, the last one on day 10. On day 17, 100 X 10(9)/L platelets were reached. A bone marrow aspirate on the same day showed good trilineage regeneration. The patient remained in complete remission 7 months after autografting with a normal stem cell content of the bone marrow and in the peripheral blood. On day 226, after stem cell infusion, a bone marrow relapse occurred.