Poor immune reconstitution after four or five major HLA antigens mismatched T cell-depleted allogeneic and autologous stem cell transplantation

Two adults with primary liver cancer underwent liver transplantation from 5/6 and 4/6 major HLA-antigen mismatched unrelated donors. They were then conditioned with 4 x 2 Gy of total lymphoid irradiation, 120 mg/kg cyclophosphamide, 7.5 Gy total body irradiation and anti-T cell antibodies. Thereafter, the patients received T cell-depleted autologous: unrelated mismatched bone marrow in a proportion of 0.5:3.0 and 0.35:1.1 x 10(6) CD34+ cells/kg, respectively. After allogeneic stem cell transplantation (ASCT), both became mixed chimeras, as determined with polymerase chain reaction amplification of variable number tandem repeats from DNA obtained from CD3+, CD19+ and CD45+ magnetic bead-separated cells. Due to a reduction in donor T cells, the first patient was given 10(5) donor T cells/kg and became a complete donor chimera within 3 months. The second patient rejected all donor cells within 1 month after ASCT. Leucocytes normalized in both patients within 1 month. CD8+ cells normalized after 4 and 2 months in the two patients, respectively. However, CD4+, CD56+ and CD19+ cells remained low, except for a transient increase in patient 2. Lymphocyte responses to mitogens were negative in patient 1 from 1 to 5 months after ASCT. This patient also showed an oligoclonal pattern of the B cell repertoire, performed by CDR3 spectratyping. Epstein-Barr virus DNA in lymphocytes increased by 4-5 log in both patients. Prior to ASCT, recipients and donors were mutually reactive in mixed lymphocyte cultures (MLC). In the first patient, who became a complete donor chimera, the chimera cells showed no response to recipient or donor, but a positive response to third party. In the other patient, recipient cells reacted vigorously against donor lymphocytes at the time of rejection. Both patients suffered from overwhelming bacterial, fungal and viral infections, and died of pneumonia 5 and 3 months after ASCT, respectively. To conclude, with a major HLA-mismatch barrier, stable mixed chimerism seems difficult to achieve. The first patient became a full donor chimera and the second one rejected the graft. Both suffered from immune incompetence.     

Establishing a platform for immunotherapy: clinical outcome and study of immune reconstitution after high-dose chemotherapy with progenitor cell support in breast cancer patients.

Tumor vaccine after high-dose chemotherapy (HDC) and autologous stem cell transplantation (ASCT) aims at directing immune recovery toward tumor responses after optimizing minimal residual disease. We have characterized T-cell recovery and tumor response after a regimen devised as a platform for such immunotherapy. One hundred patients with high-risk or metastatic breast cancer received 3 to 7 cycles of paclitaxel and cyclophosphamide (overall response rate, 78%) and then HDC with melphalan and etoposide. Seventy-one patients received HDC and ASCT (no mortality at 100 days). At 24 months after transplantation, progression-free and overall survival probabilities for patients with stage IIIA, IIIB, and IV disease were 82%, 81%, and 42% and 100%, 94%, and 68%, respectively. The median progression-free and overall survivals from entry on study for stage IV patients were 15.3 and 38.1 months, respectively. CD3 + , CD8 + , and CD4 + cells were severely depleted after ASCT. Although total CD8 + T-cell numbers approached the normal range by 3 months, most of these cells were CD28 - . Naive CD45RA + CD4 + T cells approached the normal range only 18 months after ASCT and only in younger patients. The described observations provide the basis for devising a strategy for cancer vaccine administration after ASCT. Incorporating immune reconstitution enhancement after ASCT may be advantageous.     

Treatment of Rheumatoid Arthritis with Single Dose or Weekly Pulses of Chimaeric Anti-CD4 Monoclonal Antibody

The aetiology of rheumatoid arthritis is unknown but CD4+ T cells are known to be involved in its pathogenesis. Because of this, anti-CD4 monoclonal antibody has been used in open studies with clinical benefit in up to 60% of patients. We have used a chimaeric anti-CD4 monoclonal antibody (cM-T412, Centocor) in a randomized, double-blinded, placebo controlled trial as treatment for rheumatoid arthritis. Nine patients with active rheumatoid arthritis resistant to traditional disease-modifying drugs were recruited. Four received an intravenous 50 mg bolus of antibody, and three received 50 mg weekly for four consecutive weeks. Two patients received placebo. Despite a marked reduction (P less than 0.001) in peripheral blood CD4+ lymphocytes, there was no significant clinical improvement in any of these patients. The decrease in CD4+ lymphocyte number lasted one week after a single 50 mg dose of cM-T412 but was more prolonged in the patients who received four infusions. CD8+ T cells, CD16+ cytotoxic cells and CD14+ monocytes showed only a transient reduction. It may be concluded that the therapeutic efficacy of anti-CD4 therapy is not directly related to CD4+ T-cell lymphopenia.     

Safe and efficacious allogeneic bone marrow transplantation for nonmalignant disorders using partial T cell depletion and no posttransplantation graft-versus-host-disease prophylaxis.

In an attempt to abrogate the deleterious effects of graft-versus-host disease (GVHD), allogeneic transplantation for nonmalignant diseases was performed using high-dose CD34-cell infusion, partial T cell depletion, and no posttransplantation GVHD prophylaxis. Between 1998 and 2004, 16 patients with matched related donors were treated. Median age was 1.5 years (range, 5 months-18 years). The conditioning regimen consisted of busulphan 16 mg/kg, cyclophosphamide 200 mg/kg, antithymocyte globulin (ATG) 25 mg/kg, and fludarabine 200 mg/m(2). No GVHD prophylaxis was given. High doses of CD34 cells, positively selected by immunomagnetic beads, were infused at a median dose of 10.7 x 10(6) CD34/kg (range, 7.4-50 x 10(6)). A total of 1 x 10(5)/kg T cells were given. All patients engrafted, with no graft rejections. All were alive and well at a median of 37 months posttransplantation (range, 18-89 months). Only 1 patient developed chronic GVHD. No episodes of severe infection occurred during or after transplantation. Immunologic reconstitution with CD3/CD4 T cells > 200/microL was observed at a median of 117 days and that with naive T cells (CD4/CD45RA) at a median of 188 days posttransplantation. Our findings suggest that allogeneic transplantation from a matched family donor for nonmalignant disorders can be successfully performed using high doses of CD34 cells, moderate T cell depletion, and no posttransplantation immunosuppression.     

Transplantation of highly purified CD34+Thy-1+ hematopoietic stem cells in patients with recurrent indolent non-Hodgkin's lymphoma.

PURPOSE: To evaluate the results of high-dose chemotherapy and transplantation of highly purified "mobilized" peripheral blood CD34+Thy-1+ hematopoietic stem cells (HSCs) in patients with recurrent indolent non-Hodgkin's lymphoma (NHL) or mantle cell lymphoma (MCL). PATIENTS AND METHODS: Twenty-six patients with recurrent indolent NHL or MCL were mobilized witheither granulocyte colony-stimulating factor (G-CSF) alone or cyclophosphamide plus G-CSF. Apheresis was performed, and the product was purified using the Isolex immunomagnetic positive CD34+ cell selection device initially and subsequent high-speed flow-cytometric cell sorting for the final purification of CD34+Thy-1+ HSCs. The patients received high-dose chemotherapy with BEAC (carmustine, etoposide, cytarabine, and cyclophosphamide) followed by transplantation with the purified HSCs in 2 dose cohorts (cohort 1: > or =5 x 10(5) viable and pure HSC/kg; cohort 2: > or =3 x 10(5) HSC/kg). RESULTS: We attempted to mobilize 26 patients with G-CSF alone. Six patients did not collect adequate cells with G-CSF alone; subsequent mobilization with cyclophosphamide plus G-CSF was attempted, but adequate CD34+Thy-1+ HSCs could not be collected on these 6 patients. Twenty patients underwent transplantation with the BEAC transplantation regimen followed by purified HSCs. Patients in cohort 1 engrafted at a median of day 12 to an absolute neutrophil count (ANC) >500/microL, a median of day 19 for platelet transfusion independence, and a median of day 20 for red blood cell transfusion independence. Patients in cohort 2 engrafted at a median of day 12 to an ANC >500/microL, a median of day 12 for platelet transfusion independence, and a median of day 12 for red blood cell transfusion independence. Fourteen of the 20 patients had significant infections reported at some point posttransplantation, including influenza, respiratory syncytial virus, pneumonitis, and Pneumocystis carinii pneumonia. With a median follow-up of 38 months, 8 of the 20 patients have had progressive lymphoma and 5 patients have died. The 3-year event-free survival is 55%, and overall survival is 78%. CONCLUSIONS: CD34+Thy-1+ HSCs can be collected successfully from most lymphoma patients mobilized with G-CSF alone. The engraftment and disease outcomes in the patients in this small pilot study using these cells do not appear to be different from the outcomes of similar patients cited in the literature. However, the short- and long-term risks of infection were a concern in this patient population.     

Allogeneic stem cell transplantation with peripheral blood stem cells mobilized by pegylated G-CSF.

Mobilization of stem cells with pegylated granulocyte colony-stimulating factor (peg-G-CSF) modulates donor T- and natural killer T-cell (NKT-cell) functions, thus separating graft-versus-host from graft-versus-leukemia disease in animal models. We report a phase I/II study that analyzed the feasibility of mobilizing stem cells from normal donors with peg-G-CSF and the ability of these cells to restore hematopoiesis in allogeneic transplant recipients after myeloablative conditioning. Administration of 6 mg of peg-G-CSF resulted in suboptimal stem cell mobilization, with a peak peripheral blood CD34+ count of 29+/-5/microL. Apheresis 4 days after peg-G-CSF yielded 2.7+/-.4x10(6) CD34+ cells/kg recipient weight, and all donors required a second collection on day 5 to yield a total of 4.2+/-.5x10(6) CD34+ cells/kg recipient weight. After escalation of the dose to 12 mg, the peak CD34+ count was 99+/-11/microL and 12 of 13 donors collected sufficient stem cells for transplantation in a single apheresis (8.9+/-1.4x10(6) CD34+ cells/kg recipient weight). Late transient increases in serum hepatic transaminases were noted, but other side effects (predominantly bone pain) were otherwise similar to those seen in donors mobilized with standard G-CSF. Median neutrophil and platelet engraftments occurred on days 18 and 14, respectively, after transplantation and were identical to those seen with in recipients of grafts mobilized with standard G-CSF. With a median follow-up of 357 days, the incidence of grade II-IV acute graft-versus-host disease was 50% and there have been no relapses to date. Mobilization of stem cells with peg-G-CSF in normal donors is feasible and 12 mg results in mobilization characteristics similar to those of standard G-CSF.     

High CD34+ cell dose promotes faster platelet recovery after autologous stem cell transplantation for acute myeloid leukemia.

We studied platelet engraftment in 58 patients with acute myeloid leukemia in first remission treated with autologous stem cell transplantation (ASCT) to determine whether CD34+ cell doses >10 x 10(6)/kg were associated with faster platelet engraftment. We compared engraftment rates in patients receiving CD34+ doses between 5 and 10 x 10(6)/kg (standard-dose ASCT) with those receiving doses > or =10 x 10(6)/kg (high-dose [HD] ASCT). We also studied neutrophil engraftment rates and platelet and red blood cell transfusion requirements. In multivariate adjusted models, the rate of platelet recovery to > or =20,000/microL was 4-fold greater among subjects who received HD-ASCT (hazard ratio [HR], 4.1; confidence interval [CI], 1.8-9.2; P =.001), with median recovery times of 14 versus 28 days. The rate of platelet recovery to > or =50,000/microL was 2-fold greater (HR, 2.1; CI, 1.3-5.9; P =.01), with median recovery times of 19 versus 46 days. Faster platelet recovery resulted in the need for fewer platelet transfusions among the subjects who received HD-ASCT (mean transfusions, 3.7 versus 9.8; P =.005). Although not statistically significant, neutrophil recovery data in the adjusted model suggested a similar effect in the HD-ASCT group, with faster engraftment times at absolute neutrophil counts >500/microL (median, 9.2 versus 12 days; HR, 1.6; CI, 0.69-3.5; P =.29) and absolute neutrophil counts >1000/microL (median, 9.5 versus 12 days; HR, 1.3; CI, 0.56-2.8; P =.58). Subjects who received HD-ASCT required fewer red blood cell transfusions (4.0 versus 9.8 units; P =.01). Our findings suggest that CD34+ cell doses >10 x 10(6)/kg CD34+ result in faster engraftment and fewer red blood cell and platelet transfusions.     

Use of thrombopoietin in combination with chemotherapy and granulocyte colony-stimulating factor for peripheral blood progenitor cell mobilization.

This phase I/II dose-escalation study examined the safety and efficacy of recombinant human thrombopoietin (rhTPO) and granulocyte colony-stimulating factor (G-CSF) for postchemotherapy mobilization of peripheral blood progenitor cells (PBPCs) in patients with advanced breast cancer. Patients received cyclophosphamide, etoposide, and cisplatin (CVP) followed by G-CSF (6 microg/kg twice a day) and rhTPO (0.6, 1.2, 2.4, or 3.6 microg/kg as a single dose on day 5 or as 3 doses on days 5, 7, and 9 after chemotherapy). PBPCs were collected by daily leukapheresis when the postnadir white blood cell count reached > or = 2 x 10(9)/L; leukapheresis was continued until acquisition of a target dose of > or = 5 x 10(6) CD34+ cells/kg. Mobilized PBPCs were transplanted into patients after additional high-dose chemotherapy with cyclophosphamide, carmustine, and thiotepa (CBT). Comparisons were made with contemporaneously treated, nonrandomized, control patients who received the same chemotherapy regimens and G-CSF support but who did not receive rhTPO. Of 32 evaluable patients receiving rhTPO and G-CSF after CVP, 91% required only 1 leukapheresis to achieve a target PBPC graft; by contrast, only 69% of 36 of the control patients achieved the target graft with just 1 leukapheresis (P = .026). A median of 26.7 x 10(6) CD34 cells/kg per leukapheresis was obtained from the rhTPO-treated patients compared with 11.5 x 10(6) cells/kg per leukapheresis from the controls (P = .09). Higher rhTPO doses appeared to yield more CD34+ cells. When PBPCs were infused after high-dose CBT chemotherapy, the median times to return of an absolute neutrophil count of 0.5 x 10(9)/L and a platelet count of 20 x 10(9)/L were 15 and 16 days, respectively; these values did not differ from those in the control group (15 days for both neutrophil and platelets). No patient developed anti-TPO antibodies. These results indicate that rhTPO safely and effectively augments the number of PBPCs mobilized with chemotherapy and G-CSF and can reduce the required number of leukaphereses. Further studies are also warranted in patients who are likely to experience suboptimal PBPC mobilization when treated with currently available techniques.     

Infused CD34+ cell dose predicts long-term survival in acute myelogenous leukemia patients who received allogeneic bone marrow transplantation from matched sibling donors in first complete remission.

Allogeneic stem cell transplantation (ASCT) has improved the outcome of acute myelogenous leukemia (AML). To further improve the treatment outcome of ASCT in AML, finding a modifiable prognostic factor is mandatory. We evaluated the effect of CD34(+) cell dose on survival in allogeneic bone marrow transplantation (BMT) from HLA-matched sibling donors for AML patients in first complete remission (CR1). The 99 patients included in our analysis were classified into high CD34(+) cell dose group (CD34(+) cells > or = 2.5 x 10(6)/kg) and low CD34(+) cell dose group (CD34(+) cells < 2.5 x 10(6)/kg). The high CD34(+) cell dose patients had better overall survival (5-year overall survival rate, 75% +/- 6% vs 52% +/- 9%; P = .01) and leukemia-free survival (5-year leukemia-free survival rate, 70% +/- 6% vs 44% +/- 9%; P = .04). CD34(+) cell dose was the only independent prognostic factor in overall survival and leukemia-free survival. The high CD34(+) cell dose group had a lower relapse incidence with a borderline statistical significance (5-year relapse rate, 27% +/- 6% vs 50% +/- 10%; P = .09). There were no differences in the engraftment of neutrophil and platelet, grade II-IV acute graft-versus-host disease (GVHD), extensive-stage chronic GVHD, and transplant-related mortality between the high and low CD34(+) cell dose groups. We confirmed that high CD34(+) cell dose favorably affects the outcomes in allogeneic BMT for AML. The effort to attain a high CD34(+) cell dose should be pursued during bone marrow harvest in allogeneic BMT for AML in CR1.     

Matched-pair analysis of hematopoietic progenitor cell mobilization using G-CSF vs. cyclophosphamide, etoposide, and G-CSF: enhanced CD34+ cell collections are not necessarily cost-effective.

Using matched-pair analysis, we compared two popular methods of stem cell mobilization in 24 advanced-stage breast cancer patients who underwent two consecutive mobilizing procedures as part of a tandem transplant protocol. For the first cycle, 10 microg/kg/day granulocyte colony-stimulating factor (G-CSF) was given and apheresis commenced on day 4 and continued for < or =5 days (median 3 days). One week after the first cycle of apheresis, 4000 mg/m2 cyclophosphamide, 400 mg/m2 etoposide, and 10 microg/kg G-CSF were administered for < or =16 days (cycle 2). Apheresis was initiated when the white blood cell (WBC) count exceeded 5000 cells/microL and continued for < or =5 days (median 3 days). Mean values of peripheral blood WBC (31,700+/-3200 vs. 30,700+/-3300/microL) were not significantly different between cycles 1 and 2. Mean number of mononuclear cells (MNC) collected per day was slightly greater with G-CSF mobilization than with the combination of chemotherapy and G-CSF (2.5+/-0.21x10(8) vs. 1.8+/-0.19x10(8) cells/kg). Mean daily CD34+ cell yield, however, was nearly six times higher (12.9+/-4.4 vs. 2.2+/-0.5x10(6)/kg; p = 0.01) with chemotherapy plus G-CSF. With G-CSF alone, 13% of aphereses reached the target dose of 5x10(6) CD34+ cells/kg in one collection vs. 57% with chemotherapy plus G-CSF. Transfusions of red blood cells or platelets were necessary in 18 of 24 patients in cycle 2. Three patients were hospitalized with fever for a median of 3 days after cycle 2. No patients received transfusions or required hospitalization during mobilization with G-CSF alone. Resource utilization (cost of drugs, aphereses, cryopreservation, transfusions, hospitalization) was calculated comparing the median number of collections to obtain a target CD34+ cell dose of 5x10(6) cells/kg: four using G-CSF vs. one using the combination in this data set. Resources for G-CSF mobilization cost $7326 vs. $8693 for the combination, even though more apheresis procedures were performed using G-CSF mobilization. The cost of chemotherapy administration, more doses of G-CSF, transfusions, and hospitalizations caused cyclophosphamide, etoposide, and G-CSF to be more expensive than G-CSF alone. A less toxic and less expensive treatment than cyclophosphamide, etoposide, and G-CSF is needed to be more cost-effective than G-CSF alone for peripheral blood progenitor cell mobilization.     

Tandem autologous stem cell transplantation for patients with primary refractory or poor risk recurrent Hodgkin lymphoma.

Although autologous stem cell transplantation (ASCT) for patients with relapsed/refractory Hodgkin lymphoma (HL) appears to offer a survival advantage over conventional therapy, only approximately 25% to 35% of patients with primary progressive or poor-risk recurrent HL can achieve durable remission after ASCT, with disease progressive after transplant accounting for most of the treatment failures. We conducted a pilot study to evaluate the toxicities and efficacy of a tandem transplant approach in this subgroup of patients. Between April 1998 and March 2000, 46 patients were enrolled in the study. Eligibility criteria: primary progressive (n = 28) or recurrent HL (n = 18) with at least 1 of the following poor prognostic factors: first complete remission (CR) <12 months (n = 15) or extra-nodal disease (n = 4) or B symptoms at relapse (n = 4). The first cycle consisted of melphalan (150 mg/m(2)) alone. The second cycle consisted of fractionated total body irradiation (FTBI) 1200 cGy or BCNU (450 mg/m(2)) in combination with etoposide (60 mg/kg) and cyclophosphamide (100 mg/kg). Of the 46 patients, 5 (11%) did not receive the planned tandem transplants because of inadequate stem cell collection for 2 ASCT. After a median of 64 days (25-105), 41 patients received the second ASCT. With a median follow-up of 5.3 years (1.6-8.1), the 5-year estimate of overall survival, progression-free survival, and freedom from progression were 54% (95% confidence interval [CI] 40%-69%), 49% (95% CI, 34%-63%), and 55% (95%CI, 40%-70%), respectively. Our mature results from this study suggest that in patients with primary progressive or poor risk recurrent HL, this tandem ASCT program is effective and well tolerated and compares favorably with the conventional single transplant.     

Efficacy of CD34+ stem cell dose in patients undergoing allogeneic peripheral blood stem cell transplantation after total body irradiation.

We estimated the effect of CD34(+) stem cell dose during peripheral blood stem cell transplantation (PBSCT) in predicting mortality after total body irradiation (TBI). Between 1997 and 2004, 146 consecutive patients with hematologic malignancies received fractionated TBI (12-13.6 Gy) in 8 fractions over 4 days before undergoing PBSCT; 61 patients received TBI with reduced radiation dose to the lung (6-9 Gy). The number of CD34(+) cells transplanted was recorded for all patients. A cubic spline representation for CD34(+) dose within a Cox proportional hazards model was used to model the relationship between the CD34(+) dose and mortality. Median follow-up was 44 months (range, 12-90 months). The CD34(+) cell dose ranged from 2.45 to 15.90 x 10(6) cells/kg (median, 5.15 x 10(6) cells/kg). Risk of mortality decreased with CD34(+) doses between 4-8 x 10(6) cells/kg and then began to increase. For all patients, CD34(+) doses of 5.1-12.9 x 10(6)/kg resulted in at least a doubling of median survival associated with the lowest CD34(+) value. In patients treated with lung dose reduction, a similar range of CD34(+) dose (4.3-10.2 x 10(6) cells/kg) produced at least a 5-fold improvement from the survival associated with the lowest CD34(+) dose; however, the relationship between CD34(+) dose and mortality was not statistically different when analyzed by lung dose reduction. A method for assessing risk of mortality by CD34(+) dose as a continuous variable is presented. Risk of mortality decreased with CD34(+) doses between 4-8 x 10(6) cells/kg and then began to increase.     

Effective purging of autologous hematopoietic stem cells using anti-B-cell monoclonal antibody-coated high-density microparticles prior to high-dose therapy for patients with non-Hodgkin's lymphoma.

Contamination of hematopoietic stem cells (HSCs) with tumor cells has been associated with increased incidence of relapse in patients with non-Hodgkin's lymphoma following autologous HSC transplantation. Effective purging of tumor cells may improve the results of HSC transplantation, but current methods of purging are technically difficult to perform with large numbers of cells and do not consistently remove all detectable cells. We report a pilot clinical trial in which 10 patients with relapsed B-cell non-Hodgkin's lymphoma received high-dose chemotherapy followed by infusion of autologous HSCs depleted of B-cells by high-density microparticles (HDM) coated with anti-CD19 and anti-CD20 monoclonal antibodies (BCell-HDM). HSCs were mobilized with cyclophosphamide and granulocyte colony-stimulating factor. In 6 of the 10 patients, B-cells were detectable by immunocytochemical analysis of the apheresis products prior to treatment. Following treatment with the BCell-HDM, no B-cells were detected in the products from 5 of these patients, a result representing a median depletion of >2.2 logs (range, >0.4 to >5.1 logs). The median recovery of nontarget cells postdepletion was 73% for CD34 cells and 78% for CD3+ cells. All patients received high-dose cyclophosphamide, BCNU (carmustine), and etoposide prior to reinfusion of their B-cell-depleted autologous HSCs. The median number of CD34+ cells cryopreserved was 3.6 x 10(6) cells/kg (range, 2.2-10.1 x 10(6) cells/kg). Engraftment was rapid in all cases, with a median time to achieve an absolute neutrophil count of 0.5 x 10(9)/L of 10 days (range, 8-11 days). The median time to achieve a platelet count of 20 x 10(9)/L unsupported by platelet transfusion was 11.5 days (range, 8-17 days). This nonmagnetic negative-depletion technology is simple, rapid, and effective in depleting target cells to undetectable levels, with excellent recovery of nontarget cells.     

Transplantation of highly purified CD34+Thy-1+ hematopoietic stem cells in patients with metastatic breast cancer.

We report here the transplantation of extensively purified "mobilized" peripheral blood CD34Thy-1 hematopoietic stem cells from 22 patients with recurrent or metastatic breast cancer. Patients were mobilized with either high-dose granulocyte colony-stimulating factor (G-CSF) alone or cyclophosphamide plus G-CSE Median purity of the stem cell product at cryopreservation was 95.3% (range, 91.1%-98.3%), and viability was 98.6% (range, 96.5%-100%). After high-dose chemotherapy with carmustine, cisplatin, and cyclophosphamide, CD34+Thy-1 cells at a median dose of 11.3 x 10(5) per kilogram (range, 4.7-163 x 10(5) per kilogram) were infused. No infusion-related toxicity was observed. Neutrophil recovery was prompt, with median absolute neutrophil count >500/microL by day 10 (range, 8-15 days) and >1000/microL by day 11 (range, 8-17 days). Median platelet recovery (>20,000/microL) was observed by day 14 (range, 9-42 days) and >50,000/microL by day 17 (range, 11-49 days). Tumor cell depletion below the limits of detection of a sensitive immunofluorescence-based assay was accomplished in all patients who had detectable tumor cells in apheresis products before processing. Although CD4+ T-cell reconstitution was slow, no unusual infections were observed. Neither early nor late graft failure was observed, and no patient required infusion of unmanipulated backup cells. At a median follow-up of approximately 1.4 years and a maximum follow-up of 2.5 years, 16 of the 22 patients remain alive, with 9 free of disease progression, and have stable blood counts. In summary, highly purified CD34+Thy-1+ cells used as the sole source of the hematopoietic graft result in rapid and sustained hematopoietic engraftment.     

Systematic review of randomized controlled trials of hematopoietic stem cell mobilization strategies for autologous transplantation for hematologic malignancies

Collection of adequate hematopoietic stem cells (HSCs) is necessary for successful autologous transplantation; however, a proportion of patients fail to collect the minimum number of cells required. We summarized the efficacy and safety of HSC mobilization strategies. We performed a systematic review of randomized controlled trials comparing HSC mobilization strategies before autologous transplantation for hematologic malignancies. The primary outcome was CD34+ cell yield. Secondary outcomes included number of aphereses, proportion of failures, rate of count recovery, and adverse events. We identified 28 articles within 3 broad strategies. Using a cyclophosphamide with growth factor strategy (10 articles), CD34+ cell yield is improved by addition of molgramostim to cyclophosphamide (1.4 vs 0.5 × 10(6)/kg; P = .0165), addition of cyclophosphamide to filgrastim (7.2 vs 2.5 × 10(6)/kg; P = .004), and addition of ancestim to cyclophosphamide and filgrastim (12.4 vs 8.3 × 10(6)/kg; P = .007). Within a growth factor-based strategy (6 articles), addition of plerixafor improves CD34+ cell yield over filgrastim alone in multiple myeloma (MM; 11.0 vs 6.2 × 10(6)/kg; P?< .001) and non-Hodgkin lymphoma (5.69 vs 1.98 × 10(6)/kg; P < .01). With combination or noncyclophosphamide-based chemotherapy (12 articles), higher-dose filgrastim (8.2 vs 4.7 × 10(6)/kg for 16 vs 8/mcg/kg daily of filgrastim, respectively; P < .0001) and addition of rituximab to etoposide and filgrastim (9.9 vs 5.6 × 10(6)/kg; P = .021) improve CD34+ cell yield. Growth factor alone after chemotherapy, ancestim, or plerixafor provide adequate autologous HSC grafts for the majority of patients. Although some strategies result in higher CD34+ cell yield, this potentially comes at the expense of increased toxicity. As all strategies are reasonable, programmatic, and patient-specific considerations must inform the approach to autologous graft mobilization.     

The possible cost effectiveness of peripheral blood stem cell mobilization with cyclophosphamide and the late addition of G-CSF

The purpose of this study was to develop a cost-effective protocol for the mobilization of peripheral blood stem cells (PBSC) in patients with malignancy. Thirty consecutive patients were randomized to mobilize PBSC with the late addition of a standard 250 microg dose of G-CSF (Neutrogen) from day 8 or early addition of the same dose of G-CSF from day 2, following cyclophosphamide (CY) 4 g/m2. The median yield of CD34+ cells from evaluated patients was 7.87 x 10(6)/kg (range, 2.06-27.25), collected in a median of four apheresis (range, 2-9). Target CD34 + cell doses > or = 2.0 x 10(6)/kg were achieved in all patients able to be evaluated. There were no statistically significant differences in CD34+ cell yields or toxicities. Overall engraftment occurred with median days to neutrophils > or = 0.5 x 10(9)/L or platelets > 20 x 10(9)/L of 11 and 17 days, respectively. However, the duration of G-CSF administration was markedly shorter in the late use of G-CSF group than in the early use of G-CSF group, with a median of 9 days compared with 15 days (p<0.001). PBSC harvesting after priming with CY plus delayed use of G-CSF made it a safe and cost-effective procedure.     

Large volume leukapheresis for collecting hemopoietic progenitors: role of CD 34+ precount in predicting successful collection.

In this work we evaluated the efficacy of stem cell collection with Large Volume Procedures. (LVP), and analysed the importance of the CD34+ cell precount in promoting the collection of a sufficient number of CD34+ cells for transplantation, using the Univariate Logistic Regression analysis. Eighty-nine leukapheresis were performed in 49 patients with hematological malignancies and solid tumors, mobilized with chemotherapy plus Granulocyte Colony Stimulating Factor (G-CSF). For each procedure 15.8 liters of blood were processed. The median value of Nucleated Cells (NC) and CD34+ cells precount was respectively 8.29 x 10(9)/ml (range 1.13/45.4) and 43.08 x 103/ml (range 1.06/795.2). Results show the capability of LVP to collect large quantities of hemopoietic progenitors with a median CD34+ cell total yield of 215.02 x 10(6) (range 5.03/2210). The yields per patients' body weight were: CD34+ cells 3.23 x 10(6)/kg (range 0.081/41.58). The regression analysis between blood cell precounts and collection yields gave the following correlations: the CD34+ cell precount correlates with CD34+ yield (r = 0.78 p < 0.00) and with CD34+ cell yield/kg (r = 0.76 p < 0.00). The number of CD34+ cells processed correlated with the number of CD34+ cells collected/kg (r = 0.83 p < 0.000). To investigate the importance of CD 34+ cell precount in promoting CD34+ cell yields > or =2.5 x 10(6)/kg we performed a Univariate Logistic Regression analysis that showed in our patients a probability of collecting > or =2.5 x 10(6) CD34+/kg that rose from 0.6 to 0.95 for CD 34+ precounts that oscillated from 30 to 40 x 10(3) CD34+ cells/ml, respectively. The Univariate Logistic Regression gave a probability of collecting > or =2.5 x 10(6) CD34+ cells/kg that oscillated between 0.64/0.98 for values of CD34+ cells processed from 6 x 10(6)/kg to 8 x 10(6)/kg, p < 0.000. Sixty-three percent of patients reached the target dose of 2.5 x 10(6) CD34+ cells/kg with only one LVP. Until now 12 patients have been transplanted and all have had a prompt and complete lasting recovery. These results confirm the efficacy of LVP in harvesting hemopoietic progenitors and their ability in reconstituting hemopoiesis of transplanted patients, enabling the estimation of CD34+ precounts and CD34+ cells processed values, highly predictive for the collection of > or =2.5 x 10(6) CD34+ cells/kg. Furthermore, the Logistic Model suggests that the best strategy to plan a successful CD34+ cell collection procedure is to identify for each patient the amount of CD34+ cells/kg to be processed rather than the fixed processing of 3/5 blood volumes in all patients.     

自体外周血干细胞动员和采集并联合化疗方案治疗儿童神经母细胞瘤及原始神经外胚层肿瘤35例

背景：自体外周血干细胞移植是目前治疗恶性实体瘤的重要方法之一,干细胞动员与采集是决定造血重建的重要因素。 目的：主要评价环磷酰胺,吡柔比星,长春新碱动员方案对儿童神经母细胞瘤及原始神经外胚层肿瘤自体外周血造血干细胞移植动员采集的临床效果。 方法：对35例患儿,确诊神经母细胞瘤 30例,原始神经外胚层肿瘤 5例,采用CDV化疗方案动员,观察采集干细胞效果。 结果与结论：所有病例化疗后第4~9天(平均6.5 d)白细胞< 2×10⁹ L^-1,给予粒细胞刺激因子5~10 mg/kg刺激造血,化疗后13~19 d(平均15.5 d)至白细胞> 5×10⁹L^-1后开始采集。所有病例均采集到足够的单个核细胞数和CD34⁺细胞,总采集次数1~4次,平均2.1次,单个核细胞：(6.1±1.2)×10⁸/kg,CD34⁺细胞为(5.3±0.8)×10⁶,锥虫蓝拒染率：99.5%(99%~100%),动员并发症少,患儿均能耐受。其中25例进行自体外周血干细胞移植后均获快速造血功能重建,白细胞开始回升(中性粒细胞绝对值>0.5×10⁹ L^-1)时间为移植后10~20 d(平均14d)血红蛋白恢复(> 80 g/L)的时间为移植后10~30 d(平均18 d),血小板恢复(> 20×10⁹ L^-1)时间为移植后12~35 d(平均20 d)。结果提示CDV 方案可以安全有效地完成神经母细胞瘤及原始神经外胚层肿瘤患儿自体外周血干细胞动员和采集。     

Cytoreduction of lymphoid malignancies and mobilization of blood hematopoietic progenitor cells with high doses of cyclophosphamide and etoposide plus filgrastim.

We evaluated the efficiency of high doses of cyclophosphamide (6 g/m²) and etoposide (2 g/m²) plus filgrastim (granulocyte colony-stimulating factor; G-CSF) to mobilize autologous hematopoietic progenitor cells in patients with non-Hodgkin lymphoma, multiple myeloma, and Waldenström macroglobulinemia. We also evaluated the safety of this regimen and the engraftment kinetics after myeloablative chemotherapy. Seventy-nine patients with high-risk or relapsed/primary refractory non-Hodgkin lymphoma, multiple myeloma, or Waldenström macroglobulinemia were treated. The mobilizing regimen was as follows: cyclophosphamide 600 mg/m² twice daily for 10 doses, etoposide 200 mg/m² twice daily for 10 doses (continuous; n = 57) or 2 g/m² over 10 hours on day 5 of etoposide (bolus; n = 22), and G-CSF 5 μg/kg/d beginning day 14. Fifty-nine percent of patients achieved the primary end point (a CD34 cell dose of 5 million per kilogram with a single leukapheresis). More bolus etoposide patients achieved the primary end point (86%) compared with continuous etoposide patients (47%; P < .0001). The CD34 cell dose collected was greater in bolus etoposide patients (44 million per kilogram) than in continuous etoposide patients (10.9 million per kilogram; P < .0001). Patients took 3 weeks to recover >500/μL neutrophils and >20000/μL platelets after cyclophosphamide and etoposide. The overall response rate was 69% for non-Hodgkin lymphoma patients and 71% for multiple myeloma/Waldenström macroglobulinemia patients. The treatment-related mortality was 2.5%. Sixteen percent of surviving patients experienced grade ≥3 nonhematologic toxicity. Patients receiving bolus etoposide had significantly less grade ≥2 oral mucositis, less use of total parenteral nutrition, and less need for red blood cell and platelet transfusions. Sixty-four patients (81%) underwent autologous hematopoietic progenitor cell transplantation, with prompt engraftment. Four patients (5%) did not undergo autologous hematopoietic progenitor cell transplantation because of toxicity from high-dose cyclophosphamide and etoposide. We conclude that high doses of cyclophosphamide and etoposide combined with G-CSF are an efficient and safe mobilizing regimen for the collection of hematopoietic progenitor cells during aggressive cytoreduction of tumor burden in patients with lymphoid malignancies.     

Improved mobilization of peripheral blood CD34+ cells and dendritic cells by AMD3100 plus granulocyte-colony-stimulating factor in non-Hodgkin's lymphoma patients

AMD3100 is a drug capable of mobilizing peripheral blood stem cells (PBSCs) in donors and in cancer patients as a single agent or in combination with granulocyte-colony-stimulating factor (G-CSF). We initiated a phase II study of 11 refractory or relapsed non-Hodgkin's lymphoma (NHL) patients, receiving 16 microg/kg daily of G-CSF for 4 days followed by 240 microg/kg of AMD3100 given subcutaneously on a new schedule of 9-10 h before apheresis collection on day 5. Our aims were to assess the effect of AMD3100 on the mobilization of CD34+ cells, dendritic cells (DCs) and lymphoma cells. Administration of G-CSF and AMD3100 were continued daily until >or=2 x 10(6) CD34+ cells/kg were collected. Adequate collection of the target of CD34+ cells was achieved in all but 1 patient within 2 days, and 10/11 patients were transplanted within 2 months. All transplanted patients engrafted with a mean of 10 and 12 days for neutrophils and platelets, respectively. Addition of AMD3100 to G-CSF resulted with >2.5-fold increase in CD34+ cells/microl (p = 0.0001) and in a >2-fold increase in pDC1 and pDC2 cells/microl (p = 0.003). Adverse events related to AMD3100 were minimal. AMD3100 was generally safe and improved PBSC and DC cell mobilization with no apparent contamination of lymphoma cells.