Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0018133 (graft-versus-host disease)
 18,032 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Immune recognition of foreign HLA molecules is initiated by T cell recognition mediated by alloreactive T cell receptor (TCR) molecules. We analyzed the diversity of TCR expression in the clinical setting of allorecognition in a patient with acute graft-versus-host disease following bone marrow transplantation. Nearly 200 TCR transcripts from peripheral blood lymphocytes were cloned and sequenced at two time points during GVHD. HLA genes in the transplant donor and the recipient were mismatched for a very specific HLA-DR subtype: HLA-DRB1 genes in the donor (DR4/Dw4) and the recipient (DR4/Dw14) encode HLA molecules that differ at only two amino acids, providing a very restricted target for allorecognition. We also studied TCR genes from five T cell clones derived in vitro from mixed lymphocyte cultures between Dw4-positive responder and Dw14-positive stimulator cells. Comparisons of the derived TCR sequences implicate nonrandom patterns of TCR selection both in vivo and in vitro.
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PMID:Selective T-cell-receptor gene usage in allorecognition and graft-versus-host disease. 768 37

Administration of cyclosporine (CsA) following syngeneic/autologous bone marrow transplantation (BMT) elicits a T lymphocyte-dependent autoimmune disease resembling graft-vs-host disease (syngeneic GVHD). This autoaggression syndrome appears to be due to the autorecognition of self-MHC class II antigens by CD8+ cytolytic T cells and a CD4+ autoreactive T cell subset. The syngeneic GVHD model was used to assess the effectiveness of treatment with monoclonal antibodies to the alpha/beta T cell receptor (TCR) and the CD4 or CD8 determinants on the prevention of autoimmune disease. Nylon wool nonadherent splenic T cells (50 x 10(6)) from Lewis strain rats with active syngeneic GVHD were adoptively transferred into irradiated (1050 rad syngeneic recipients reconstituted with normal marrow (60 x 10(6) cells). Monoclonal antibody (McAb) to the alpha/beta TCR, the CD4 determinant, or the CD8 determinant was administered to secondary recipients on Days 0, 3, 6, 9, and 12 at a dose of 0.1 ml of ascites fluid. Control animals received normal mouse serum on the same schedule. Animals treated with either saline or normal mouse serum developed syngeneic GVHD within 16-20 days. Comparatively, syngeneic GVHD developed much later in the secondary recipients treated with anti-CD4 McAb (onset of syngeneic GVHD, 28-32 days) and was less severe compared to the control group. On the other hand, the recipients treated with McAb's to the alpha/beta TCR or to the CD8 determinant did not develop syngeneic GVHD (monitored over 10 weeks post-therapy). Peripheral blood lymphocytes from these recipients also were analyzed for T cell subsets by phenotypic analysis. There was a pronounced reduction of the total number of cells expressing the alpha/beta TCR and the CD8 determinant after treatment of the recipients with the McAb's to the alpha/beta TCR and to the CD8 determinant, respectively. Recovery to normal levels began to occur 6 weeks after the last dose of McAb. There was a significant reduction of the CD4+ subset after treatment with anti-CD4 McAb, but it was not long lasting with recovery coinciding with the onset of syngeneic GVHD. Studies were also performed to evaluate McAb therapy of established syngeneic GVHD. The McAb's were found to be largely ineffective due in part to pulmonary toxicity. Furthermore, this model was utilized to evaluate the efficacy of treatment with McAb to the target antigen of syngeneic GVHD. Infusion of McAb to a public determinant on class II MHC molecules prevented or significantly delayed the onset of syngeneic GVHD after adoptive transfer of effector cells.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Cyclosporine-induced syngeneic graft-vs-host disease: prevention of autoaggression by treatment with monoclonal antibodies to T lymphocyte cell surface determinants and to MHC class II antigens. 769 18

Allogeneic bone marrow transplantation has become the therapy of choice in many cases of hematologic malignancy. In both matched related donor transplants--and, to a greater degree, in unrelated donor transplant situations--a major complication of the procedure is GVHD. This problem is caused by mature T cells in the graft, which also facilitate engraftment, and mediate an antitumor effect to reduce relapse. In order to further characterize the T cells that are present at the GVHD site of injury, we have studied 134 fresh tissue biopsies using immunohistochemical methods from 50 consecutive ABMT recipients clinically suspected of having acute GVHD. Antibodies specific for T cells, T cell receptor subsets, B cells, and NK cells were used to characterize the lymphocytic infiltrate in the biopsy tissue from GVHD patients. The data showed that the majority of lymphocytes that had infiltrated the epithelium or epidermis were CD3+ T cells. Using antibodies that distinguished the alpha/beta (beta F1) from the gamma/delta TCR (TCR delta 1)-expressing T cells, we observed that the lymphocytic infiltrates from involved tissues of the gastrointestinal tract, skin, and liver are almost exclusively derived from the alpha/beta expressing T cell subset, and are of the memory cell subset of T cells (CD45RO). This is in contrast to some examples from other disease states, in which a significant proportion of the lymphocytes that infiltrate the epidermal layers are of the gamma/delta type.
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PMID:Immunohistochemical analysis of T cell phenotypes in patients with graft-versus-host disease following allogeneic bone marrow transplantation. 777 Sep 32

We reported that T cell receptor (TcR) gamma delta intestinal intraepithelial lymphocytes (i-IEL) of host origin increased transiently, then decreased drastically at the early stage of non-irradiated acute graft-versus-host disease (GVHD) in mice. We investigated the role of the TcR gamma delta i-IEL of host origin in the pathogenesis of the intestinal lesions that occur during acute GVHD. The acute GVHD was induced in mice which had been depleted of TcR gamma delta by in vivo administration of hamster monoclonal antibody (mAb) against TcR gamma delta. Although the degree of splenomegaly after the induction of acute GVHD in mice treated with anti-TcR gamma delta mAb was similar to that in control mice treated with hamster anti-2,4,6-trinitrophenyl mAb, infiltration of donor-derived T cells into the epithelium, and mitosis and apoptosis of crypt cells in the intestinal mucosa were dramatically suppressed in these mice. This suggest that host TcR gamma delta T cells in i-IEL contribute to the development of enteropathy in acute GVHD in mice.
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PMID:Host intestinal intraepithelial gamma delta T lymphocytes present during acute graft-versus-host disease in mice may contribute to the development of enteropathy. 784 57

We examined the kinetics of intestinal intraepithelial lymphocytes (IEL) and the incidence of apoptosis at villus or crypt sites during the development of non-irradiated acute graft-versus-host disease (GVHD). The first IEL to increase were host-origin on day 3 and the donor-derived IEL appeared first on day 12 after GVHD induction. Unique CD3+CD4+CD8 alpha/alpha+ IEL were significantly increased on day 6 and an appreciable number of IEL bearing T cell receptor V beta capable of recognizing self-superantigen were detected on day 9. The sudden appearance of apoptosis and reduction of mitotic activity occurred on day 12, accompanied by a dramatic decrease of CD3+CD4-CD8 alpha/alpha+ IEL of host origin. CD8 alpha/alpha+ IEL of host origin, which expand and then decrease by apoptosis at the early stage of acute GVHD, may be associated with pathogenesis of the enteropathy occurring during acute GVHD.
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PMID:Kinetics of intestinal intraepithelial lymphocytes during acute graft-versus-host disease in mice. 790 97

When MRL/lpr (H-2k) spleen cells were intraperitoneally injected into C.B-17-scid/scid (severe combined immunodeficient (SCID)) (H-2d) mice, the SCID (SCID-MRL/lpr) mice manifested a severe wasting syndrome with weight loss, splenic atrophy, and lymphoid cell infiltration in the liver and lung, as seen in lpr-GVHD. In contrast, MRL/+ spleen cell-injected SCID (SCID-MRL/+) mice did not show lpr-GVHD. The spleens of SCID-MRL/lpr mice showed progressive increases in donor CD4+ and CD8+ T cells from 4 to 12 weeks after injection and a decrease in B cells at 12 weeks. SCID-MRL/+ mice showed a stable engraftment of CD4+ and CD8+ T cells and a progressive increase in B cells. Analyses of T cell receptor (TCR) repertoires (V beta 6, V beta 8.1,2 and V beta 11) revealed that the V beta 8.1,2+ T cells were found more frequently in SCID-MRL/lpr mice than in SCID-MRL/+ mice. When SCID-MRL/lpr mice were treated with intraperitoneal injection of an anti-V beta 8.1,2 (KJ16) MoAb, V beta 8.1,2+ T cells were markedly depleted, and the severity of lpr-GVHD was attenuated at 4 and 8 weeks after treatment, in contrast to normal rat IgG-injected SCID-MRL/lpr mice. However, the KJ16 MoAb-treated SCID-MRL/lpr mice suffered from severe lpr-GVHD 12 weeks after treatment, although V beta 8.1,2+ T cells were still maintained at a low level. These findings suggest that V beta 8.1,2+ T cells are a major T cell population that mediates lpr-GVHD in the early stage of lpr-GVHD, but that in the later stage, the other T cell populations may proliferate naturally or in accordance with the depletion of V beta 8.1,2+ T cells, and contribute to the development of lpr-GVHD.
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PMID:Attenuation of lpr-graft-versus-host disease (GVHD) in MRL/lpr spleen cell-injected SCID mice by in vivo treatment with anti-V beta 8.1,2 monoclonal antibody. 800 20

Following autologous bone marrow transplantation (ABMT), both impaired T cell activation and defective production of the principal T cell growth factor, interleukin-2 (IL-2), has been observed. These processes are dependent on a rise of intracellular calcium ([Ca2+]i), a step which follows binding of T cell receptor (TCR) and transduction of signal via the generation of cytoplasmic second messengers. In order to better understand the nature of defective cellular immunity in ABMT, in the present study we investigated the rise of [Ca2+]i in T cells of recipients of ABMT. By concomitant labelling lymphocytes with anti-CD4 antibody and addition of fluo-3 as fluorescent calcium indicator, we have selected for the T cell subset which is the principal source of IL-2. Short-term (less than 1 year post-transplantation) recipients of ABMT show a statistically significant blunted rise in [Ca2+]i in response to concanavalin A as compared to normal controls not accounted for solely by a decreased percentage of CD4+ cells in these patients. The [Ca2+]i response of CD4+ cells from long-term (greater than 1 year post-transplant) recipients was lower than that of the normal group although not to a statistically significant level. These findings suggest that following ABMT is a defect in the early stages of T cell activation involving either T cell receptor binding or early signal transduction ultimately resulting in depressed transcription of IL-2 mRNA. These defects are analogous to findings in both allogeneic transplantation where factors of histoincompatibility and graft-versus-host disease (GVHD) come into play, as well as in the defective T cell activation of the normal ageing process.
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PMID:Blunted rise in intracellular calcium in CD4+ T cells in response to mitogen following autologous bone marrow transplantation. 810 19

The graft-vs.-host reaction (GVHR) results in damage to the epithelial and lymphoid compartments of the thymus and thus in abnormal maturation and function of thymocytes in mice undergoing GVHR. In this report, the effects of GVHR on thymic T cell receptor (TCR) expression and usage have been investigated. GVHR was induced in unirradiated F1 hybrid mice by the intravenous transfer of parental lymphoid cells. Expression of the CD3/TCR complex on thymocyte subsets defined by CD4 and CD8 was studied by three-color flow cytometry. The level of CD3/TCR was decreased on CD4+CD8-, but not CD4-CD8+, mature thymocytes. The lack of upregulation of CD3/TCR on CD4 single-positive thymocytes, but not on their CD8+ counterparts, suggested an abnormality of class II major histocompatibility complex (MHC) expression in the thymuses of mice undergoing GVHR. Immunofluorescence staining of thymic frozen sections revealed that MHC class II expression was dramatically decreased in GVH-reactive mice. GVHR-induced changes in positive and negative selection were evaluated by determining the incidence of specific V beta TCR segment usage in the thymus. In normal mice, thymocyte usage of any given V beta segment was highly consistent between individuals of the same strain and age; however, a marked divergence in the incidence of TCR V beta 6hi and V beta 8hi cells between GVH-reactive littermate mice was observed, suggesting that thymic positive selection had become disregulated in these animals. Furthermore, negative selection was defective; the incidence of phenotypically self-reactive V beta 6hi T cells was significantly greater in the thymuses of GVH-reactive mice bearing the endogenous superantigen Mls-1a than in untreated controls. Thus, mice undergoing GVHR showed defective TCR upregulation on CD4+CD8- thymocytes and changes in TCR usage reflecting aberrant thymic selection, in conjunction with decreased expression of MHC class II. Most abnormalities of TCR expression and usage on CD4+ thymocytes observed in GVH-reactive mice were analogous to those of class II knockout mice.
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PMID:Thymic selection and thymic major histocompatibility complex class II expression are abnormal in mice undergoing graft-versus-host reactions. 839 4

We recently demonstrated that frequencies of T cell receptor-V (TcR-V)-specific subsets are frequently altered after both allogeneic and autologous BMT. The data reported here describe several characteristics of altered T cell subsets: (i) their capacity to endure peripherally, (ii) their correspondence to clonal donor T cell subsets, (iii) the origin of the clone (in one case amenable to analysis) from a mature T cell and not from new lymphopoiesis, and (iv) the presence of such a clone throughout a year of follow-up in a patient with chronic graft-versus-host disease (GVHD) in whom it represented up to 1/10th of CD3+ peripheral blood lymphocytes (PBL) and was found to be host-reactive. Taken together, these findings provide direct evidence for the oligoclonality of a large proportion of the peripheral T cell repertoire in patients subsequent to bone marrow transplantation, possibly accounting for their frequent depressed immune status. Moreover, the anti-host reactivity demonstrated in a clone from the patient with chronic GVHD strongly suggests that an oligoclonal response can be linked to a pathological process.
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PMID:Alterations of T cell repertoire after bone marrow transplantation: characterization of over-represented subsets. 853 16

Most patients requiring allogeneic bone marrow transplantation (BMT) lack a human leukocyte antigen genotypically identical sibling and require an alternative donor. This carries an increased risk of graft failure and acute graft-versus-host disease (GVHD). We sought to overcome these problems with transplants by using grafts obtained from the most readily available source: the haploidentical, partially mismatched, related donor. This study of 40 patients used a novel approach combining in vitro and in vivo T cell depletion with T lymphocyte targeted monoclonal antibodies (mAb) and intensified conditioning therapy, including fractionated total body irradiation before etoposide, cytoside arabinoside, cyclophosphamide, and methylprednisolone. Grafts were treated with T10B9.1A-31 mAb, directed against the alpha-beta heterodimer of the T cell receptor, and rabbit complement. In vivo depletion was attempted with an anti-CD5 mAb-Ricin A-chain (H65-RTA) immunotoxin (IT). Study patients were compared with a historical control group of 17 patients not given H65-RTA. Rates of engraftment were not significantly different (93% vs. 100%, P=0.12), although patients receiving IT engrafted more rapidly. The incidence of > grade I GVHD was significantly lower in the study group (36% vs. 100%, P=0.0001), as well as for severe grade III-IV GVHD (19% vs. 92%, P=0.0001). Five-year survival tended to be improved in the study group (40% vs. 18%, P=0.21). Transplant from haploidentical family members is indicated for patients without a matched sibling in whom allogeneic BMT offers the best opportunity to achieve cure.
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PMID:Combined in vitro and in vivo T lymphocyte depletion for the control of graft-versus-host disease following haploidentical marrow transplant. 860 77


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