Graft-versus-host Disease In Recipients Research Articles

Donor CD8+ T cells facilitate induction of chimerism and tolerance without GVHD in autoimmune NOD mice conditioned with anti-CD3 mAb

AbstractPrevention of autoimmune diabetes and induction of islet transplantation tolerance in nonobese diabetic (NOD) mice can be reached by induction of mixed chimerism via bone marrow transplantation (BMT), but this procedure requires total body irradiation (TBI) conditioning of the recipients. The toxicity of radiation and potential for graft-versus-host disease (GVHD) prevents its clinical application. Donor CD8+ T cells play a critical role in facilitation of engraftment but also contribute to induction of GVHD in TBI-conditioned recipients. Here, we showed that high doses of donor CD8+ T cells in combination with bone marrow (BM) cells induced mixed chimerism without GVHD in NOD recipients conditioned with anti-CD3 monoclonal antibody (mAb). The prevention of GVHD in those recipients was associated with low-level production of inflammatory cytokines (ie, tumor necrosis factor α [TNF-α]), high-level production of anti-inflammatory cytokines (ie, interleukin 4 [IL-4] and IL-10), and confining of the donor CD8+ T-cell expansion to lymphohematopoietic tissues. The chimeric NOD recipients showed donor-specific tolerance and reversal of insulitis. These results demonstrate that donor CD8+ T-cell–mediated facilitation of engraftment can be separated from GVHD in nonirradiated recipients. This regimen may have potential application in the treatment of autoimmune disorders as well as induction of transplantation tolerance.

Donor CD8+ T Cells Facilitate Induction of Chimerism and Tolerance without GVHD in Autoimmune NOD Mice Conditioned with Anti-CD3 mAb.

Prevention of autoimmune diabetes and induction of islet transplantation tolerance in NOD mice can be reached by induction of mixed chimerism via bone marrow transplantation (BMT), but this procedure requires total body irradiation (TBI)-conditioning of the recipients. The toxicity of radiation and potential for graft versus host disease (GVHD) prevents its clinical application. Donor CD8+ T cells play a critical role in facilitation of engraftment, but also contribute to induction of GVHD in TBI-conditioned recipients. Here, we showed that high doses of donor CD8+ T cells in combination with bone marrow (BM) cells induced mixed chimerism without GVHD in NOD recipients conditioned with anti-CD3 mAb. The prevention of GVHD in those recipients was associated with low-level production of inflammatory cytokines (i.e. TNF-α), high-level production of anti-inflammatory cytokines (i.e. IL-4 and IL-10), and confining of the donor CD8+ T cell expansion to lymphohematopoietic tissues. The chimeric NOD recipients showed donor specific tolerance and reversal of insulitis. These results demonstrate that donor CD8+ T cell-mediated facilitation of engraftment can be separated from GVHD in non-irradiated recipients. This regimen may have potential application in the treatment of autoimmune disorders as well as induction of transplantation tolerance.

Hepatocyte Growth Factor Ameliorates Chronic Graft-Versus-Host Disease.

Since chronic graft-versus-host disease (GVHD) is a major cause of morbidity and mortality in allogeneic hematopoietic stem cell transplantation (HSCT), a new strategy to prevent chronic GVHD is necessary. We previously showed that hepatocyte growth factor (HGF) protected against lethal effects of acute GVHD and promoted T cell reconstitution in murine models (J Clin Invest 107;1365: 2001, Blood 2004 in press). We have now investigated whether HGF can protect against chronic GVHD. (C57BL/6 x DBA/2) F1 (BDF1) recipient mice were lethally irradiated (9 Gy) and co-transplanted with 5 x 106 bone marrow cells and 1.5 x 107 spleen cells from C57BL/6 donor mice. At the same time, mice were injected intramuscularly with 8 microgram of the human HGF gene, or with a control mock vector, every week using liposomes containing the hemagglutinating virus of Japan. Untreated GVHD recipients showed significant atrophy of the spleen and the thymus on day 56 after transplantation, while HGF treatment effectively prevented this atrophy. Splenic T cells from untreated GVHD recipients proliferated and produced significant amounts of IL-4 after being exposed to irradiated BDF1 spleen cells in vitro, while those from HGF-treated GVHD recipients did not. These results suggest that host-reactive type 2 T helper (Th2) cells were eliminated in the HGF-treated GVHD recipients by protection against thymic damage caused by acute GVHD, thereby preventing the progression to chronic GVHD. We next used DBA/2 into BDF1 models to determine the effect of HGF on another type of chronic GVHD. Chronic GVHD was induced by injection of DBA/2 spleen cells (9 x 107) into non-irradiated BDF1 mice. HGF treatment effectively prevented proteinuria and histological changes associated with glomerulonephritis. Liver sections of untreated GVHD recipients revealed prominent primary biliary cirrhosis (PBC)-like changes, as indicated by lymphocyte infiltration into the periportal area of the liver. HGF treatment effectively prevented these histological changes. HGF treatment greatly reduced the number of splenic B cells and the serum IgG and anti-DNA antibody levels. Furthermore, HGF treated GVHD recipients showed down-regulation of IL-4 mRNA expression in the spleen, liver and kidneys. IL-4 induction from DBA/2 CD4+ T cells stimulated by irradiated BDF1 CD11c+ dendritic cells (DCs) was significantly inhibited by addition of recombinant HGF (10 ng/ml) in vitro. Taken together, these results indicate that HGF can prevent chronic GVHD by eliminating host-reactive Th2 cells in the thymus, or by inhibition of Th2 cell induction by interaction with DCs.

Rat Bone Marrow Mesenchymal Stem Cells Cotransplanted with BM Improve Hematopietic Reconstitution and Immunoreconstitution with Alleviating Graft-versus-Host Disease.

Prolonged immunodeficiency after allogeneic bone marrow transplantation (BMT) causes significant morbidity and mortality from infection, while graft versus host disease (GVHD) after allogeneic BMT and immunosuppression therapies against GVHD further deteriorate this process. Adult bone marrow mesenchymal stem cells (MSC) have recently been shown to inhibit T-cell proliferation and reduce GVHD after allo-BMT. In this study, we characterized the effect of MSC on immunoreconstitution and hematopoietic-reconstitution after bone marrow transplantation. BMT model from Fischer344 rats (RT-1Al) to WF rats (RT-1Au) was established for this experiment. Effects of MSCs on hematopoietic reconstitution, immunoreconstitution and GVHD were studied by survival rate, peripheral blood counts, histological analysis and FACS at day +30 after transplantation. Immune function recovery were assessed by lymphocyte proliferation reaction stimulated with ConA and LPS and allogeneic mixed-lymphocyte reaction. At day 30 postransplant, compared with BMT groups, we observed that cotransplantation of MSC and bone marrow promoted the recovery of peripheral blood white blood cells (5.47±1.11x109/L vs7.12±1.70x109/L, p<0.05), lymphocytes and platelets. Accordingly, it was noticed that cotransplantation of MSC with BM not only improved recovery of bone marrow cellularity, but also enhanced B lymphopoiesis (4.66±1.03x109/L vs 6.05±1.39x109/L, p<0.05) and megakaryocytopoiesis (402.50±63.70 x109/L vs 594.33±121.09x109/L, p<0.05). MSC was also shown to improve thymic and spenic architecture reconstitution. Histological analysis showed that near normal thymus architecture and normal spenic architecture, with well-developed red and white pulp and intact lymphoid follicles in the cotransplantation group, while loss of demarcation between cortex and medulla in the thymus and lymphocytic depletion of spenic arteriolar sheaths in BM transplantation rats.The total number of thymus cells and spleen cells were also increased in cotransplantation group compared to only BM transplantation group. Most notable, the higher percentage of CD3+CD4+ was observed in the spleens of cotransplantation group (11.47±3.68% vs 19.14±4.03%, respectively), while no difference in the percentage of CD3+CD8+ between two groups (10.61±3.37% vs 12.13±2.27%, respectively). So the ratio of CD4+/CD8+ cells increased and inclined to normal in cotransplantation groups compared to only BM transplantation group.There are no difference in the percentage of natural killer (NK) cells and monocytes between BMT group and BMT with MSC group. The immuno-inhibitory effect of MSC on reducing GVHD in recipients of an MHC-mismatched BMT was also evident in our study, nonetheless, splenic cells from recipients of MSC cotransplantation group displayed improved non-specific proliferation capability (against ConA LPS stimulation) and alloreactivity (against the third party splenocytes) compared to BM transplantation group. In conclusion, rat bone marrow mesenchymal stem cells cotransplanted with BM improves hematopietic reconstitution and immunoreconstitution with alleviating graft-versus-host disease.

Absence of Inducible Costimulator (ICOS) on Alloreactive T Cells Reduces Graft-versus-Host-Disease While Leaving Graft-Versus-Tumor Activity Intact.

Inducible costimulator (ICOS) is a member of the B7 family that is expressed on activated and memory T cells and is involved in the regulation of TH1 and TH2 effector cytokine production after CD3/TCR stimulation. Studies with ICOS inhibition or ICOS−/− recipients have demonstrated prolonged allograft survival after heart or liver transplantation in animal models. To study the role of ICOS expression on alloreactive T cells in graft-versus-host disease (GVHD), we used allogeneic MHC class I and II disparate hematopoietic stem cell transplantation (allo-HSCT) models. We first analyzed the expression of ICOS by transferring CFSE-labeled donor T cells into irradiated allogeneic recipients and observed an increased expression of ICOS on alloreactive T cells compared to non-alloreactive T cells. We then studied B6-ICOS−/− alloreactive T cells and found intact proliferation in vivo (as determined by adoptive transfer of CFSE labeled T cells and donor T cell numbers in the spleen of allo-HSCT recipients), intact cytotoxicity, intact up regulation of activation markers, but decreased IFN-γ production in vitro. We then performed GVHD experiments in two models with full MHC class I and II disparity and observed significantly less GVHD morbidity and mortality in recipients of ICOS−/− donor T cells. Furthermore, histopathological analysis demonstrated less GVHD in all target organs (skin, liver, small bowel and large bowel) of recipients of ICOS−/− splenic T cells compared to recipients of wild type T cells. We harvested target organs (spleen, thymus, liver and gut) on days 7, 14, and 21 to examine donor T cell content (naïve and activated T cells) and found no significant difference in the total T cell numbers and subpopulations. Interestingly, in GVHD/graft-versus-tumor (GVT) experiments, ICOS−/− donor T cells displayed intact GVT activity, while their GVH activity was diminished. We then tested the levels of IFN-γ in the sera of mice undergoing GVHD and observed decreased serum levels in recipients of B6-ICOS−/− T cells. In conclusion, alloreactive ICOS−/− donor T cells display less GVHD morbidity and mortality due to decreased IFN-γ production, while proliferation, infiltration and GVT activity remain intact. These data suggests that strategies to inhibit ICOS could be useful for the prevention and/or treatment of GVHD in recipients of an allo-HSCT.

Absence of inducible costimulator on alloreactive T cells reduces graft-versus-host-disease while leaving graft-versus-tumor activity intact

Inducible costimulator (ICOS) has been recognized as a costimulatory molecule essential in T cell activation. Studies with ICOS inhibition or ICOS−/− recipients have demonstrated prolonged allograft survival after heart or liver transplantation in animal models. We hypothesized that inhibition of ICOS on alloreactive T cells would ameliorate the development of graft-versus-host-disease (GVHD) in recipients of an allogeneic bone marrow transplantation (allo-BMT). To analyze the expression of ICOS on donor T cells, we transferred CFSE-labeled donor T cells into irradiated allogeneic recipients and observed an increased expression of ICOS on alloreactive T cells compared to non-alloreactive T cells. We then performed GVHD experiments in two models with full MHC class I and II disparity and observed significantly less GVHD morbidity and mortality in recipients of ICOS−/− donor T cells. Interestingly, in GVHD/graft-versus-tumor (GVT) experiments, ICOS−/− donor T cells displayed intact GVT activity, while their GVH activity was diminished. We are currently performing experiments to assess the alloreactivity of ICOS−/− T cells in vivo, the infiltration of ICOS−/− donor T cells into GVHD target organs, and the degree of GVHD damage in target organs by histopathological analysis. In conclusion, we have found that ICOS−/− donor T cells cause less GVHD morbidity and mortality in comparison to wild-type donor T cells while preserving GVT activity. This data suggests that strategies to inhibit ICOS could be useful for the prevention and/or treatment of GVHD in recipients of an allo-BMT.

Administration of interleukin-7 after allogeneic bone marrow transplantation improves immune reconstitution without aggravating graft-versus-host disease

Prolonged immunodeficiency after allogeneic bone marrow transplantation (BMT) causes significant morbidity and mortality from infection. This study examined in murine models the effects of interleukin-7 (IL-7) given to young and middle-aged (9-month-old) recipients of major histocompatibility complex (MHC)-matched or -mismatched allogeneic BMT. Although administration of IL-7 from day 0 to 14 after syngeneic BMT promoted lymphoid reconstitution, this regimen was ineffective after allogeneic BMT. However, IL-7 administration from day 14 (or 21) to 27 after allogeneic BMT accelerated restoration of the major lymphoid cell populations even in middle-aged recipients. This regimen significantly expanded donor-derived thymocytes and peripheral T cells, B-lineage cells in bone marrow and spleen, splenic natural killer (NK) cells, NK T cells, and monocytes and macrophages. Interestingly, although recipients treated with IL-7 had significant increases in CD4(+) and CD8(+) memory T-cell populations, increases in naive T cells were less profound. Most notable, however, were the observations that IL-7 treatment did not exacerbate graft-versus-host disease (GVHD) in recipients of an MHC-matched BMT, and would ameliorate GVHD in recipients of a MHC-mismatched BMT. Nonetheless, graft-versus-leukemia (GVL) activity (measured against 32Dp210 leukemia) remained intact. Although activated and memory CD4(+) and CD8(+) T cells normally express high levels of IL-7 receptor (IL-7R, CD127), activated and memory alloreactive donor-derived T cells from recipients of allogeneic BMT expressed little IL-7R. This might explain the failure of IL-7 administration to exacerbate GVHD. In conclusion, posttransplant IL-7 administration to recipients of an allogeneic BMT enhances lymphoid reconstitution without aggravating GVHD while preserving GVL.

Genetic factors influencing the development of chronic graft-versus-host disease in a murine model.

Graft-versus-host disease (GVHD) is a major complication of bone marrow transplantation that can occur in either acute or chronic forms. Much of the long-term pathology seen in chronic GVHD is a result of autoantibody production. In the DBA/2-->B6D2F1 murine model of chronic GVHD, anti-ssDNA autoantibodies can be detected by 14 days post cell transfer. These autoantibodies are not observed in B6D2F1 recipients of cells from C57BL/6 or B10.D2 donors, which develop acute rather than chronic GVHD. Therefore, in this model, donor genetic factors predispose to the development of chronic GVHD in recipients. We performed a genetic analysis aimed at mapping donor loci that influence the magnitude of early autoantibody production in B6D2F1 recipients of cells from DBA/2 donor mice. Linkage analysis suggested an influence of two loci: a locus on chromosome 11 linked to D11Mit278 and a locus on chromosome 4 linked to D4Mit226. The locus on chromosome 11 also appeared to influence the development of renal pathology associated with chronic GVHD.

Composite Tissue Allografts in Rats: IV. Graftversus-Host Disease in Recipients of Vascularized Bone Marrow Transplants

This laboratory has used a composite tissue allograft model as a vehicle for studies on a new type of bone marrow transplant, the vascularized bone marrow transplant. The model consists of a rat hind limb transplant that incorporates integumentary musculoskeletal, and lymphopoietic tissues. These transplants, in comparison with conventional marrow transplants, have the advantage of providing a syngeneic microenvironment and immediate engraftment of both mature and progenitor hemopoietic cells at the time of transplantation. The characteristics of graft-versus-host disease were studied in this model. Lewis X Brown Norway F1 (LBN RT-1(1+n)) rats received hind limbs from Lewis (LEW RT-1(1)) donors (n = 19). Animals were observed daily for signs of graft-versus-host disease. Necropsies were performed. A minority of animals developed lethal disease (7 of 19 recipients) and demonstrated cachexia with concomitant histopathologic changes of the disease. Acute and chronic groups emerged with distinct clinical courses, which are similar to other models of this disease. Recipients of vascularized bone marrow transplants (limb transplants) showed clinical and histopathologic changes of the disease. The transplants may be used as a model of graft-versus-host disease in humans. Most interestingly, the transplant has a lower incidence of disease compared with other methods of bone marrow transplantation and represents an alternative to conventional bone marrow transplantation, which deserves further exploration. It may be possible to develop a new technique for bone marrow transplantation based on this surgical approach. It is proposed that the transfer of vascularized blocks of bone/marrow into prospective recipients as opposed to cellular bone marrow transplants may be preferable.

The role of repeat transplantation of haemopoietic stem cells and adoptive immunotherapy in treatment of leukaemia relapsing following allogeneic transplantation.

The role of repeat transplantation of haemopoietic stem cells and adoptive immunotherapy in treatment of leukaemia relapsing following allogeneic transplantation.

Effect of T cell subset dose on outcome of T cell-depleted bone marrow transplantation.

T cell depletion using the murine monoclonal antibody (moAb) T10B9 is unique in that the T cell receptor (TCR)gamma delta bearing subset is relatively spared compared to the TCR alpha beta + subset. We evaluated the probabilities of engraftment, acute and chronic graft-versus-host disease (GVHD), relapse, and survival in 273 recipients of marrow T cell depleted using T10B9. Sixty-two patients received marrow from an HLA-identical sibling, 54 patients received partially matched related donor marrow and 157 patients received unrelated donor marrow. Limiting dilution analysis (LDA) was used to estimate total clonable T cell dose in all patients and a modified LDA using moAb-coated immunomagnetic beads was used to estimate TCR alpha beta +, CD4+, and CD8+ T cells in a subset of patients. TCR gamma delta + cell dose was estimated by flow cytometry. Cox proportional hazards regression models were used to assess the impact of T cell subset dose/kg of body weight on outcome. We found a significant association of TCR gamma delta + T cell dose (P = 0.004), but not TCR alpha beta + T cell dose or total clonable T cell dose, with the probability of engraftment. TCR alpha beta +, CD4+, CD8+ and total clonable T cell dose were significantly associated (P < 0.001) with the risks of grade 2-4 acute GVHD in recipients of marrow from related donors but not in recipients of marrow from unrelated donors. Neither total clonable T cell dose nor any T cell subset dose was found to be significantly associated with chronic GVHD, relapse or survival. The results confirm preclinical studies showing TCR gamma delta + T cells promote engraftment. TCR gamma delta + T cells are not associated with an increased risk of acute GVHD while TCR alpha beta T cells are associated with acute GVHD but not engraftment in recipients of marrow grafts T cell depleted using T10B9. These findings support the hypothesis that T cell subsets differentially contribute to alloengraftment and GVHD.

Association of donor-derived host-reactive cytolytic and helper T cells with outcome following alternative donor T cell-depleted bone marrow transplantation.

Recipients of marrow from alternative donors (unrelated or HLA-mismatched related donors) have a higher incidence of post-transplant complications compared to recipients of marrow from HLA-identical siblings. HLA disparity undetected by routine typing techniques has been suggested as one cause for the increased complications observed. Limiting dilution analysis (LDA) of donor-derived, host-reactive T cell precursor frequency prior to transplant has been proposed as a surrogate indicator of underlying HLA disparity which might be used to predict transplant outcome and aid in donor selection. We compared results of LDA of host-reactive IL-2 producing helper T lymphocytes (HTLp) and/or cytolytic T lymphocytes (CTLp) in 77 alternative marrow donor/recipient pairs with transplant outcome using univariate and multivariate analysis. All donor grafts were depleted ex vivo of mature T cells. Median patient age was 15 years (1-53). Donor selection was based on serologic typing for HLA class I and high resolution oligotyping for HLA-DRB1-DRB5, and HLA-DQB1. HLA-A and HLA-B locus antigens were retrospectively defined by one dimensional isoelectric focusing (IEF). Cox proportional hazards regression models were used to assess the impact of frequency and estimated cell dose of CTLp and HTLp on outcome. The CTLp assay was most sensitive to HLA-A and HLA-B locus disparity detected by serology or IEF. The HTLp assay detected class I disparity but was most strongly reactive in the presence of HLA-DRB1 disparity. Univariate analysis indicated a significant association of CTLp frequency and dose with severe (grades 3-4) acute graft-versus-host disease (GVHD), and of CTLp dose with chronic GVHD. Both assays were associated with survival and neither assay was associated with relapse. After adjustment for other significant covariables including known HLA disparity, the association of CTLp with acute GVHD was lost, however, CTLp frequency and CTLp dose remained associated with survival and HTLp frequency was associated with chronic GVHD. These data support the hypothesis that post-BMT complications may be influenced not only by T cell dose but by the alloreactive potential of the cells infused. LDA of alloreactive potential was useful in detecting disparity and in predicting survival or chronic GVHD in recipients of alternative donor TCD marrow grafts.

Unrelated volunteer bone marrow transplantation: initial experience at St Vincent's Hospital, Sydney

Only 30% of patients with leukaemia have an HLA-compatible family member able to act as a marrow donor. The recent development of volunteer bone marrow donor registries has supplied HLA-matched donors for a number of such individuals. To define the problem and outcome of the first cohort of patients given HLA-matched unrelated volunteer bone marrow transplants at St Vincent's Hospital, Sydney. Post transplant outcome of patients with advanced leukaemia given HLA-identical unrelated donor marrow transplants was compared to that of patients transplanted concurrently from HLA-identical sibling donors, in terms of survival, leukaemia-free survival, incidence and severity of acute graft-versus-host disease (GVHD), duration of neutropenia, incidence of infection and duration of transplant hospitalisation. Sixteen patients with advanced leukaemia and without a histocompatible family member donor received unrelated donor bone marrow transplants. Actuarial survival at two years post transplant was 30%. Actuarial survival of 23 recipients of HLA-identical sibling bone marrow transplants with advanced leukaemia transplanted during the same time period was 17% (not significant). Actuarial disease free survival at two years was 30% and 13% respectively. Three of five long term survivors of the unrelated transplants had chronic myeloid leukaemia in blastic transformation at the time of transplant; thus blastic transformation should not preclude consideration of unrelated marrow transplantation. Recipients of unrelated allografts had a higher incidence of acute GVHD which occurred earlier and with greater severity than in recipients of sibling allografts, a longer duration of post transplant neutropenia (24 days to reach 0.5 x 10(9)/L versus 19.5, p = 0.07), a higher frequency of infection in the first 100 days post transplant (p = 0.0004) and a longer duration of transplant hospitalisation (p = 0.04). Transplant-related complications were the commonest cause of death in the unrelated donor recipients, while leukaemic recurrence was the commonest single cause of death in the HLA-identical sibling recipients. Improvements are needed in prophylaxis of infection and in prevention and treatment of acute GVHD in recipients of unrelated donor transplants. Nevertheless, this modality provides curative treatment for patients with otherwise incurable haematological malignancies and should no longer be considered experimental.

Induction of cutaneous graft-versus-host disease by administration of cyclosporine to patients undergoing autologous bone marrow transplantation for acute myeloid leukemia [see comments

Cutaneous graft-versus-host disease (GVHD) has been reported after administration of cyclosporine (CSP) after autologous bone marrow transplantation (ABMT) with unpurged marrow in patients with lymphoma. To determine whether GVHD can be induced after ABMT with chemopurged marrow in acute myeloid leukemia (AML), we administered intravenous CSP for 28 days (beginning on the day of ABMT) to 19 patients with AML (12 in first remission [CR1], six in CR2, and one in CR3) who received busulfan (16 mg/kg) and cyclophosphamide (200 mg/kg) and ABMT with 4- hydroperoxycyclophosphamide (4HC)-treated marrow. In this dose- escalation trial, CSP daily doses were 1 mg/kg in seven patients, 2.5 mg/kg in eight patients, or 3.75 mg/kg in four patients. Skin biopsies were obtained weekly after ABMT or on appearance of rash and were graded for GVH changes. Overall, 15 of 19 patients (79%) had cutaneous histopathologic grade 2 GVHD at a median of 33 days (range, 14 to 49) after ABMT; in 10, cutaneous manifestations were present at time of positive biopsy. The frequency, time to onset, and duration of GVHD were similar among the three CSP dosage groups. No patients had hepatic or gastrointestinal dysfunction attributable to GVHD or required specific therapy for GVHD. Positive biopsies for GVHD were seen in seven of eight patients who received full-course, full-dose CSP and 8 of 11 patients who had CSP discontinued or dosage reduced because of renal insufficiency. Three patients (one with positive biopsy) died with ABMT-related complications. Seven patients (four CR1, three CR2) relapsed with AML at a median of 411 days (range, 178 to 549) after ABMT; six of seven had positive biopsies for cutaneous GVHD. Nine patients (seven CR1, one CR2, and one CR3) are alive without relapse at a median of 501+ days (range, 252+ to 811+) after ABMT; eight of nine had cutaneous GVHD. Short-course CSP can induce autologous GVHD in recipients of chemopurged marrow autografts for AML, but randomized prospective trials are needed to determine whether this immunologic reaction is associated with alterations in leukemic relapse rate and disease-free survival after ABMT in AML.

Induction of Cutaneous Graft-Versus-Host Disease by Administration of Cyclosporine to Patients Undergoing Autologous Bone Marrow Transplantation for Acute Myeloid Leukemia

AbstractCutaneous graft-versus-host disease (GVHD) has been reported after administration of cyclosporine (CSP) after autologous bone marrow transplantation (ABMT) with unpurged marrow in patients with lymphoma. To determine whether GVHD can be induced after ABMT with chemopurged marrow in acute myeloid leukemia (AML), we administered intravenous CSP for 28 days (beginning on the day of ABMT) to 19 patients with AML (12 in first remission [CR1], six in CR2, and one in CR3) who received busulfan (16 mg/kg) and cyclophosphamide (200 mg/kg) and ABMT with 4-hydroper-oxycyclophosphamide (4HC)-treated marrow. In this dose-escalation trial, CSP daily doses were 1 mg/kg in seven patients, 2.5 mg/kg in eight patients, or 3.75 mg/kg in four patients. Skin biopsies were obtained weekly after ABMT or on appearance of rash and were graded for GVH changes. Overall, 15 of 19 patients (79%) had cutaneous histopathologic grade 2 GVHD at a median of 33 days (range, 14 to 49) after ABMT; in 10, cutaneous manifestations were present at time of positive biopsy. The frequency, time to onset, and duration of GVHD were similar among the three CSP dosage groups. No patients had hepatic or gastrointestinal dysfunction attributable to GVHD or required specific therapy for GVHD. Positive biopsies for GVHD were seen in seven of eight patients who received full-course, full-dose CSP and 8 of 11 patients who had CSP discontinued or dosage reduced because of renal insufficiency. Three patients (one with positive biopsy) died with ABMT-related complications. Seven patients (four CR1, three CR2) relapsed with AML at a median of 411 days (range, 178 to 549) after ABMT; six of seven had positive biopsies for cutaneous GVHD. Nine patients (seven CR1, one CR2, and one CR3) are alive without relapse at a median of 501+ days (range, 252+ to 811+) after ABMT; eight of nine had cutaneous GVHD. Short-course CSP can induce autologous GVHD in recipients of chemopurged marrow autografts for AML, but randomized prospective trials are needed to determine whether this immunologic reaction is associated with alterations in leukemic relapse rate and disease-free survival after ABMT in AML.

ABO compatibility and acute graft-versus-host disease following allogeneic bone marrow transplantation.

If ABO antigens/antibodies play any role in the pathogenesis of acute graft-versus-host disease (GVHD), one would expect the highest incidence of GVHD in recipients of minor ABO-mismatched grafts, followed by ABO-matched grafts, and the lowest incidence in major ABO-mismatched transplants. To test this hypothesis 174 patients receiving an HLA-identical allogeneic bone marrow transplant (BMT) for aplastic anemia (n = 32) or leukemia (n = 142) were analyzed for factors associated with acute GVHD. Variables analyzed included diagnosis, sex, age, blood group of donor and recipient, ABO compatibility, Rhesus compatibility, sex compatibility, number of bone marrow cells given at BMT, year of transplant, day of engraftment, and GVHD prophylaxis. We first carried out an exploratory contingency table analysis: minor ABO incompatibility was associated with a significantly higher risk of severe acute GVHD when compared with ABO-matched and major-ABO mismatched pairs (P = 0.003): 14/9, 57/67, and 5/22 patients developed, respectively, 0-I/II-IV acute GVHD in ABO major-mismatched, matched, and minor-mismatched pairs. Donors of group 0, (P = 0.06), older recipient's age (P = 0.08), fast engraftment (P = 0.03), and older donor's age (0.08) were also associated with a higher risk of GVHD. Recipient's ABO group, diagnosis, year of transplant, Rhesus group of donor or recipient, Rhesus compatibility, sex of donor or recipient, sex compatibility, and type of GVHD prophylaxis were not predictive of GVHD. A Cox multifactorial proportional hazards analysis confirmed that ABO matching was the single most significant factor associated with GVHD (P = 0.006). The cumulative incidence of GVHD grade II+ was 39%, 54%, and 82% for ABO major-mismatched, matched, and minor-mismatched pairs (P = 0.01). This study suggests that ABO antigens may play a role in the development of acute GVHD.

A COMPARATIVE TRIAL OF POSTTRANSPLANT IMMUNOSUPPRESSION IN PATIENTS TRANSPLANTED FOR THALASSEMIA

This study compares the efficacy of 2 posttransplant immunosuppressive regimens for prevention of graft-versus-host disease (GVHD). Forty-four patients, ages 8-15 years, with homozygous beta thalassemia received marrow allografts from HLA-identical siblings following an ablative regimen of busulfan and cyclophosphamide. Twenty-two patients received cyclosporine (CsA) alone and 22 received cyclosporine, cyclophosphamide, and methotrexate for prophylaxis against GVHD. Two who received CsA alone have died (1 of graft rejection and 1 of acute GVHD) as did 4 patients who received 3 drugs (1 of rejection, 1 of acute GVHD, 1 of infection and cardiac failure before engraftment, and 1 of acute respiratory failure before engraftment). One patient in each group rejected the transplant and survives with thalassemia. The probability of developing acute GVHD was 41% for the CsA group and 15% for the 3-drug group (P = less than 0.05). Patients receiving CsA alone had a probability of event-free survival of 86% compared to 77% in the group receiving 3 drugs (P = 0.40) with a followup of 209-706 days. Although the study showed a decrease in the incidence of GVHD in recipients of the more intensive prophylactic regimen, this study was terminated since it was apparent that even if larger numbers of patients were studied it would be difficult to demonstrate a significant survival advantage with the use of this drug regimen.

Alternatives to donor matching for control of graft-versus-host disease.

Graft-versus-host disease (GvHD) after bone-marrow transplantation in dogs is controlled by many different genetic systems. In littermate combinations identical for the major histocompatibility complex (MHC) the number of systems that influence GvHD is related to the number of donor lymphocytes injected. If the number of donor lymphocytes administered is sufficiently low, minor histocompatibility systems do not influence survival after bone-marrow transplantation. With increasing numbers of donor lymphocytes the beneficial influence of MHC matching on GvH incidence and severity disappears and minor histocompatibility antigens, coded for on at least two other autosomal chromosomes as well as possibly the Y chromosome, can cause severe GvHD. In contrast, the X chromosome does not appear to carry a histocompatibility system that is of relevance to GvHD control. The severity and tissue distribution of histological signs of GvHD in recipients of bone-marrow and lymph-node cells from MHC-identical donors are similar to those in recipients of MHC-mismatched bone-marrow cells. Female donors do appear to cause severe GvHD more frequently than males. In contrast to rhesus monkey and human bone-marrow cells, dog bone-marrow cells are negative in PHA tests. This is in accordance with the generally benign course of GvHD in dogs that are treated with bone-marrow cells only from histocompatible littermate donors. The influence of the sex of the bone-marrow donor on GvHD incidence and severity is not reflected in differences between PHA tests with male and female dog lymphocytes. A better predictive test for GvH potential than the PHA test appears to be needed. Alternatives to additional donor selection for the prevention of GvHD in histocompatible recipients appear to be the use of a male donor and the removal of lymphocytes from bone-marrow-cell suspensions prior to transplantation.