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)

An immunohistological study of the distribution of three cellular adhesion molecules, ICAM-1, VCAM-1 and ELAM-1, was undertaken on normal liver and liver biopsies taken from allogeneic bone marrow transplant (BMT) recipients. In normal controls, ICAM-1 was seen on vascular endothelium and sinusoidal lining cells, and VCAM-1 on Kuppfer cells and dendritic macrophages in portal tracts. ELAM-1 staining was virtually absent. Biopsies from BMT recipients with histological evidence of hepatic graft-versus-host disease (GVHD) showed ICAM-1 expression on damaged bile duct epithelium in only one of five cases, in contrast to four of five showing epithelial HLA-DR expression. Increased numbers of VCAM-1 positive portal tract macrophages were seen in GVHD and also in non-GVHD pathology. No increase in vascular endothelial expression of VCAM-1 or ELAM-1 was seen. These findings contrast with previous studies on other target sites for GVHD, namely skin and gastrointestinal tract, where the expression of all three molecules is increased on various cells. Although the lack of adhesion molecule expression in the liver in GVHD in this study may be related to the timing of biopsies or immunosuppressive therapy, it is likely to represent to some extent variation in cell and molecular changes occurring in the different tissues affected by GVHD.
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PMID:Adhesion molecule expression in human hepatic graft-versus-host disease. 138 79

Depletion of Langerhans cells (LC) is known to follow bone marrow transplantation (BMT) and is thought to be mainly related to pretransplant radiation and chemotherapy conditioning regimens. We studied sequential biopsies of clinically normal skin of 22 thalassemic and leukemic patients undergoing allogeneic BMT who had received only chemotherapy (busulfan and cyclophosphamide) as conditioning regimen. LC were identified immunohistochemically using antibodies against CD1a and HLA-DR antigens, and their number expressed per square mm of epidermal vertical section, the latter measured by computerized image analysis. After the preparatory regimen, the number of LC decreased progressively in both leukemic and thalassemic patients. CD1a+ and HLA-DR+ epidermal cells were reduced, respectively, to 68.5% and 64.5% of their original number around Day 2, and to 23.1% and to 18.2% around Day 17. By this time, electron microscopic examination of selected biopsies confirmed the depletion of LC. Variable repopulation was observed between Days 40 and 60. Our results indicate that a conditioning regimen based exclusively on high dose chemotherapy depletes epidermal LC early after BMT, and that such depletion is not related to the development of acute graft-versus-host disease.
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PMID:Epidermal Langerhans cells after allogeneic bone marrow transplantation: depletion by chemotherapy conditioning regimen alone. 138 97

Previous studies demonstrated that the frequency of donor-versus-host-reactive cytotoxic T-cell precursors (CTL-p) before allogeneic bone marrow transplantation (BMT) from matched unrelated donors correlates with the incidence of graft-versus-host disease (GvH-D). We investigated whether clinical manifestations of GvH-D after HLA-identical sibling BMT are accompanied by an increased frequency of minor histocompatibility antigen (HA)-specific CTL-p. We further asked whether changes of third-party-reactive CTL-p as a measure of overall immunocompetence are related to infectious complications frequently seen immediately after BMT. Eighteen patients (16 with an HLA-identical bone marrow graft, two with either one HLA-A or one HLA-DR mismatch) were studied. Limiting dilution analysis (LDA) was used to assess donor CTL-p frequencies against recipient pre-BMT, donor, and third-party targets in a follow-up study. Eight cases receiving HLA-identical marrow grafts never developed signs of GvH-D. Undetectable or very low frequencies (1/131,458) of minor HA-specific CTL-p were demonstrated pre-BMT. Two recipients, one of an HLA-A- and one of an HLA-DR-mismatched graft, exhibited low frequencies of recipient-specific CTL-p (1/66,920 and 1/85,577, respectively) before transplantation, which further decreased despite mild GvH-D grade I, or decreased within 3 months after grafting in the other case. Eight patients receiving HLA-identical grafts developed GvH-D. Recipient-specific CTL-p were less than 1/300,000 in five patients during limited GvH-D (four with grade I and one with grade II disease of the skin), but were detectable in three patients presenting with extensive GvH-D grades II to III and ranged from 1/7,993 to 1/210,108. The differences in post-BMT recipient-specific CTL-p frequencies between patients with GvH-D grades 0 to I (median, less than 1/300,000) and those with GvH-D grades II to III (median, 1/111,970) were statistically significant (P less than .05). Posttransplant lymphocytes from all 18 patients contained less than 1/300,000 CTL-p with specificity for donor targets. Comparison of third-party-reactive CTL-p frequencies between donor and post-BMT recipient lymphocytes showed a severe and long-lasting depletion subsequent to BMT, which was not related to infectious complications. Again, these differences reached the level of statistical significance (median CTL-p before BMT, 1/4,417; after BMT, 1/14,289; P less than .005).(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Studies on the mechanism of tolerance or graft-versus-host disease in allogeneic bone marrow recipients at the level of cytotoxic T-cell precursor frequencies. 154 51

Antithymocyte and antilymphocyte globulins (ALG) are currently used as immunosuppressive agents in organ transplantation and for the treatment of acute graft-versus-host disease and aplastic anemia. Since any type of immunosuppressive treatment is known to carry the risk of developing B-cell lymphoproliferative disorders, we investigated the in vitro effect of ALG on human B-cell activation and proliferation. The data demonstrate that whatever the source of lymphocytes used for ALG preparation (thymocytes, thoracic duct lymphocytes, B- or T-cell lines), (1) ALG react with both B- and T-cell lines, and (2) ALG contain antibodies specific for B cells (eg, CD21) or common to T and B cells (eg anti-beta 2-microglobulin, anti-HLA-DR, CD18, CD11a) in addition to T-cell-specific antibodies. Unlike all other T-cell mitogens tested (Concanavalin A [Con A], Pokeweek mitogen [PWM], CD3 and CD2 antibodies), ALG do not trigger B-cell differentiation into immunoglobulin-secreting cells at concentrations which induce maximum T-cell proliferation. This effect could be attributed to a direct interaction of ALG with B lymphocytes as shown by the capacity of ALG to block the response of purified B cells to a variety of activators. Furthermore, all the ALG tested were shown to inhibit the proliferation of six of the seven Epstein-Barr virus (EBV)-transformed lymphoblastoid cell lines and six of the seven Burkitt's lymphoma cell lines studied. This selective B-cell antiproliferative property of ALG was not reproduced with CD11a, CD18, CD21, CD24, or anti-HLA-DR monoclonal antibodies (MoAbs). These results suggest that, although suppressing T-cell responses, ALG treatment may directly control B cell proliferation to some extent, in keeping with the relatively low risk of posttransplant lymphoproliferative disorders reported with ALG.
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PMID:Antiproliferative effect of antilymphocyte globulins on B cells and B-cell lines. 156 43

An immunohistological study of epidermal keratinocytes for the intercellular adhesion molecule, ICAM-1 (CD54), was undertaken on skin biopsies from allogeneic bone marrow transplant recipients. In control biopsies from normal donors and patients prior to transplantation, staining was weak and confined to relatively few cells. After transplantation there was a significant increase in both the number of positive cells and their staining intensity in biopsies showing histological evidence of GVHD but not in those exhibiting normal appearances or epidermal abnormalities that could be attributed to cytotoxic drugs or irradiation. There was a strong positive correlation between ICAM-1 and HLA-DR expression by keratinocytes. All cases exhibiting increased ICAM-1 also exhibited an increase in HLA-DR antigens. The converse was not true, however, as 6 biopsies exhibited HLA-DR positivity without detectable increases in ICAM-1. Both ICAM-1 and HLA-DR antigen synthesis may be stimulated by local cytokine release following interactions between donor and recipient cells in the early posttransplant period. Our present findings suggest that immunostaining for ICAM-1 has little value in the early diagnosis of cutaneous GVHD but further, more detailed prospective studies would be of value.
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PMID:ICAM-1 expression on epidermal keratinocytes in cutaneous graft-versus-host disease. 167 3

We studied a severe combined immunodeficiency (SCID) patient who received transplantations with completely HLA-mismatched fetal liver and thymus from two different donors. The patient is now 14 years old, healthy and shows normal immunoresponses to recall antigens. His T cells are of donor origin, whereas the monocytes, B cells, and natural killer (NK) cells are of the recipient. The successful immunological reconstitution raised questions as to how T and B cells could collaborate across an HLA barrier and how tolerance was achieved. We have shown that tetanus toxin-specific T cell clones isolated from this patient recognized this antigen in the context of host and not of donor HLA-DR, indicating that those cells were educated in the host environment, presumably the thymus. Despite this, an unexpectedly high frequency of host-reactive clones was found that could recognize MHC antigens of the host. It was particularly striking that CD8+ CTL clones were obtained that recognized class I MHC antigens on the host cells. Nevertheless, the patient did not show any sign of acute or chronic graft-versus-host disease (GVHD). These data indicated that no or only incomplete clonal deletion had taken place in this patient and suggest the presence of a peripheral suppressor mechanism. Thus far, we have no indication for the existence of suppressor T cells. Inasmuch as it was found that host-reactive T cells fail to produce IL-4, which is exceptional for CD4+ T cells, we are exploring the possibility that abnormal cytokine production patterns of host-reactive T cells are associated with suppression of these cells in vivo.
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PMID:A SCID patient reconstituted with HLA-incompatible fetal stem cells as a model for studying transplantation tolerance. 168 May 8

Peripheral blood lymphocytes from 25 allogeneic bone marrow transplant recipients were studied serially using flow cytometry and two colour analysis. Fourteen patients were transplanted for haematologic malignancies, eight for aplastic anaemia, two for congenital immunodeficiencies and one for Morquio's disease. All patients were alive more than 100 days post-grafting; nine patients had chronic graft-versus-host disease (GVHD). Dual labelling with monoclonal antibodies, CD4/2H4, CD4/4B4, CD8/CD11, CD8/HLA-DR and CD8/Leu 7 was used to analyse the surface phenotypes of lymphocytes. The population of CD4+2H4+ cells was decreased, and CD8+CD11+, CD8+CD11- and CD8+Leu7+ cells were markedly increased in patients with chronic GVHD. The increase of CD8+CD11+, CD8+CD11- and CD8+Leu7+ cells closely correlated with clinical signs of chronic GVHD in each patient. These results suggest that CD8+ cells may play an important role in effector and/or suppressor mechanisms of chronic GVHD and could be used as an indicator of need for and response to treatment.
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PMID:Increased numbers of CD8+CD11+, CD8+CD11- and CD8+Leu7+ cells in patients with chronic graft-versus-host disease after allogeneic bone marrow transplantation. 169 37

Sweat gland abnormalities occur much more frequently than hitherto described in cutaneous graft versus host disease (GVHD). Two patterns of abnormalities were identified in 80 per cent of cases of acute GVHD: a cytopathic pattern consisting of a combination of basal vacuolopathy with or without lymphocytic infiltration and basal cell degeneration, and a proliferative pattern consisting of basal cell hyperplasia. In chronic GVHD, complete sweat gland destruction with fibrosis was commonly observed. Squamous metaplasia and dilation of the sweat glands were less frequently identified. Ki67 immunostaining confirmed proliferative activity in the basal cells of the distal duct. HLA-DR antigens were expressed on the basal cells of the duct and secretory glands in acute GVHD but not in normal skin. Langerhans cells were absent in both normal and abnormal sweat glands. The role of HLA-DR or Langerhans cells in the initiation of GVHD is questioned in the light of the new data and the primary involvement of proliferating cells is confirmed.
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PMID:The sweat gland in graft versus host disease. 169 40

The circulating lymphocytes of 88 consecutive patients following autologous, conventional, or T-cell depleted bone marrow transplantation were serially analyzed for B-cell surface antigen expression and function. In the majority of patients, except for those who developed chronic graft-versus-host disease, the number of circulating CD20+ B cell normalized by the fourth posttransplant month. The earliest detectable B cells normally expressed HLA-DR, CD19, surface immunoglobulin (slg), CD21, Leu-8, and lacked expression of CD10 (CALLA). In addition, the circulating B cells expressed CD1c, CD38, CD5, and CD23 for the first year following transplant, antigens that are normally expressed on a small percentage of circulating B cells in normal adults, but highly expressed on cord blood B cells. Similar to cord blood B cells, patient B cells isolated during the first year following transplant, proliferated normally to Staphylococcus aureus Cowan strain I (SAC), and produced IgM, but minimal or no IgG when stimulated with pokeweed mitogen and SAC, unlike normal adult B cells that produce both. The similar phenotype and function of posttransplant and cord blood B cells, and their similar rate of decline in patients and normal children adds further evidence to support the hypothesis that B-cell differentiation posttransplant is recapitulating normal B-cell ontogeny.
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PMID:B-cell differentiation following autologous, conventional, or T-cell depleted bone marrow transplantation: a recapitulation of normal B-cell ontogeny. 169 84

Graft-versus-host disease (GVHD) is an immunologically mediated disease occurring most frequently after allogeneic bone marrow transplantation. The aim of this study was to evaluate the contribution of immunohistochemistry in the diagnosis of cutaneous GVHD. Patients transplanted for either leukemia or beta-thalassemia were included in the study. Skin lesions of acute and chronic GVHD were examined both by direct immunofluorescence to detect immunoglobulin deposits and by an avidin-biotin-peroxidase complex technique to evaluate the inflammatory cell infiltrate. Epidermal and dermal fluorescent bodies (IgG and IgM) were frequently found in both acute and chronic GVHD. Most of the infiltrating cells were CD3+ T lymphocytes, with CD8+ cells representing the major cell population invading the epidermis both in acute GVHD and in chronic lichenoid GVHD. A small proportion of the dermal cells were CD14+ macrophages; no B cells were detected. HLA-DR, but not HLA-DQ antigens, were variably expressed by keratinocytes in all cases of acute GVHD and in chronic lichenoid GVHD. KL-1, a monoclonal antikeratin antibody specific for the 56.5 KD acidic polypeptide usually present in suprabasal keratinocytes, stained all epidermal layers, including the basal layer. Langerhans cells were dramatically reduced in number in the epidermis of both acute and chronic lichenoid GVHD. It is concluded that immunohistologic analysis may be supportive in the diagnosis of acute and early chronic lichenoid cutaneous GVHD.
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PMID:Immunohistochemistry of cutaneous graft-versus-host disease after allogeneic bone marrow transplantation. 193 60


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