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Chronic rejection (CR) is a major problem in long-term survival in heart transplantation. We analysed whether the occurrence of CR correlates with the incidence of acute rejections (AR) or with characteristics of endomyocardial biopsy-derived cell cultures. CR was diagnosed by annual angiography and defined as all coronary vascular changes. One year after transplantation 24 of the 63 patients had CR (38%). The incidence of AR in CR + and CR — patients was comparable. The patients in both groups had similar individual median percentages of EMB-yielding cell cultures. During the first year the CR — patients had more cultures in which at least 60% of the cells were CD4 + T cells (50% vs 37%, P = 0.05), due to a stronger CD4 predominance in the first 6 months. In the second year the CD4 predominance in the patients diagnosed as CR + after 1 year tended to be higher (P = 0.08). The patients had comparable percentages of cultures predominated by CD8 + T cells, γδ T cells or NK cells, irrespective of the time interval. These results might indicate that CD4 + T lymphocytes play a dual role in the aetiology of CR.  相似文献   
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Abstract BT563, a murine anti-IL-2R MoAb, was found to be more potent than anti-Tac in inhibiting proliferation in the mixed lymphocyte reaction. Results obtained with 33 B3.1 in these experiments were similar to those with BT563. The anti-IL-2R MoAb 2A3 was shown to be a suitable agent for monitoring the effect of BT563 on peripheral blood. IL-2R-positive cells were not detected in peripheral blood samples from 1 h after the first dose until 8 days after the last dose. Plasma trough levels were measured in patients receiving 5 or 10 mg daily. The administration of BT563 to allograft recipients did not lead to clinically significant side effects.  相似文献   
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BACKGROUND. Lymphomatoid papulosis is a benign cutaneous eruption that in 10 to 20 percent of patients is associated with the development of lymphoma. The atypical cells of lymphomatoid papulosis histologically resemble the malignant cells of cutaneous T-cell lymphoma or the Reed-Sternberg cells of Hodgkin's disease. We studied a patient in whom lymphomatoid papulosis developed in 1971, Hodgkin's disease in 1975, and cutaneous T-cell lymphoma in 1985, to determine whether these diseases are clonally related. METHODS. The T-cell-receptor alpha-chain gene was cloned and sequenced from a cell line derived from the advanced-stage cutaneous T-cell lymphoma, and the polymerase chain reaction was used to search for this rearrangement of the alpha-chain gene in tissues obtained earlier that were affected by Hodgkin's disease or lymphomatoid papulosis. RESULTS. The tumor-specific rearrangement of the alpha-chain gene was detected in the patient's earlier tissues affected by lymphomatoid papulosis and Hodgkin's disease, but not in control tissue, including uninvolved tissues from the staging laparotomy for Hodgkin's disease. Cytogenetic studies revealed a translocation, t(8;9)(p22;p24), in cutaneous T-cell lymphoma lines and in a dermatopathic lymph node removed two years before the clinical onset of the cutaneous T-cell lymphoma. Immunohistochemical findings were consistent with an activated T-cell phenotype for the atypical cells of lymphomatoid papulosis, the Reed-Sternberg cells of Hodgkin's disease, and the malignant cells of the T-cell lymphoma. CONCLUSIONS. Lymphomatoid papulosis, Hodgkin's disease, and cutaneous T-cell lymphoma can be derived from a single T-cell clone. A t(8;9) genetic translocation may be involved in the pathogenesis of lymphomatoid papulosis or its progression to malignant disease.  相似文献   
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Human intestinal intraepithelial lymphocytes (DEL) are a uniquepopulation of predominantly CD8ß+ TCRß+lymphocytes and, to a lesser extent, TCR+ lymphocytes that proliferatepoorly to anti-CD3 mitogenic signals but display significantcytolytic activity. Studies in mouse model systems have shownthat the chain of the high-CD3 affinity receptor for IgE (FcRl)may substitute for the chain in the TCR-CD3 complex of iIEL.This has suggested that the functional properties of these cellsmay be associated with an altered composition of the TCR-CD3complex. We therefore analyzed the TCR-CD3 complex of normalhuman iIEL. One-and two-dimensional non-reducing/reducing SDS-PAGEanalysis of CD3, CD3, CD3, and FcRr chain immunopreclpitatesof cell surface radiolabeled proteins with subunit-specificantibodies revealed a TCR-CD3 complex without associated FcRrchains. Thus, normal human NEL contain a TCR-CD3 complex thatconsists predominantly of , homodimers in association with theß TCR and CD3, and , similar to the majority of peripherallymphocytes. This indicates that the distinct properties ofhuman DEL are not associated with substitutions of the FcRlchain in the TCR-CD3 complex.  相似文献   
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Cellular immune processes may trigger the development of graft vascular disease (GVD). CD4 and CD8 cytotoxic T lymphocytes that infiltrate the allograft could play a role in the development of GVD. We studied the presence of in vivo primed or committed CTL (cCTL) and their avidity for donor HLA class I and class II antigens in graft-infiltrating lymphocyte cultures propagated from endomyocardial biopsies derived from patients with and without signs of GVD. The fraction of cCTL with high avidity for HLA class I or class II antigens was estimated by the addition of anti-CD8 or anti-CD4 MoAbs to the cytotoxic phase of the limiting dilution analysis. In the first year after transplantation no difference in the frequency of donor-specific class I cCTL between patients with and without GVD was found. Addition of anti-CD8 MoAb revealed that most cultures predominantly consisted of cCTL with low avidity for donor HLA class I antigens, irrespective of the development of GVD at 1 year after transplantation. However, in patients who did not develop GVD, the frequency of cCTL with donor HLA class II specificity was significantly higher than in patients who did develop GVD. The avidity for donor HLA class II antigens was comparable in both groups. A high frequency of donor-specific cCTL for HLA class II antigens seems to be a protective factor against the development of GVD. These cCTL might be cytotoxic for cells involved in GVD development, e.g. activated endothelium and smooth muscle cells of donor origin.  相似文献   
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In order to better understand the role of intestinal CD1d, we sought to define the cellular localization and further characterize the biochemical structure of CD1d in human intestinal epithelial cells (IEC). Using a CD1d-specific rabbit anti-gst-CD1d antibody, immunoprecipitation of radiolabeled cell surface proteins detected a previously identified 37 kDa protein as well as a 48-50 kDa protein which were confirmed by Western blotting with a CD1d-specific mAb, D5. Immunoprecipitation of protein lysates with the CD1d-specific mAb, D5 and 51.1.3, and the beta2-microglobulin (beta2m)-specific mAb, BBM.1, followed by N-glycanase digestion and Western blotting with the D5 mAb showed that the 48-50 kDa protein was a beta2m-associated, CD1d glycoprotein. CD1d was immunolocalized to the apical and lateral regions of native small and large intestinal IEC as defined by confocal laser microscopy using the D5 mAb and the rabbit anti-gst-CD1d antibody. In addition, a large apical intracellular pool of CD1d was identified. Identical observations were made with polarized T84 cells. Selective biotin labeling of apical and basolateral cell surfaces followed by immunoprecipitation with the D5 mAb, N-glycanase digestion and avidin blotting confirmed the presence of glycosylated CD1d on both cell surfaces and immunolocalization of the 37 kDa non-glycosylated form of CD1d to the apical cell surface. These studies show that CD1d is located in an ideal position for luminal antigen sampling and presentation to subjacent intraepithelial lymphocytes.  相似文献   
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