Search PubMed⌕ Search

Biomedical subjects

R Storb

Publications and source records attributed to R Storb.

At least 199 records · Page 11Linked to original sources

Factors influencing collection of peripheral blood stem cells in patients with multiple myeloma.

This study was performed to determine the factors influencing the collection of autologous peripheral blood stem cells (PBSC) in patients with multiple myeloma (MM) who had disease which had progressed after an initial response or who had refractory disease. Fifty-seven patients with MM underwent PBSC collections following recombinant human granulocyte colony stimulating factor (G-CSF) alone (n = 19) (16 micrograms/kg/day), cyclophosphamide (CY) (4 gm/m2 x 1) with either G-CSF (10 micrograms/kg/day) (n = 7) or granulocyte-macrophage colony-stimulating factor (GM-CSF) (500 micrograms/m2/day) (n = 7) or cyclophosphamide (4 gm/m2 x 1) and etoposide (200 mg/m2/day x 3) (CE) with G-CSF (10 micrograms/kg/day) (n = 24). The goal was to collect 5 x 10(6) CD34+ cells/kg. Fifty of 57 patients underwent autologous transplantation with PBSC alone (n = 39) or PBSC + marrow (n = 11). The median yield of CD34+ cells was 7 x 10(6)/kg (range 0-178.3). Thirty-nine of 57 patients (68%) achieved the target level of 5 x 10(6) CD34+ cells/kg in a median of three (range 1-8) collections. Eighteen (32%) patients yielded < 5 x 10(6) CD34+ cells/kg with the first collections. Thirteen of these 18 patients yielded < 2.5 x 10(6) and five yielded 2.5-4.95 x 10(6) CD34+ cells/kg. Of the 18 patients with less than optimal CD34+ cell yields, five with CD34+ yields of 2.5-4.95 x 10(6)/kg received PBSC alone at transplant, six underwent marrow storage to augment the PBSC dose and received PBSC plus marrow and seven patients underwent secondary collections. Of seven patients who underwent second (n = 5) or third (n = 2) cycles of PBSC collections using G-CSF 16 (n = 4) or 32 (n = 3) micrograms/kg/day, > 2.5 x 10(6) CD34+ cells/kg were collected in four patients. Two patients achieved < 0.18 CD34+ cells following three cycles of mobilization. In a linear regression model, an increased percentage of marrow involvement and prior radiotherapy (RT) were statistically significantly associated with a low CD34+ cell collection yield (P = 0.003, and 0.01, respectively). A mobilization regimen of CE plus G-CSF was associated with a significantly higher yield of CD34+ cells as compared to patients receiving G-CSF alone (P = 0.02). CY with G or GM-CSF was not significantly different than G-CSF alone (P = 0.49). Twenty-two of 24 (92%) patients receiving CE with G-CSF achieved a target level of 5 x 10(6) CD34+ cells/kg or more as compared to 11 of 19 (58%) patients receiving G-CSF alone (P = 0.01) and six of 14 (43%) patients receiving CY with G or GM-CSF (P = 0.001). These data suggest that percentage of marrow involvement, prior radiotherapy, and number of prior chemotherapy regimens are important predictors of PBSC yield in patients with MM. These data also suggest that CE plus G-CSF is superior to G-CSF alone or CY plus G/GM-CSF based on mean daily CD34+ cell collection yield. Higher doses of G-CSF (16-32 micrograms/kg/day) can result in adequate CD34+ cell collections in some secondary attempts in patients with MM failing an initial mobilization regimen.

Adult↗

Phase II study of high-dose busulfan, melphalan and thiotepa with autologous peripheral blood stem cell support in patients with malignant disease.

The purpose of this study was to determine the toxicities and potential effectiveness of high-dose busulfan, melphalan and thiotepa (Bu/Mel/TT) followed by autologous peripheral blood stem cell (PBSC) infusion in patients with a variety of diseases. A phase II clinical trial of Bu (12 mg/kg), Mel (100 mg/m2) and TT (500 mg/m2) followed by PBSC infusion in 104 patients with breast cancer (n = 48), malignant lymphoma (n = 25), ovarian cancer (n = 13), multiple myeloma (n = 7) and other malignancies (n = 11) was performed. Sixty-two patients were treated in an academic medical center and 42 in a community cancer center. Grade 3-4 regimen-related toxicities occurred in 14% of patients, causing regimen-related mortality in six (6%) patients with an overall transplant-related mortality of 9%. Transplant-related deaths occurred in 6/62 patients (10%) treated in an academic medical center and in 3/42 (7%) treated in a community cancer center. Complete remissions (CR) were achieved in 1/17 (6%) patients with refractory stage IV breast cancer, 4/4 patients with responsive stage IV breast cancer, 6/13 (46%) with more-advanced lymphoma and 4/4 with less-advanced lymphoma. These patients are alive and disease-free a median of 712, 279, 461 and 404 days after transplant, respectively. Nineteen of 22 patients with stage II-III breast cancer remain alive and disease-free a median of 365 days after transplant. Complete remissions were also seen in 4/9 patients with ovarian cancer and 3/7 with multiple myeloma. The Bu/Mel/TT regimen followed by autologous PBSC infusion is associated with acceptable morbidity and mortality, appears to have significant activity in patients with breast cancer and is well tolerated in the adjuvant setting of stage II-III breast cancer. Bu/Mel/TT also appears to have significant activity in patients with lymphoma, multiple myeloma and possibly ovarian cancer. Further phase II-III studies are warranted in patients with these and other malignancies.

Adolescent↗

Autologous transplantation with peripheral blood stem cells collected after granulocyte colony-stimulating factor in patients with acute myelogenous leukemia.

The use of peripheral blood stem cells (PBSC) with or without bone marrow (BM) in patients with acute myelogenous leukemia (AML) undergoing autologous transplantation in untreated first relapse (Rel1) or in second remission (CR2) was evaluated in a phase II study. Twenty-three patients with AML in untreated Rel1 (n = 8) and CR2 (n = 15) underwent autologous transplant using PBSC with (n = 19) or without (n = 4) BM. Six patients received busulfan (BU) and cyclophosphamide (CY) and 17 received BU, CY and total body irradiation prior to transplant. The median number of CD34+ cells infused was 4.81 x 10(6)/kg (range 0.04-15). Fifteen of 23 patients received post-transplant interleukin-2 (IL-2) at a median of 43 days (range 11-93) in an attempt to decrease relapses. The median day of recovery of granulocytes to 0.5 x 10(9)/I was 12 (range 8-27) and platelets to 20 x 10(9)/I was 15 (range 8-103). Patients received a median of 4 units (range 0-20) of red blood cells and 29 units (range 4-252) of platelets. The probability of 100 day non-relapse mortality was 0.14. The probabilities of survival and relapse at 2 years were 0.24 and 0.65, respectively. The probabilities of relapse in patients receiving (n = 15) and not receiving (n = 8) interleukin-2 (IL-2) were 0.59 and 0.74, respectively (P = 0.1). Overall, seven of 23 (30%) patients are alive and continuously disease-free at a median of 483 days (range 113-835) post-transplant. These data demonstrate that the infusion of PBSC collected after rhG-CSF corrected engraftment problems previously observed with autologous BM transplants in patients with AML but was associated with a high relapse rate.

Acute Disease↗

High-dose fractionated total-body irradiation, etoposide and cyclophosphamide for treatment of malignant lymphoma: comparison of autologous bone marrow and peripheral blood stem cells.

Consecutive patients with non-Hodgkin's lymphoma (NHL, n = 133) or Hodgkin's disease (HD, n = 20) were treated with 12.0 Gy of fractionated total body irradiation, etoposide 60 mg/kg, and CY 100 mg/kg followed by infusion of autologous hematopoietic stem cells. Seventy-nine patients received purged (n = 62) or unpurged BM (n = 17), and 74 received unpurged PBSCs alone (n = 56) or with BM (n = 18). The median day for achieving a sustained granulocyte count of 0.5 x 10(9)/I was 14 range (7-66) for BM recipients and 10 (7-30) for PBSC +/- BM recipients (P = 0.03). A platelet count of 20 x 10(9)/I was achieved at a median of day 24 (6-145) in BM recipients and day 11 (range, 7-56) in PBSC +/- BM recipients (P = 0.007). The median number of platelet units transfused was 86 (0-1432) for BM recipients and 30 (6-786) for PBSC +/- BM recipients (P = 0.001). The median number of hospital days was 36 (10-88) for BM recipients and 27 (14-76) for PBSC +/- BM recipients (P = 0.0001). The unadjusted Kaplan-Meier (KM) estimates of survival, event-free survival (EFS) and relapse at 2 years were 0.57, 0.45 and 0.43 for patients receiving BM and 0.55, 0.36 and 0.59 for patients receiving PBSC +/- BM. After adjusting for confounding variables, the estimated relative risk (RR) of death from any cause was 0.92 (P = 0.75), of relapse was 1.25 (P = 0.39), of non-relapse mortality was 0.71 (P = 0.42) and of mortality and/or relapse was 1.17 (P = 0.48) for patients receiving PBSC +/- BM as compared to BM. For 46 patients with NHL receiving unpurged PBSC alone, the unadjusted KM estimate of relapse was 0.61 compared with 0.48 for 52 comparable patients receiving purged BM, while the RR for relapse for patients receiving unpurged PBSCs was 1.37 (P = 0.33) after adjusting for other significant covariates. These data confirm previous observations that patients who receive PBSC +/- BM have faster engraftment, fewer transfusions and shorter hospital stays than patients who receive only BM. There were no statistically significant differences between the two groups in survival, relapse, death from causes other than relapse and event-free survival.

Adolescent↗

Syngeneic marrow transplantation in patients with multiple myeloma.

Eleven patients with advanced multiple myeloma (MM) received syngeneic marrow (n = 10) or peripheral blood stem cell (n = 1) transplants following cyclophosphamide (CY) and total body irradiation (TBI) (n = 8), busulfan (Bu) and CY (n = 1), Bu, CY and TBI (n = 1) or Bu, melphalan and thiotepa (n = 1). At the time of transplant one patient had stage II and 10 patients had stage III disease. Four patients had refractory disease, two had chemotherapy sensitive disease and five had progressed after an initial response to chemotherapy. The median time from diagnosis to transplant was 353 days (range 176-6118). After transplant, the median time to achieve granulocytes of 0.5 x 10(9)/l and platelets of 20 x 10(9)/l was 12 days (range 9-20) and 12 days (9-27), respectively. One patient died of interstitial pneumonia syndrome on day 32 and one died of veno-occlusive disease of the liver on day 44 post-transplant, and these were unevaluable for response. Five of nine evaluable patients achieved a complete response (CR), three a partial response, and one patient had no response. Three patients who did not achieve CR died of progressive disease 106, 142 and 321 days post-transplant. Of five patients who achieved a CR, three relapsed on days 539, 737 and 1706 and died on days 1759, 1596 and 1736, respectively; one patient died of myelodysplastic syndrome on day 1407 without evidence of MM and one patient is alive and disease-free 3297 days after transplant. One of the two long-term survivors has a persistent monoclonal protein in the blood 15 years post-transplant. These data show that high-dose therapy and infusion of normal syngeneic marrow cells can cure a small fraction of patients with MM. However, the majority of patients did not achieve durable CR, demonstrating the need for improved transplant conditioning regimens, earlier transplant or additional post-transplant treatment strategies when syngeneic transplants are performed.

Adult↗

Effect of mixed chimerism on graft-versus-host disease, disease recurrence and survival after HLA-identical marrow transplantation for aplastic anemia or chronic myelogenous leukemia.

The association of mixed (donor/host) chimerism with graft-versus-host disease (GVHD), graft rejection, disease recurrence and survival was investigated in 116 patients with aplastic anemia and 197 patients with chronic myelogenous leukemia (CML) transplanted with unmodified marrow from an HLA-identical sibling donor of opposite sex. Patients with aplastic anemia were conditioned with cyclophosphamide (CY), patients with CML were conditioned with a combination of CY and total body irradiation (TBI) or busulfan. Sixty-three of the patients with aplastic anemia (54%) and 100 patients with CML (51%) were categorized as mixed chimeras based on the concurrent presence of donor and host lymphohematopoietic cells 14 days or later after transplantation. The TBI dose used for conditioning was inversely correlated with the development of mixed chimerism (P < 0.0001) among CML patients. No other patient- or transplant-related parameter was identified which contributed significantly to the development of mixed chimerism. The incidence of rejection was higher but not significantly so in patients with aplastic anemia who were mixed chimeras. The incidence of leukemic relapse in patients with CML who were mixed chimeras was increased only if mixed chimerism occurred after day 100 (P = 0.015). The incidence of acute GVHD (grades II-IV) was lower in mixed chimeras than in complete chimeras, but this difference was statistically significant only for patients with aplastic anemia given single-agent GVHD prophylaxis (P = 0.0008). Mixed chimeras in that group also had a better survival than complete chimeras, while no significant difference was observed in patients with aplastic anemia given drug combinations for GVHD prophylaxis. Among patients with CML, both overall survival (P = 0.03) and relapse-free survival (P = 0.04) were significantly superior in mixed than in complete chimeras. Thus, mixed chimerism was frequent among patients with aplastic anemia and with CML and was not uniformly associated with graft failure or leukemic relapse. The interaction between conditioning regimen, GVHD prophylaxis and chimerism are complex. The survival advantage of mixed chimeras is only in part related to a lower incidence of GVHD and other factors are likely to contribute.

Adolescent↗

A controlled trial of long-term administration of intravenous immunoglobulin to prevent late infection and chronic graft-vs.-host disease after marrow transplantation: clinical outcome and effect on subsequent immune recovery.

To determine whether intravenous immunoglobulin (IVIg) given monthly from day 90 to day 360 posttransplantation decreased the incidence of late infection, chronic graft-vs.-host disease (GVHD), and obliterative bronchiolitis after marrow transplantation, patients were assigned randomly to receive either IVIg (500 mg/kg/month) or no IVIg prophylaxis. Participants were registered before transplantation, and 250 patients (123 IVIg and 127 control) were evaluable for events after day 100. The two groups were balanced for age, marrow source, cytomegalovirus (CMV) seropositivity, pretransplantation conditioning, and prophylaxis for infection and GVHD. Between days 100 and 365 posttransplantation, the incidence of bacteremia or septicemia per 100 patient-days of risk was 0.10 in the IVIg group and 0.12 in the controls (p = not significant). During the same period, the incidence of localized infection was marginally higher in control patients than in IVIg recipients (0.44 vs. 0.24, respectively; relative risk [RR] 1.46, p < 0.07). Administration of IVIg prophylaxis had no effect on survival, the incidence of obliterative bronchiolitis, severity of airflow obstruction, or the incidence or mortality of chronic GVHD. After discontinuing IVIg prophylaxis at day 360, subsequent recovery of endogeneous humoral immunity was impaired (serum IgG1 and IgA levels were significantly lower than controls at day 730), and total infections were less common in the second year in control patients than in former IVIg recipients (0.12 vs 0.19, respectively; RR 0.61, p = 0.03). We conclude that in the absence of hypogammaglobulinemia, monthly administration of IVIg given from day 90 to 360 does not reduce late complications and may impair long-term humoral immune recovery after marrow transplantation.

Adolescent↗

Barriers to bone marrow transplantation for sickle cell anemia.

While allogeneic marrow transplantation is curative therapy for patients with sickle cell anemia, only a small fraction of patients in the United States receive this treatment. We surveyed participants in our multicenter study of marrow transplantation for sickle cell anemia to determine reasons for not proceeding to transplantation. Among the 4848 patients less than 16 years of age with sickle cell anemia that were followed in 22 collaborating centers, 315 (6.5%) patients were reported to meet protocol entry criteria for transplantation, although there was wide variation among the institutions (0.9-36%). Among the 315 patients eligible for transplantation, 128 (41%) had human leukocyte antigen (HLA) typing performed, and of these 44 (14% of those meeting entry criteria) had an HLA-identical sibling. Common reasons for not proceeding with HLA typing in the remaining 187 patients included lack of a candidate sibling donor (76 patients, 24% of those meeting criteria) and lack of financial or psychosocial support (33, 10.5%). Parental refusal (30, 9.5%), physician refusal (13, 4%), history of medical noncompliance (2, < 1%), and other reasons (33, 10.5%) were less frequently cited. To date, 25 patients have been transplanted. Of the remaining 19 patients with HLA-matched donors, seven did not proceed to transplantation because of parental refusal, while the others anticipate a future transplantation (6), have experienced symptomatic improvement (4), or have relocated abroad (2). We conclude that the major barrier to marrow transplantation for sickle cell anemia is lack of an HLA-identical donor. But since only 6.5% of all children with sickle cell disease were considered eligible for transplantation, it is possible that other significant obstacles remain to be identified. For patients reported to meet eligibility criteria, parental refusal and limited financial or psychosocial support were infrequent barriers to transplantation.

Anemia, Sickle Cell↗

Delay of radiation-induced decline and recovery of hematopoiesis following treatment with anti-HLA-DR antibody.

A dose of 200 cGy of total-body irradiation (TBI) is nonlethal in dogs: Following a granulocyte nadir in the third week post-TBI, peripheral blood cell counts recover to normal values by about 5 weeks. In the context of studies on a potential role of major histocompatibility (MHC) class II antigens in the regulation of stress hematopoiesis, we tested the effect of anti-MHC class II monoclonal antibodies (mAbs) on hematologic recovery after TBI. Thirteen dogs were given 200 cGy of TBI not followed by marrow infusion. Five received no additional treatment (concurrent controls) and eight were given daily intravenous (IV) injections of anti-class II mAbs H81.9 (anti-HLA-DR; n = 6) or B1F6 (anti-HLA-DR and -DP; n = 2) at 0.6 (n = 4) or 1.2 mg/kg/d (n = 4) on days 0-4 (n = 7) or days 0-9 (n = 1). One control dog died early from an intercurrent infection and four recovered uneventfully. Dogs given mAbs after TBI showed significantly different granulocyte and platelet kinetics. The granulocyte nadir was lower (p = 0.09) and was reached later (p = 0.005), the duration of neutropenia was longer (p = 0.08), and recovery occurred later (p = 0.02) than among controls. Similarly the platelet nadir was lower (p = 0.05), thrombocytopenia lasted longer (p = 0.02), and recovery occurred later (p = 0.02) than among controls. Four of eight mAb-treated dogs died with marrow aplasia. We propose that following irradiation, HLA-DR mediated signals result in terminal differentiation in more mature hematopoietic precursors but interfere with replication or differentiation in early hematopoietic precursors. These observations suggest a role for MHC class II molecules in the regulation of stress hematopoiesis.

Animals↗

Marrow transplantation for hepatitis-associated aplastic anemia: a follow-up of long-term survivors.

Between 1971 and 1989 we have treated 19 patients with hepatitis-associated aplastic anemia by marrow transplantation from their HLA-identical siblings following conditioning with 200 mg/kg cyclophosphamide (Cy) administered over a period of 4 days. One patient failed to engraft by day 34 and was given a second transplantation. He died from infection 15 days after the second transplantation. Eighteen patients had sustained engraftment. Six patients developed acute graft-vs.-host disease (GVHD) and two of these patients died 2.8 and 3.3 months after transplantation. Fifteen patients are surviving 4 to 24 (median 13) years after transplantation, while one patient died in a car accident 17 years after successful transplantation. Six of the surviving patients developed chronic GVHD. Two of the patients with chronic GVHD had preceding acute GVHD and four did not. Five of the six patients with chronic GVHD received donor buffy coat cells in addition to the marrow inoculum to prevent graft rejection. Twelve of the 15 surviving patients have Karnofsky performance scores of 100%. One patient, living more than 4 years after transplantation, has a Karnofsky score of 40% because of persistent cognitive deficits following non-A, non-B hepatitis with hepatic coma. Two patients developed hepatitis C infection 12 and 18 years after transplantation, respectively. Except for mild fatigue and mildly elevated liver function tests, these patients are doing well with Karnofsky performance scores between 95 and 100%. One patient developed severe coronary artery disease 10 years after transplantation, decreasing his Karnofsky performance score to 80%. Serum samples before and after transplantation from 13 patients were tested for hepatitis B virus (HBV) DNA and hepatitis C virus (HCV) RNA by polymerase chain reaction (PCR). Only one patient tested positive for HCV RNA before transplantation. Seven of 15 sera were hepatitis C RNA-positive posttransplantation, but only one of these patients has developed active hepatitis C. All 13 patients were were negative for hepatitis B surface antigen and HBV DNA. Only one patient had IgM antibodies against hepatitis A virus (HAV) before transplantation, which suggested HAV infection. Hepatitis-associated aplastic anemia apparently was caused in most patients by a non-A, non-B, non-C agent. HLA-identical marrow transplantation for hepatitis-associated aplastic anemia with Cy as conditioning regimen is well-tolerated and has a long-term event-free survival in excess of 80%, not different from results of marrow transplantations for aplastic anemia of other etiologies.

Adolescent↗

Relevance of marrow fibrosis in bone marrow transplantation: a retrospective analysis of engraftment.

A retrospective study compared posttransplant engraftment parameters in 203 patients with myelofibrosis (MF) with those in a population of 203 matched controls without MF. There were no significant differences between these groups in the proportions of patients who died without achieving engraftment and in the disease-free survival distributions. Furthermore, comparisons between the two groups of patients reaching the respective endpoints showed no differences in the time distributions for reaching 0.5 or 1.0 x 10(9)/L granulocytes, but the time to platelet transfusion independence was 3 days longer in patients with MF. In further analysis, results for 33 patients with severe MF were compared with those of their respective controls. The proportions of patients with severe MF who died without reaching these engraftment endpoints and the disease-free survival distributions in the two groups were similar. Among patients who reached the respective engraftment endpoints, there was no statistically significant difference in the pace of granulocyte recovery. In patients with severe MF, there was a 7-day delay in the time to reach platelet transfusion independence and a 2-day delay in the time to reach red blood cell independence, but the differences were not statistically significant. The present results do not substantiate concerns raised by earlier studies. MF may delay the time to reach platelet independence by approximately 3 days and may increase platelet transfusion requirements, but no other perturbation of hematopoietic reconstitution was apparent.

Adolescent↗

DLA-identical bone marrow grafts after low-dose total body irradiation: effects of high-dose corticosteroids and cyclosporine on engraftment.

Previous studies found that marrow allografts from DLA-identical littermates resulted in survival of 60% of recipient dogs after an otherwise lethal dose of 450 cGy of total body irradiation (TBI), either because of successful allografts or autologous recovery after rejection of the allografts. Forty percent of dogs died with marrow aplasia after allograft rejection. The current study asked whether allogeneic engraftment could be enhanced and survival improved by treating allograft recipients with high doses of corticosteroids or with cyclosporine (CSP), administered either before or after transplantation. Five dogs in group 1 received corticosteroids beginning on day -5 and ending on day 32 after transplant. The starting dose was 12.5 mg of prednisone per kilogram orally twice daily. All five dogs rejected their allografts; three died early with marrow aplasia and two showed endogenous marrow recovery. Nine dogs received CSP from day -6 to day -1 before transplantation at a dose of 20 mg/kg/d intravenously administered in divided doses. All nine dogs rejected the marrow allograft; six died with marrow aplasia and three survived with endogenous marrow recovery. Seven dogs received CSP after transplantation at a dose of 30 mg/kg/d orally from day -1 to day 35. All seven had sustained allografts (two mixed chimeras and five complete donor-type chimeras) and became healthy long-term survivors without graft-versus-host disease. These results extend previous observations and confirm that grafts of marrow from DLA-identical littermates improved survival of dogs exposed to low but otherwise lethal doses of TBI. Additional therapy with high-dose corticosteroids administered peritransplantation and posttransplantation or CSP administered before transplantation neither enhanced the rate of allogeneic engraftment nor improved survival; however, CSP administered after transplantation resulted in successful allografts and event-free survival in all cases.

Adrenal Cortex Hormones↗

Unrelated donor marrow transplantation in children.

Eighty-eight children 0.5 to 17 years of age (median, 9 years of age) received an unrelated donor marrow transplant for treatment of chronic myeloid leukemia (CML; n = 16), acute lymphoblastic leukemia (ALL) in first or second remission (n = 15) or more advanced stage (n = 28), acute myeloid leukemia (AML; n = 13), or other hematologic diseases (n = 16) between June 1985 and April 1993. All patients were conditioned with cyclophosphamide and total body irradiation and received a combination of methotrexate and cyclosporine as graft-versus-host disease (GVHD) prophylaxis. Fourty-six patients received transplants from HLA-identical donors and 42 patients received transplants from donors who were minor-mismatched at one HLA-A or B or D/DRB1 locus. The Kaplan-Meier estimates of disease-free survival and relapse were 75% and 0% for patients with CML, 47% and 20% for ALL in first or second remission, 10% and 60% for ALL in relapse or third remission, 46% and 46% for AML in first remission (n = 1) or more advanced disease (n = 12), and 29% and 69% for other diseases. HLA disparity was not significantly associated with lower disease-free survival, but the results suggest more relapses in HLA-matched recipients and there was significantly more transplant-related mortality in mismatched recipients (51% v 24%, P = .04). Most deaths were due to infections associated with acute or chronic GVHD and occurred within the first 2 years after transplantation. Granulocyte engraftment occurred in all evaluable patients. Sixty-three percent of HLA-matched and 57% of HLA-mismatched recipients were discharged home disease-free at a median of 98 and 103 days, respectively, after transplantation (P = not significant [NS]). The incidence of grades II-IV acute GVHD was 83% in HLA-matched and 98% in HLA-mismatched recipients (P = .009). The incidence of chronic GVHD was 60% in HLA-matched and 69% in HLA-mismatched recipients (P = NS). One or multiple late adverse events such as cataracts, osteonecrosis of the hip or knee, restrictive or obstructive pulmonary disease, and hypothyroidism have occurred in 11 of 33 (33%) surviving patients. Immunosuppression was discontinued in 58% of surviving patients, including all 12 patients surviving more than 3.2 years, all of whom have a Lansky or Karnofsky score of 100%. These data show that marrow transplantation from fully or partially HLA-matched unrelated donors can be effective therapy for children with hematologic disorders and that pretransplantation disease status and posttransplantation GVHD remain important factors affecting patient outcome.

Adolescent↗

Thrombocytopenia in dogs induced by granulocyte-macrophage colony-stimulating factor: increased destruction of circulating platelets.

Administration of recombinant canine granulocyte-macrophage colony-stimulating factor (rcGM-CSF) to normal dogs in previous studies induced an increase in peripheral blood neutrophils and a dose-dependent decrease in platelet counts. In six dogs that received the highest tested dose of rcGM-CSF (50 micrograms/kg/d) for a minimum of 12 days, the mean nadir of the platelet count was 46,000/microL (range, 4,000 to 91,000/microL) on day 9 +/- 1.1 after starting therapy, compared with a mean baseline platelet count of 398,000/microL (range, 240,000 to 555,000/microL). In three dogs, survival of autologous 111In-labeled platelets was reduced from a mean of 4.9 days to 1.3 days during the administration of rcGM-CSF. Biodistribution studies with gamma camera imaging indicated that there was an increase in mean hepatic uptake during the administration of rcGM-CSF, from 15% to 44% of the total injected 111In-labeled platelets at 2 hours, whereas splenic uptake was not significantly changed. In contrast, in two evaluable dogs who were recipients of 111In-labeled platelets from matched allogeneic donors receiving rcGM-CSF, platelet survival was not reduced and no increased hepatic uptake was noted. A third dog became alloimmunized to the matched donor platelets and was not evaluable. Immunohistologic studies of liver and spleen were performed with monoclonal antibodies specific for canine gpIIb/IIIa and P-selectin in dogs treated with rcGM-CSF and compared with untreated controls. On treatment, a marked reduction of platelets in the red pulp of the spleen was evident, and in general, the presence of platelet antigen in the liver was unchanged. Therefore, platelets were not being sequestered, but destroyed in the liver and spleen. The platelet antigens, P-selectin and gpIIb/IIIa, were identified in association with Kupffer cells in the liver, but no difference in the number of distribution of these Kupffer cells was found between controls and rcGM-CSF-treated dogs. In the spleen during rcGM-CSF treatment, most platelet antigens were associated with large mononuclear cells in the marginal zone. During administration of rcGM-CSF, CD1c and CD11c expression was increased on Kupffer cells. Platelet P-selectin expression and binding of leukocytes to circulating platelets were unchanged from baseline studies with rcGM-CSF treatment. In conclusion, during the administration of rcGM-CSF to dogs, a local process in the liver and spleen is induced resulting in thrombocytopenia.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗