Comparison of marrow and blood cell yields from the same donors in a double-blind, randomized study of allogeneic marrow vs blood stem cell transplantation

Forty healthy adult donors underwent marrow (BM) as well as peripheral blood (PBSC) stem cell collections for their HLA-identical adult siblings with hematologic malignancies. BM was harvested on day 1 (target 3 x 108 nucleated cells/kg, 10 microg/kg lenograstim (glycosylated G-CSF) administered on days 2-6, and a single leukapheresis performed on day 6. The blood volume processed was the higher of 200% donor blood volume or 10 liters. The total nucleated cell (TNC) yields from PBSC were 1.1- to 4.3-fold higher than BM (median 7.0 vs 3.1 x 10(8)/kg, P < 0.0001). Although BM contained a higher proportion of CD34+cells (1.3% vs 0.7%, P < 0. 0001) and a comparable proportion of CD3+ cells (median 29% vs 26%, P = 0.4), the absolute numbers of CD34+ and CD3+ cells and their subsets were several times higher in PBSC. There was a poor correlation between BM and PBSC CD34 and TNC numbers, but a significant correlation between BM and PBSC CD3 numbers. Only five of 40 BM harvests contained >/=2 x 10(6) CD34+ cells/kg compared with 35 of 40 PBSC harvests (P < 0.0001). We conclude that the numbers of progenitor and immunocompetent cells in PBSC are several times higher than in BM. It is possible to collect adequate numbers of progenitor cells from blood after lenograstim stimulation more frequently than from marrow, and donors yielding low quantities of progenitor cells from BM usually deliver better quantities from PBSC. Bone Marrow Transplantation (2000) 25, 501-505.     

A randomized phase III clinical trial of autologous blood stem cell transplantation comparing cryopreservation using dimethylsulfoxide vs dimethylsulfoxide with hydroxyethylstarch

Hematopoietic stem cells intended for autologous transplantation are usually cryopreserved in solutions containing 10% dimethylsulfoxide (DMSO, v/v) or 5% DMSO in combination with 6% hydroxyethylstarch (HES, w/v). We performed a single-blinded, randomized study comparing these cryoprotectant solutions for patients undergoing autologous peripheral blood stem cell (PBSC) transplantation. A total of 294 patients were evaluable; 148 received cells frozen with 10% DMSO and 146 received cells frozen in 5% DMSO/6% HES. Patients who received cells frozen with the combination cryoprotectant recovered their white blood cell count >or=1.0 x 10(9)/l at a median of 10 days, one day faster than those who received PBSC frozen with DMSO alone (P=0.04). Time to achieve neutrophil counts of >or=0.5 x 10(9) and >or=1.0 x 10(9)/l were similarly faster for the recipients of the cells frozen in the combination solution. This effect was more pronounced for patients who received quantities of CD34+ cells higher than the median for the population. Median time to discontinuation of antibiotic use was also one day faster for the recipients of cells cryopreserved with DMSO/HES (P=0.04). In contrast, median times to recovery of platelet count >or=20 x 10(9)/l were equivalent for each group (10 days; P=0.99) and the median numbers of red cell and platelet transfusions did not differ.     

Peripheral blood vs bone marrow as a source for allogeneic hematopoietic stem cell transplantation.

In this randomized prospective study, we included 30 patients with different hematological diseases (acute myeloid leukemia, acute lymphoblastic leukemia, chronic myeloid leukemia, myelodysplastic syndrome or severe aplastic anemia) to compare peripheral blood stem cells (PBSC) (15 patients; mean age 23) and bone marrow (BM) (15 patients; mean age 21.8) as a source for allogeneic transplantation regarding the tempo of hematopoietic recovery and the incidence of acute graft-versus-host disease (GVHD). In the BM group, the median nucleated cell count harvested was 1.3 x 10(10), while in the PBSC group, the aphereses contained a median of 4.4 x 10(6) CD34+/kg recipient weight. PBSC transplantation (PBSCT) was associated with faster hematopoietic reconstitution measured as absolute neutrophil count (ANC) >0.5 x 10(9)/l (log-rank P value <0.0018) and platelet count >25 x 10(9)/l (log-rank P value <0.0098). Seven patients (46.7%) in the BM group vs only one patient (6.7%) in the PBSC group developed acute GVHD (P = 0.013). Therefore, we conclude that PBSCT is associated with faster hematopoietic recovery and the incidence of acute GVHD does not exceed that seen with BMT.     

Autologous bone marrow transplantation using unfractionated cells cryopreserved in dimethylsulfoxide and hydroxyethyl starch without controlled-rate freezing

To develop a simplified method of bone marrow (BM) cryopreservation, changes were made in the standard method in three areas: the cryoprotectant, the method of cell freezing, and the storage temperature. Unfractionated BM cells from 60 patients were cryopreserved in 300-mL aliquots in both dimethylsulfoxide (DMSO) and hydroxyethyl starch (HES), a combination known to preserve granulocytes successfully. The cells were frozen without rate-controlled freezing by simple immersion into a -80 degrees C freezer where they remained until the time of reinfusion. The 60 patients underwent 72 autologous transplants after three high-dose chemotherapy regimens: 30 received high-dose carmustine in combination, five received high-dose busulfan and cyclophosphamide, and 37 received high-dose aziridinylbenzoquinone. The BM was infused for more than 30 minutes after rapid thawing at 37 degrees C. The mean post-thaw nucleated cell recovery was 96% +/- 11.6%, and Trypan blue dye exclusion was 82.2% +/- 9.2%. The mean postthaw CFU-GM and BFU-E recoveries were 81.9% +/- 39.0% and 90.5% +/- 41.2%. Complete count recovery occurred in 68 of 72 transplants. Median times to a WBC count greater than 1,000/microL, a granulocyte count greater than 1,000/microL and a platelet count greater than 20,000/microL were 15, 21, and 15 days, respectively. Risk factors for delayed recovery were not found. Unfractionated BM cells can be successfully cryopreserved in the DMSO/HES mixture rapidly and inexpensively, without rate-controlled freezing or storage at liquid nitrogen temperatures.     

Transportation and cryopreservation may impair haematopoietic stem cell function and engraftment of allogeneic PBSCs, but not BM

Recent data suggest that the practice of using frozen allogeneic grafts is becoming increasingly common among transplant centres. Therefore, we retrospectively analysed 31 frozen allogeneic PBSC and 8 BM grafts by flow cytometry with regard to their CD34+ content, membrane integrity (7-AAD) and stem cell-specific enzyme activity (aldehyde dehydrogenase, ALDH) in relation to individual transplantation results. Membrane integrity of CD34+ cells was significantly impaired in cryopreserved PBSC but not in BM compared to unfrozen allografts. In 9 out of 31 frozen PBSC (but none of the BM) grafts numbers of SSC(lo)ALDH(br) cells per kg body weight (BW) were significantly reduced while in the same grafts the numbers of CD34+ cells per kg BW were close to normal. Overall, 9 out of 33 patients (27%) who received unrelated PBSC allografts cryopreserved after transportation did not achieve engraftment. For comparison, primary graft failure was observed in our centre in only 7 out of 493 recipients (1.4%) of fresh allogeneic PBSC grafts. Moreover, we did not see any graft failure in patients receiving frozen/thawed BM or autologous PBSC transplants. We, therefore, conclude that PBSC grafts become much more sensitive to cryopreservation after transport and/or storage. Importantly, the engraftment potential of frozen HSC grafts may reliably be predicted by measuring ALDH activity.     

Allogeneic hematopoietic transplantation of CD34+ selected cells from an HLA haplo-identical related donor. A long-term follow-up of 135 patients and a comparison of stem cell source between the bone marrow and the peripheral blood

We studied the outcome of allogeneic transplants in 135 patients who received selected BM and/or PBSC CD34+ cells from HLA haplo-identical related donors. Donor engraftment was achieved in 108 of 128 evaluable transplants. Engraftment failure occurred more often in non-malignant than in malignant diseases (10 of 25 vs 17 of 103, P = 0.010). The CD34+ cell dose was associated with the speed of neutrophil and platelet recovery, but the cell source was not. Acute GVHD (> or = grade II) developed in 21.0 +/- 3.7%. Chronic GVHD occurred more frequently in malignancies than in non-malignancies (44.1 +/- 7.6% vs 0.0%, P = 0.0075), and more in PBSC recipients than in BM recipients (53.6 +/- 9.4% vs 17.4 +/- 9.3%, P = 0.0054). Relapse rate was higher in high risk patients than in standard risk patients (78.7 +/- 7.1% vs 22.1 +/- 10.0%, P = 0.0001). Probabilities of disease-free survival (DFS) were 14.2 +/- 3.5% in malignancies and 25.7 +/- 9.2% in non-malignancies. Probabilities of DFS in standard and high risk patients were 39.4 +/- 9.2% and 5.7 +/- 2.8% (P = 0.0001). A high incidence of graft failure, infection and relapse was observed and resulted in high mortality.     

Purging in BCR-ABL-positive acute lymphoblastic leukemia using immunomagnetic beads: comparison of residual leukemia and purging efficiency in bone marrow vs peripheral blood stem cells by semiquantitative polymerase chain reaction

Twenty autologous bone marrow (BM) and 25 peripheral blood stem cell (PBSC) grafts were collected from a total of 40 consecutive patients with BCR-ABL+ acute lymphoblastic leukemia (ALL) in first (n = 37) or second (n = 3) complete morphological remission and subsequently purged with a cocktail of anti-CD19, -CD10, AB4 MoAbs and immunomagnetic beads (IMB). Residual BCR-ABL-positive cells before purging were detected in 19 of 20 BM grafts at a median of 4 (range 0-6) logs and in 17 of 25 evaluable PBSC grafts at a median of 1 (range 0-3) log above the limit of detection assessed by a semiquantitative limiting log10-dilution RT-PCR (P < 0.0001). IMB purging depleted a median of 2.5 (range 1-4) log of residual BCR-ABL+ cells from BM and a median of 1 (range 0-2) log from PBSC grafts, achieving RT-PCR negativity in 1/20 BM and 12/25 PBSC grafts after purging. Cell recoveries were 62% and 86% (P < 0.0001) of MNC and 74% and 97% (P = 0.065) of CD34+ cells after BM and PBSC purging, respectively. BM purging was superior using the triple MoAb cocktail which depleted 2.64 +/- 0.4 log (n = 14) compared to 1.6 +/- 0.4 log (n = 5) using the MoAb cocktail not including AB4 (P = 0. 02). We conclude that unpurged BM grafts contain 2-3 log more residual BCR-ABL+ cells than unpurged PBSC grafts and that purging efficacy is superior in BM compared to PBSC grafts, but median titers in purged BM grafts still exceed those in purged PBSC grafts. Bone Marrow Transplantation (2000) 25, 97-104.     

Allogeneic peripheral blood stem cell transplantation in patients with advanced hematologic malignancies: a retrospective comparison with marrow transplantation

Allogeneic peripheral blood stem cell (PBSC) transplants from HLA- identical siblings were performed in 37 patients with advanced hematologic malignancies. Outcomes were compared to a historical group of 37 similar patients with advanced hematologic malignancies receiving bone marrow (BM) transplants from HLA-identical donors. The PBSC group and historical BM group were well matched for diagnosis, disease stage, age, and graft-versus-host disease (GVHD) prophylaxis. Patients received PBSC transplants between 1993 to 1995 while BM patients were treated between 1989 to 1994. Engraftment, measured by the time to reach a peripheral neutrophil count > 500/L and platelet count > 20,000/microL without transfusions, occurred on days 14 and 11 in the patients transplanted with PBSC compared to days 16 and 15 in the patients receiving BM (P = .00063, .00014). The PBSC group required a median of 8 U of red blood cells and 24 U of platelets compared to 17 U of red blood cells and 118 U of platelets for BM transplant recipients (P = .0005, .0001). The estimated risks of developing grades 2 to 4 acute GVHD were 37% for the PBSC group and 56% for the BM group (P = .18), while the estimated risks of grades 3 to 4 acute GVHD were 14% for the PBSC group and 33% for the BM group, P = .05). Chronic GVHD occurred in 7 of 18 evaluable patients receiving PBSC and 6 of 23 evaluable patients receiving BM, P = .5. The estimated risks of transplant-related mortality at 200 days were 27% versus 45% (P = .33) relapse were 70% versus 53% (P = .27) and of overall survival were 50% and 41% (P = .39) for patients transplanted with PBSC or BM, respectively. This retrospective comparison suggests that compared to marrow transplantation from HLA-identical donors, allogeneic PBSC transplantation from HLA-identical donors is associated with faster engraftment, fewer transfusions, and no greater incidence of acute or chronic GVHD.     

Patients with acute lymphoblastic leukaemia allografted with a matched unrelated donor may have a lower survival with a peripheral blood stem cell graft compared to bone marrow

We analysed data for 213 patients with ALL and AML who received either peripheral blood stem cells (PBSC) (n=74) or bone marrow (BM) (n=139) from an HLA-matched unrelated donor (EBMT acute leukaemia registry; January 1994 to January 1999). The two groups of patients (by cell source) were comparable with respect to age, sex, disease status, year at transplant and graft T cell depletion. Engraftment was achieved in about 90% regardless of stem cell source or leukaemia type. Kinetics of neutrophil and platelet recovery, similar for both sources in ALL patients, were faster for PBSC in AML patients. The incidence of acute graft-versus-host disease was similar for both sources in AML patients, but higher for PBSC in ALL patients (74 vs 54%, P=0.05). The 1-year probability of chronic graft-versus-host disease was 40 and 45% (P=0.66) in ALL patients compared to 49 and 35% (P=0.13) in AML patients (PBSC vs BM). In AML patients, none of the following differed significantly with cell source: transplant-related mortality, relapse incidence, leukaemia-free survival and overall survival. In ALL patients, the transplant-related mortality for PBSC vs BM was 61 vs 47% (P=0.13), the relapse incidence was 47 vs 39% (P=0.17), the leukaemia-free survival was 21 vs 32% (P=0.04) and the overall survival was 24 vs 34% (P=0.04). These data suggest that the short-term outcome of allogeneic PBSC is not significantly different from that of BM in AML patients who underwent a transplant from a matched unrelated donor but, conversely, that survival with PBSC may be decreased in ALL patients. In conclusion, the source of transplant cells needs to be evaluated by disease, especially when dealing with unrelated donors.     

A simple, efficient washing procedure for cryopreserved human hematopoietic stem cells prior to reinfusion.

We describe our experience with a washing procedure used on cryopreserved, thawed bone marrow (BM) and peripheral blood stem cell (PBSC) grafts prior to autologous transplantation in 50 and 12 patients respectively. The procedure consists of a stepwise dilution with 2% human serum albumin and centrifugation performed either manually or using a blood cell processor (Cobe 2991). In vitro studies showed mean recoveries of 80.8% for BM nucleated cells and 73.9% for BM hematopoietic progenitors (CFU-GM). The corresponding recoveries for PBSC were 89.1 and 93.9%. After 4 h storage at +20 degrees C of the manipulated grafts, no significant loss of CFU-GM was observed. We conclude that the technique is simple and efficient for washing large numbers of hematopoietic stem cells. This method may avoid the clinical complications often arising with unwashed grafts.     

Analysis of circulating hematopoietic progenitor cells after peripheral blood stem cell transplantation

We investigated the kinetics of posttransplant circulating progenitor cells (PTCPC) in the early phase after autologous (auto-) and allogeneic (allo-) peripheral blood stem cell transplantation (PBSCT). We analyzed the number of myeloid progenitor cells (CFU-GM) per 10 ml of peripheral blood (PB) on days 0 (just prior to transplantation), 1 (12-15 hours after completion of first transplantation), 2, 3, 5, 7, 10, 14, 17, 21 and 28 (after auto-PBSCT), and also additionally on day 35 after allo-PBSCT. A standard methylcellulose colony assay was used for analysing the number of CFU-GGM and BFU-E on all of the days. In addition, high proliferative potential-colony forming cells (HPP-CFC) of the harvested PBSC from donors and day 1 PB from recipients were assayed in 5 allo-PBSCT patients. Furthermore, a proportion of CD38- cells among CD34+ cells in the harvested PBSC and day 1 PB was evaluated by two-color flow cytometric analysis in 5 allo-PBSCT patients. The number of CFU-GM on day 1 ranged from 7 to 119 per 10 ml PB after auto-PBSCT, and from 15 to 61 per 10 ml PB after allo-PBSCT. After these transient increases, PTCPC diminished rapidly. Then, PTCPC emerged again on day 7 after auto-PBSCT and on day 10 or 14 after allo-PBSCT along with neutrophil recovery. A proportion of HPP-CFC among myeloid colonies from day 1 PB of recipients was significantly higher than that from the harvested PBSC from donors (65.6 +/- 12.7% vs. 17.4 +/- 13.0%, respectively, n = 5, P = 0.0013). In addition, two-color flow cytometric analysis revealed that the proportion of CD34+CD38- cells was significantly higher in day 1 PB of recipients than in the harvested PBSC from donors (57.5 +/- 17.6% vs. 11.7 +/- 4.9%, n = 5, P = 0.005). These observations suggest that both primitive and committed transplanted myeloid progenitor cells may circulate in the very early period following PBSCT.     

Growth of primary human acute leukemia in severe combined immunodeficient mice

Seven populations of human leukaemic cells were implanted i.v. into sublethally irradiated severe combined immunodeficient (scid) mice. Growth of leukaemia was monitored by labelling murine peripheral blood (PB) cells with an anti-HLA monoclonal antibody and flow cytometric analysis. Two of the populations transplanted were fresh acute lymphoblastic leukaemia (ALL) bone marrow (BM) cells which both caused sustained proliferative growth in scid mice. Human cells accounted for up to a mean of 87% of the total nucleated cells (TNC) in the PB of these mice between weeks 12-15. One of these populations was passaged into fresh mice and frank leukaemia was again established. Three populations of cryopreserved acute myeloblastic leukaemia (AML) cells (2 obtained from PB and 1 from BM) and one population of cryopreserved biphenotypic acute leukaemia BM cells, only grew to a maximum of 4% within the 15 week period of the experiment. A cell population from an AML cell line (HL60), however, did engraft and proliferate resulting in a rapid deterioration of these mice between weeks 3-6 when the proportion of human cells accounted for 9% of the TNC in the PB.     

No difference in graft-versus-host disease, relapse, and survival comparing peripheral stem cells to bone marrow using unrelated donors

The clinical results in 107 patients receiving a peripheral blood stem cell (PBSC) graft mobilized by granulocyte colony-stimulating factor (G-CSF) from HLA-A, -B, and -DR-compatible unrelated donors were compared to 107 matched controls receiving unrelated bone marrow (BM) transplants. Engraftment was achieved in 94% of the patients in both groups. The PBSC graft contained significantly more nucleated cells, CD34(+), CD3(+), and CD56(+) cells (P <.001), and resulted in a significantly shorter time-to-neutrophil (15 versus 19 days) and platelet engraftment (20 versus 27 days), compared to the BM control group (P <.001). Probabilities of acute graft-versus-host disease (GVHD) grades II to IV were 35% and 32% (not significant [NS]) and of chronic GVHD 61% and 76% (NS) in the PBSC and BM groups, respectively. There was no difference between the 2 groups in bacteremia, cytomegalovirus reactivation or disease, and fungal infection. The 3-year transplant-related mortality (TRM) rates were 42% in the PBSC group and 31% in the BM controls (P =.7) and the survival rates were 46% and 51%, respectively. The probability of relapse was 25% and 31% in both groups (NS), resulting in disease-free survival rates of 43% in the PBSC group and 46% in the BM controls (NS). In the multivariate analysis, early disease, acute GVHD grade 0 to I, and presence of chronic GVHD were independent factors associated with a better disease-free survival in this study. PBSC from HLA-compatible unrelated donors can be used safely as an alternative to BM for stem cell transplantation.     

Human bone marrow lymphocytes: B and T cell precursors and subpopulations.

Characterization of the different lymphocyte populations in normal human bone marrow (BM) was attempted and compared to that in the peripheral blood (PB). B cells comprised 34% +/- 11% of lymphocytes in BM and 23% +/- 9% in PB. The majority of B cells carried IgM in BM and IgG in the PB. In the BM, cells carrying complement or Fc receptors were fewer than cells carrying Ig, but in the PB they were equal. T cells comprised 6% +/- 4% of lymphocytes in the BM and 62% +/- 7% in the PB. The majority of BM lymphocytes did not have B or T cell markers; these probably included B and T cell precursors. BM lymphocytes carrying surface Ig increased in a 7-day culture, whereas those of the PB decreased. Pokeweed mitogen induced Ig synthesis in B cells of PB but not those of BM. BM-T cells were more efficient than PB-T cells in inhibiting Ig synthesis of PB-B cells. These results indicate that the BM compartment contains immature B cells that are capable of partial differentiation and maturation in vitro. BM-B lymphocytes are probably not involved in the effector phase of the immune response since they are unable to synthesize Ig and because they carry few receptors for complement of Fc, BM-T lymphocytes are very few and have suppressor capability and therefore may play an essential role in regulation of Ig synthesis by B cells.     

Characterization of CD34+ subsets derived from bone marrow, umbilical cord blood and mobilized peripheral blood after stem cell factor and interleukin 3 stimulation

We characterized CD34+ cells purified from bone marrow (BM), mobilized peripheral blood (PB) and cord blood (CB) and we tried to establish correlations between the cell cycle kinetics of the CD34+CD38- and CD34+CD38+ subpopulations, their sensitivity to SCF and IL-3 and their expression of receptors for these two CSFs. At day 0, significantly fewer immature CD34+CD38- cells from CB and mobilized PB are in S + G2M phases of the cell cycle (respectively 2.0 +/- 0.4 and 0.9 +/- 0.3%) than their BM counterpart (5.6 +/- 1.2%). A 48-h incubation with SCF + IL-3 allows a significant increase in the percentage of cycling CD34+CD38- cells in CB (19.2 +/- 2.2%, P < 0.0002) and PB (14.1 +/- 5.5%, P < 0.05) while the proliferative potential of BM CD34+CD38- progenitors remains constant (8.6 +/- 1.0%, NS). CD123 (IL-3 receptor) expression is similar in the three sources of hematopoietic cells at day 0 and after 48-h culture. CD117 (SCF receptor) expression, although very heterogeneous according to the subpopulations and the sources of progenitors evaluated, seems not to correlate with the difference of progenitor cell sensitivity to SCF nor with their proliferative capacity. Considering the importance of the c-kit/SCF complex in the adhesion of stem cells to the microenvironment, several observations are relevant. The density of CD117 antigen expression (expressed in terms of mean equivalent soluble fluorescence, MESF) is significantly lower on fresh PB cells than on their BM (P < 0.017) and CB (P < 0.004) counterparts, particularly in the immature CD34+CD38- population (560 +/- 131, 2121 +/- 416 and 1192 +/- 129 MESF respectively); moreover, when PB and BM CD34+CD38- cells are stimulated for 48 h with SCF + IL-3, the CD117 expression decreases by 1.5- and 1.66-fold, respectively. This reduction could modify the functional capacities of ex vivo PB and BM manipulated immature progenitor cells.     

Adoption of long-term cultures to evaluate the cryoprotective potential of trehalose for freezing hematopoietic stem cells

Dimethylsulfoxide (DMSO), which is widely used as a cryoprotectant for hematopoietic stem cells (HSC), has considerable toxicity for both the thawed cells and the patient. The aim of this study was to evaluate the cryoprotective potential of trehalose in comparison to DMSO for human HSC. Human bone marrow (BM) and peripheral blood stem cells (PBSC) of volunteer donors were cryopreserved in the presence of different concentrations of trehalose with and without insulin, as well as with DMSO 10%. After thawing to 37 degrees C colony-forming unit (CFU) assays were performed. Long-term marrow-cultures (LTMC) were established and used for the detection of long-term culture-initiating cells (LTCIC). The total amount of CFUs detected was 104+/-134 (mean+/-s.d.) in DMSO-preserved cells and 179+/-34 in trehalose-protected cells. For LTMC the best feeder layer proved to be fresh human BM and the most useful concentration of trehalose was 0.5 M. Using these culture conditions we could detect after 5 weeks LTMC a total of 172+/-28 CFUs for trehalose-protected cells and 170+/-52 for DMSO-preserved cells. In conclusion, trehalose exerts a similar cryoprotective potential for hematopoietic progenitor and stem cells like DMSO and could possibly replace DMSO at least in part as cryoprotectant in the setting of hematopoietic cell transplantation.     

Hematopoietic stem cell transplantation for high-risk adult patients with severe aplastic anemia; reduction of graft failure by enhancing stem cell dose

BACKGROUND AND OBJECTIVES: The main causes of failure after allogeneic hematopoietic stem cell transplantation (HSCT) in patients with severe aplastic anemia (SAA) are graft-versus-host disease (GVHD), infection and graft failure, often exacerbated by large numbers of transfusions and prolonged disease duration before transplant. This study retrospectively analyzes the outcome and factors related to survival or graft failure in high-risk patients with SAA receiving HSCT in our institution. DESIGN AND METHODS: Between January 1995 and December 1999, 40 consecutive adult patients who were multi-transfused (more than 40 units of red blood cells +/- platelets) and/or had a 3 years or longer period prior to transplant were enrolled. Their median age was 27.5 years (range, 16 to 43) and 21 (52.5%) were women. All donors were human leukocyte antigen (HLA)-matched siblings. Before transplant, 29 patients (72.5%) received a course of antithymocyte globulin (ATG) and cyclosporin A (CsA). The median interval from diagnosis to transplant was 59 months (range, 2 to 216). The median number of transfusions was 115 units (range, 10 to 480). All patients received a conditioning regimen of cyclophosphamide, ATG, and procarbazine. Our patients received either bone marrow (BM) alone (n=20) or BM+peripheral blood stem cells (PBSC) (n=20) as a stem cell source. T-cells of PBSC were depleted using the CD34 enrichment method. GVHD prophylaxis consisted of CsA and short-term methotrexate. RESULTS: In the BM+PBSC group, neutrophil recovery to 0.5 x 10(9)/L and platelet recovery to 20 x 10(9)/L were achieved more rapidly than in the BM group (p=0.005 and 0.039, respectively). The incidences of graft failure, grade II to IV acute GVHD, and chronic GVHD were 22.5%, 12.8% and 23.1%, respectively. Graft failure occurred in 2 of 20 patients (10%) receiving BM+PBSC and in 7 of 20 (35%) receiving BM alone (p=0.069). Seven of 9 patients who had graft failure received a booster treatment and recovered normal marrow function. GVHD incidence was comparable between the BM+PBSC and BM groups. Six patients (15%) died from graft failure (n=2), interstitial pneumonia (n=2), cyclophosphamide-induced heart failure (n=1), and chronic GVHD followed by pneumonia (n=1). The Kaplan-Meier estimate of survival was 83.7% with a median follow-up duration of 40.5 months (range 8-67). In multivariate analysis only chronic GVHD adversely influenced survival (p=0.042). INTERPRETATION AND CONCLUSIONS: These results suggest that HSCT is an effective treatment for multi-transfused SAA patients with prolonged disease duration. It is highly possible that the infusion of a large number of stem cells leads to a reduction of graft failure and a faster speed of engraftment. Booster treatment is successful in achieving engraftment in patients with graft failure.     

Immune reconstitution after purified autologous and allogeneic blood stem cell transplantation compared with unmanipulated bone marrow transplantation in children

Immune reconstitution is critical for the long-term success of haematopoietic stem cell transplantation (HSCT). We prospectively analysed immune reconstitution parameters after transplantation of autologous (group 1; n = 10) and allogeneic (group 2; n = 12) highly purified CD34+ peripheral blood stem cells (PBSC) and unmanipulated allogeneic bone marrow (BM) (group 3; n = 9) in children. Median follow-up after HSCT was 56 (group 1), 61 (group 2), and 40.5 months (group 3). Median CD34-cell dose transplanted in the three groups was 9.4 x 10(6)/kg, 20.3 x 10(6)/kg, and 4.25 x 10(6)/kg recipient's body weight (BW) respectively. Complete haematopoietic engraftment was seen in all patients without any significant differences between the three groups. T-cell reconstitution at 6 months was significantly delayed in autologous peripheral blood stem cell transplantation (PBSCT) compared with allogeneic BM transplantation (P < 0.028) and allogeneic PBSCT (P < 0.034). At 3 months after transplantation numbers of CD56+/3- natural killer cells were higher in the allogeneic PBSC group (P < 0.01) compared with the BM group. The numbers of proven bacterial and viral infections were equally distributed between the three groups. In conclusion, recipients of allogeneic highly purified CD34+ PBSC or unmanipulated BM have higher lymphocyte subset counts at 6 months after transplantation than recipients of autologous CD34-selected PBSC. Infection rates and outcome, however, were not significantly different.     

Unrelated donor peripheral blood stem cell transplants incorporating pre-transplant in-vivo alemtuzumab are not associated with any increased risk of significant acute or chronic graft-versus-host disease

There is little information published comparing peripheral blood stem cells (PBSC) with bone marrow (BM) as the stem cell source in the long-term outcome in recipients of T-cell depleted (TCD) unrelated donor (UD) transplants. We present retrospective outcome data on 306 recipients of myeloablative, human leucocyte antigen-matched UD allografts using pre-transplant in-vivo Alemtuzumab. Transplants were performed between 2000 and 2007 for chronic myeloid leukaemia in first chronic phase and acute leukaemia in first or second complete remission; 184 patients received BM and 122 PBSC. The median age was 28·9 years (<1-58) and the median follow-up was 48 months. Overall survival at 8 years was 53%. The incidence of acute graft-versus-host disease (GvHD) was significantly higher in PBSC (65%) than BM recipients (49%; P=0·012). This represented only grade 1 GvHD with no difference in grade II-IV aGvHD (BM 23% PBSC 24%). The incidence of chronic GvHD, either overall (BM 47%, PBSC 49%) or extensive (BM 15%, PBSC 13%) was not increased with PBSC. The incidence of relapse, non-relapse mortality and survival were not significantly different. Whilst accepting the limitations of retrospective analyses, we suggest the increased risk of GvHD in recipients of PBSC in T-replete transplants is offset by in-vivo Alemtuzumab, and that either stem cell source can be used with good outcomes in this setting.