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Bone marrow transplantation from partially HLA-mismatched family donors for acute leukemia: single-center experience of 201 patients.

Summary:Between February 1993 and December 1999, 201 patients (1–59 years old, median 23) with acute leukemia (67% not in remission) underwent ex vivo T-cell-depleted (TCD) bone marrow transplants (BMT) from partially mismatched related donors (PMRD; 92% mismatched for 2–3 HLA A, B, DR antigens). Conditioning comprised total body irradiation, cyclophosphamide, cytarabine, etoposide, anti-thymocyte globulin (ATG), and methylprednisolone. Graft-versus-host disease (GVHD) prophylaxis comprised partial TCD with OKT3 (n=143) or T10B9 (n=58), steroids, ATG, and cyclosporine. The engraftment rate was 98%. The cumulative incidences of grades II–IV acute GVHD and chronic GVHD were 13 and 15%, respectively. The 5-year cumulative incidences of relapse and transplant-related mortality (TRM) were 31 and 51%, respectively. The actuarial 5-year overall survival (OS) and disease-free survival (DFS) probabilities were 19 and 18%, respectively. Patient age >15 years, active disease at transplant, donor age >25 years, and 3-antigen donor mismatch (host-versus-graft) affected the outcome adversely. The actuarial 5-year OS of four groups of patients identified based upon these risk factors was 39, 20, 13, and 0%, respectively (P<0.0001). We conclude that PMRD BMT is a potential treatment option for patients with high-risk acute leukemia who require an alternative donor transplant and fall into a group with a reasonable expected outcome.

De novo chronic graft-versus-host disease presenting as hemolytic anemia following partially mismatched related donor bone marrow transplant

Chronic graft-versus-host disease (cGVHD) is a disease of immune dysregulation that resembles an autoimmune disease. It usually involves the skin, mucosal and serosal surfaces and, less commonly, the hematopoietic system. We report hemolytic anemia (HA) as the primary manifestation of de novo cGVHD in recipients of partially mismatched related donor transplants. Five of 40 eligible patients developed HA at a median of 168 days post-transplant. Recipients were mismatched for one to three major HLA antigens. Conditioning therapy consisted of total body irradiation, etoposide, Ara-C, cyclophosphamide and steroids. GVHD prophylaxis included partial T cell depletion, using anti α/β CD3 antibody (T10B9) and complement, in addition to post-transplant immunosuppression. At presentation, all patients were receiving cyclosporine with or without low-dose steroids. Along with a mean Hb of 7.1g%, patients had an increased reticulocyte count, a mild raised lactic dehydrogenase and a positive Coombs’ test (in 2/5 patients). Four patients had also demonstrated a decrease in platelet count. Treatment was initiated with high-dose steroids and intravenous gamma globulin and response was observed within 1 week. Awareness of this presentation of cGVHD and early therapeutic intervention can result in successful reversal of presumed immune-mediated red cell and platelet destruction.

Influence of T cell depletion method on circulating γδ T cell reconstitution and potential role in the graft-versus-leukemia effect

Background Our laboratory previously reported that leukemia patients who developed ≥ 10% γδ + T cells during the first six months after receiving an anti-TCRαβ T-cell-depleted (TCD) graft from a partially mismatched related donor (PMRD) had a disease-free survival (DFS) advantage. These γδ + T cells were Vδ1 + CD3 + CD4 − CD8 − CD69 + HLADR + and are cytotoxic to K562 cells. Methods In order to determine whether the anti-αβ TCD regimen was associated with these findings, we compared the reconstitution of γδ + T cells from patients who received TCD PMRD grafts using the anti-TCRαβ MAb T10B9-1A31 (previously reported) with similar patients who received grafts using the anti-CD3 MAb OKT3. Results Increased cytotoxic Vδ1 + T cells were seen in 10 of 43 T10B9 TCD patients compared to 7 of 100 in the OKT3 TCD group (23% versus 7%, p=0.010). T10B9 patients with increased γδ + T cells also exhibited a higher range of increased γδ + T cells and the length of time the γδ + T cells remained high was longer when compared to OKT3 patients. Patients with increased γδ + T cells whose grafts were T-cell depleted with T10B9 showed a significant decrease in relapse (p = 0.038). Similar rates and reduction in relapse were seen in OKT3 TCD patients, although significance was not reached due to the small number of patients with increased γδ + T cells. Estimated 3 year disease-free survival was significantly improved in T10B9 patients with increased γδ + T cells (0.79 versus 0.31, p=0.009), a trend also seen in OKT3 patients (p = 0.091). Discussion These observations indicate that Vδ1 + CD4 − CD8 − cytotoxic T cells are associated with lower relapse rates and improved survival, and thus may have a role in a graft-versus-leukemia effect.

Expression of CD134 (0X-40) on T cells during the first 100 days following allogeneic bone marrow transplantation as a marker for lymphocyte activation and therapy-resistant graft-versus-host disease.

CD134 (OX-40) is an activation-associated antigen which functions as a costimulatory receptor for CD4+ T cells. In order to determine the expression of CD134 during immune recovery following allogeneic bone marrow transplantation (BMT), we measured its expression on T cells and T cell subsets during the first 100 days following BMT in 26 patients. CD4+CD134+ T could be seen approximately 14 days following BMT cells in patients who did not develop GvHD which required therapy (n = 20). The percentage of CD4+CD134+ cells continued to increase up to the fourth week following BMT to a maximum of 40-50% of CD4+ T cells (normal = 1-8%). Two patients who developed Grade I-II GvHD and who responded to treatment with pulsed high-dose methylprednisolone (MPD) showed a decline of approximately 40% in CD4+CD134+ T cells was seen within 48 hours of treatment. Four patients who developed GvHD that was not responsive to MPD and who later developed high IV GvHD showed increasing CD4+CD134+ T cells up to 85% of the CD4+ T cells. Additionally, rapid increases in CD134+ T cells following antibody-based T cell therapy were associated with GvHD recurrence. In no cases was the percentage of CD134+ CD4+ T cells predictive of clinical GvHD. In this exploratory study, we have shown that CD134, although not predictive of the initial onset of GvHD, may be a useful tool for monitoring the response to early GvHD therapy and identification of patients at risk for reemergence of GvHD who may benefit from anti-T cell therapy. Cytometry (Comm. Clin. Cytometry) 38: 238-243, 1999.

Assessment of G-CSF stimulated BM hematopoietic stem cells in normal donors

BACKGROUNDnThe clinical use of G-CSF has recently been expanded to include mobilization of stem cells for both autologous and allogeneic transplantation. Most of the published studies have focused on stem cells released into the peripheral blood (PB) after G-CSF treatment. However, little is known about the effects of G-CSF on BM. This study evaluated the concurrent effects of short-term G-CSF on both BM and PB stem and progenitor cells in normal individuals.nnnMETHODSnVolunteers received 5 or 10 microg/kg of G-CSF for 5 consecutive days (Days 1-5). On Days 0, 3, 6, 9 and 15, BM and PB samples were obtained. Flow cytometry and functional assay were performed to analyze stem cells, subpopulations, adhesion molecules, colony-forming units and LTCIC.nnnRESULTSnThe total nucleated cells and absolute numbers of CD34(+)/mL showed a similar response pattern in both BM and PB, with a peak around Day 6 that returned to baseline levels by Day 15. However, there was a reciprocal change in the percentage of CD34(+) cells between BM and PB compartments. The expressions of adhesion molecule showed an up- and down-regulation of alpha4 and alpha5 integrin subunits, respectively, also correlated with the CD34(+) mobilization patterns.nnnDISCUSSIONSnThe functional characterization of integrins, and further clinical examination of G-CSF-stimulated BM is warranted. G-CSF-stimulated BM maybe considered as an alternative source of stem cells in transplantation.

Comparison of immune recovery in recipients of unmanipulated vs T-cell-depleted grafts from unrelated donors in a multicenter randomized phase II-III trial (T-cell depletion trial)

Comparison of immune recovery in recipients of unmanipulated vs T-cell-depleted grafts from unrelated donors in a multicenter randomized phase II–III trial (T-cell depletion trial)

In vitro interactions between γδT cells, DC, and CD4 + T cells; implications for the immunotherapy of leukemia

Background : n i T cells contribute to immune defense against infectious organisms and some malignancies, but the process of activation and proliferation of these cells is not well understood. It is known that the immune response of n i T cells is not MHC-dependent, but is likely based on direct recognition of surface peptides and non-peptide ligands. This study examined whether DCs and CD4 + T cells can participate in the activation of n i T cells. Method : Peripheral blood n i T cells were co-cultured with CD34-derived autologous DCs and CD4 + T cells using contact-dependent cultures and transwell systems. Proliferation, immunophenotyping, and cytotoxicity assays determined the extent of n i T cell proliferation and cytotoxicity. Results : Human n i T cells expanded 221.3 - 76-fold in cultures with DCs, and 165.7 - 76.6-fold with CD4 + T-cells alone. Proliferation was enhanced (1949.8 - 261.3-fold) when n i T cells were cultured with both ...