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)

To assess the hypothesis that the human immunodeficiency virus (HIV) might mimic major histocompatibility complex (MHC) allodeterminants and interact with T-cell receptors (TCRs) of alloreactive T-cells, we have done a preliminary analysis of the range of alpha beta TCR gene products in 16 HIV-1-seropositive individuals with normal CD4 counts and in 16 healthy HIV-1-negative controls. Using a panel of monoclonal antibodies with a two-colour direct immunofluorescence method, we found a significant increase in the expression of the V beta 5.3 subfamily in the HIV-positive patient group compared with controls (p less than 0.01). Selected increase in expression of V beta sequences has been described in various autoimmune conditions and our findings raise the possibility that the immunopathological damage from HIV infection may be due to the induction of autoreactivity. If HIV does mimic MHC II, the normal immune response to the virus could represent an autoimmune process similar to graft-versus-host disease.
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PMID:T-cell receptor variable gene products and early HIV-1 infection. 135 71

As HIV readily kills CD4 cells in vitro it has been widely assumed that this would account for the declining CD4 counts in vivo. A growing number of reports suggest that the pathogenesis of AIDS is considerably more complex than had been thought. A number of indirect mechanisms for CD4 cell death have been proposed. In this review of alternative theories which could explain the features of AIDS, autoreactivity and genetic restriction to the development of disease are considered the most important. In addition it is suggested that if HIV is able to mimic MHC antigens on the surface of antigen presenting cells then this could stimulate 'allo reactive' T lymphocytes, which would explain the marked similarity of HIV infection to chronic graft versus host disease.
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PMID:The pathogenesis of AIDS: classical and alternative views. 158 22

Evidence is accumulating that susceptibility to disease following HIV infection is genetically restricted. In addition, activation of the immune response appears to play an important role in disease progression. Here, John Habeshaw and colleagues propose that HIV envelope glycoproteins mimic foreign MHC molecules and, in doing so, stimulate alloreactive lymphocytes. This activation may explain the marked clinical and immunological similarities between chronic GVHD and AIDS.
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PMID:Does the HIV envelope induce a chronic graft-versus-host-like disease? 162 48

The immune deficiency induced by HIV has its origin in the interaction of the outer envelope glycoprotein gp120/gp41 with receptors present on human immunocytes. Virus binding to cells, virus entry and subsequent compartmentalization resulting in productive infection depends on the interaction of gp120/gp41 with CD4 and other accessory molecules. Gp120 and HIV are markedly immunosuppressive of T-cell responses and, in addition, HIV can functionally delete antigen responsiveness of T cells. Abolition of CD4 binding, by denaturation of gp120, allows study of T-cell epitopes in gp120 and shows the denatured molecule is highly immunogenic even in naive subjects (F. Manca, unpublished). The gp120-binding site of CD4 is shared with MHC class II molecules and the reaction of antibodies within this region of CD4 induces conformational changes that may be significant for virus entry into cells or for syncytial formation. The HIV envelope contains sites of sequence homology with monomorphic human MHC class II sites that do not appear to be naturally immunogenic in humans. In addition to the properties of gp120, it is hypothesized that HIV envelope may also represent an 'alloepitope' of class II to the human T-cell repertoire, and is therefore able to induce a chronic allogeneic response not dissimilar to experimentally induced GVHD. These features are of potential importance both for primary vaccination against HIV, and for the long-term treatment of HIV seropositive patients. Induction of effective T-cell responses to gp120 require use of a denatured or otherwise modified product lacking CD4-binding capacity. The potential distortion of the TCR repertoire by the class-II-homologous and CD4-interactive sequences must be assessed.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:AIDS pathogenesis: HIV envelope and its interaction with cell proteins. 187 30

Many questions are raised in this review about the role of adult donor granulocyte transfusions in the setting of overwhelming bacterial neonatal sepsis. There clearly exists a number of variables, which influence the survival and morbidity associated with bacterial sepsis. The important differences in these studies highlight the need for prospective large multicenter studies to definitely clarify these issues. Important criteria, which are yet to be established and which impact significantly, include the time of administration of adjuvant granulocytes, the number of granulocytes that need to be harvested, which group of neonates require early granulocyte transfusions, the best method for optimal and easy granulocyte collection, the frequency and intervals of granulocyte transfusions, and improved methods for the early identification of neonatal candidates who would benefit from the granulocyte transfusions. The benefits of granulocyte transfusions (ie, the improvement in morbidity and mortality) in septic neutropenic neonates must be weighed against the possible and reported side effects associated with such transfusions. Adverse reactions including graft-versus-host disease, CMV, HIV and hepatitis infection, fluid retention and pulmonary edema, blood group sensitization, and pulmonary insufficiency may all result from the use of granulocyte transfusions in a host who has evidence of developmental immaturity. All future studies must continue to evaluate these potential complications to balance and analyze the true benefits of survival with reported treatment results. Recently, a number of investigators including ourselves, have begun to examine the role of alternate adjuvant immunotherapy in enhancing neonatal host defense in the clinical setting of overwhelming bacterial sepsis.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:The use of granulocyte transfusion in neonatal sepsis. 213 12

The survey of the characteristics of HIV infection implicates the binding of HIV env to the CD4 receptor as the principal cause of the resulting immunodeficiency. There is evidence that such binding selectively impairs self-recognition. The resulting immunodeficiency syndrome has the characteristics of graft vs. host disease, consistent with chronic allogeneic and semiallogeneic GVHD in mouse-models. since these syndromes are believed to result from triggering the established immunoregulatory mechanisms necessary to maintain self-tolerance, vaccination to prevent AIDS should aim to correct the inability of the HIV host mount an immune response against CD4 binding epitopes on HIV gp120, preferably without exposing the vaccine to intact envelope glycoprotein. Since the AIDS syndrome is probably a defect in net-work immunoregulation, the most appropriate target for therapy and for vaccination is the idiotype of anti-CD4 antibodies that block CD4/env interaction.
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PMID:The relevance of HIV env/CD4 interactions to the pathogenesis of acquired immune deficiency syndrome. 267 11

From March 1982 to December 1986, 32 patients with standard risk leukaemia were conditioned for allogeneic bone marrow transplantation (BMT) with low dose fractionated total body irradiation (TBI) after infusion of alkylating agents. This series includes six children and 26 adults. Minimal follow-up was 24 months. The total dose of 11 Gy, given in 5 daily fractions of 2.20 Gy, was given in the lateral position, following chemotherapy with either melphalan or cyclophosphamide. Lungs were shielded for 2 out of the 5 fractions. All patients had in vivo dosimetry. The death rate is 25% without relapse or rejection. Disease-free survival is 73% at 5 years. Toxic deaths are detailed: 2 from sepsis and veino-occlusive disease of the liver, 3 from severe graft versus host disease (GVHD), 2 from GVHD associated with virus pneumonitis and one from HIV infection. Fractionated low dose rate TBI is discussed regarding its decreased toxicity and its efficiency for disease control.
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PMID:Fractionated total body irradiation and allogeneic bone marrow transplantation for standard risk leukemia. 269 33

Jejunal biopsy specimens from 20 human immunodeficiency virus (HIV) positive male homosexual patients were analysed and compared with those of a control group to determine whether the abnormalities were caused by the virus or by opportunistic infection. The degree of villous atrophy was estimated with a Weibel eyepiece graticule, and this correlated strongly with the degree of crypt hyperplasia, which was assessed by deriving the mean number of enterocytes in the crypts. The density of villous intraepithelial lymphocytes fell largely within the normal range, either when expressed in relation to the number of villous enterocytes or in relation to the length of muscularis mucosae. Villous enterocytes showed mild non-specific abnormalities. Pathogens were sought in biopsy sections and in faeces. Crypt hyperplastic villous atrophy occurred at all clinical stages of HIV disease and in the absence of detectable enteropathogens. An analogy was drawn between HIV enteropathy and the small bowel changes seen in experimental graft-versus-host disease. It is suggested that the pathogenesis of villous atrophy is similar in the two states, the damage to the jejunal mucosa in HIV enteropathy being inflicted by an immune reaction mounted in the lamina propria against cells infected with HIV.
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PMID:Jejunal enteropathy associated with human immunodeficiency virus infection: quantitative histology. 270 44

A 30-yr-old man with chronic granulocytic leukaemia received a bone marrow transplant from his histocompatible sister in December 1982. His post-transplant course was complicated by Grade III graft-versus-host disease and multiple infectious episodes until his death from pneumonia on d + 190. He was later found to be seropositive for anti-HIV at the time of his death. Retrospective analysis of stored sera showed a transient period of seropositivity from d + 11 to d + 20 thought to reflect passive transfer of antibody from a blood product transfused prior to d + 11 when he was also exposed to infectious virus. He remained seronegative until d + 78 when anti-HIV was again found. Seropositivity persisted until his death and was attributed to endogenous antibody response. Although it is unclear whether his clinical course was due to AIDS, exposure of an immunosuppressed patient to HIV may be associated with more rapid development of clinical disease.
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PMID:HIV infection due to a platelet transfusion after allogeneic bone marrow transplantation. 331 96

Since bone-marrow transplant recipients receive considerable quantities of packed-cell, platelet and sometimes leukocyte transfusions, as well as the donor marrow infusion, it would be predictable that acquired immunodeficiency syndrome (AIDS) by blood-product transfusion would occur in this patient population. We report here two patients who received HLA-identical sibling bone-marrow transplants for acute non-lymphoblastic leukaemia during their first remission. Both developed category-A AIDS at days 342 and 546 after transplantation, respectively. Neither patient belonged to any known high-risk group for AIDS, other than having received a blood-product transfusion. One of the two patients is now known to have received blood from a donor who was human immunodeficiency virus (HIV) seropositive. Both patients developed Pneumocystis carinii pneumonia and other opportunistic infections, and both have died of AIDS without evidence of recurrence of their leukaemia. One patient had no chronic graft-versus-host disease (GVHD) and the other had mild chronic GVHD of the mouth. Since severe opportunistic infections are rare after transplantation in the absence of GVHD, their late occurrence after transplantation should raise the suspicion of AIDS. This complication is likely to have an adverse impact on the long-term survival of patients who received bone-marrow transplants between 1981 and the introduction of effective screening tests for HIV infection in blood donors.
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PMID:The development of the acquired immunodeficiency syndrome after bone-marrow transplantation. 331 52


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