Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0001175 (AIDS)
 120,706 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Disseminated cytomegalovirus (CMV) infection is a frequent occurrence in human immunodeficiency virus-infected humans and in simian immunodeficiency virus (SIV)-infected rhesus macaques. Rhesus macaques are a suitable animal model with which to study in vivo interactions between CMV and AIDS-associated retroviruses. Since cytotoxic T lymphocytes (CTL) play a major role in control of viral infections, we have characterized CMV-specific CTL responses in SIV-infected and uninfected rhesus macaques. Autologous fibroblasts infected with rhesus CMV were used to stimulate freshly isolated peripheral blood mononuclear cells from CMV-seropositive animals. Following in vitro stimulation, specific CTL activity against CMV-infected autologous fibroblasts was detected in CMV-seropositive but not in CMV-seronegative normal macaques. CMV-specific CTL activity comparable to that in normal animals was also detected in two CMV-seropositive macaques infected with a live attenuated SIV strain (SIVdelta3) and in two of three macaques infected with pathogenic SIV strains. The CMV-specific CTL response was class I major histocompatibility complex restricted and mediated by CD8+ cells. An early CMV protein(s) was the dominant target recognized by bulk CTL, although the pattern of CTL recognition of CMV proteins varied among animals. Analysis of CMV-specific CTL responses in macaques should serve as a valuable model for CMV immunopathogenesis and will facilitate prospective in vivo studies of immune interactions between CMV and SIV in AIDS.
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PMID:Cytotoxic T-lymphocyte responses to cytomegalovirus in normal and simian immunodeficiency virus-infected rhesus macaques. 889 93

The search for a suitable and reliable animal model for human AIDS that is easy to use on a large scale continues. Here we describe a new condition in mice that closely resembles human AIDS, namely, chronic lymphoproliferation with dramatic depletion of CD4-positive cells, progressive impairment of the immune responses, and Kaposi's sarcoma-like tumors or terminal B-lymphomas. The AIDS-like disease was primarily induced by mating BALB/c female mice to C57BL/6 males during a 1-year period (7-10 allogeneic pregnancies) followed by immunization with paternal lymphocytes. The disease is sexually and vertically transmissible, transferrable by cell-free plasma and is associated with autoimmune reactions to major histocompatibility complex antigens and CD4 cells. We hope that this becomes a model for studying the mechanisms of AIDS immunopathogenesis and immune-based treatment approaches.
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PMID:A new transmissible AIDS-like disease in mice induced by alloimmune stimuli. 898 38

The major histocompatibility complex (MHC) contains at least a hundred genes over 4 megabases of DNA. Within the MHC there are several new multigene families which have been recently described. PERB11 is a multigene family which occurs over the class I and central region of the MHC. Two members of the family have been shown to be functional and share domains with members of the supergene family including HLA class I, FcRn, and Zn-alpha2-glycoprotein molecules. The two functional members are contained within an area of the MHC which has been associated with increased susceptibility to autoimmune diseases such as insulin-dependent diabetes mellitus and also rapid progression to AIDS following HIV-1 infection. Intralocus and interlocus differences between PERB11.1 and PERB11.2 include: (1) several nucleotide substitutions leading to amino acid changes; (2) presence and absence of potential glycosylation sites; (3) insertions and deletions leading to a frame shift resulting in diversity at the amino acid level and an early termination signal. There are ten different alleles of PERB11.1 including one allele which contains a frame shift in the transmembrane region causing a putative truncated molecule lacking the cytoplasmic tail. The significance of this polymorphism in disease associations is under investigation. The most divergent domain is the transmembrane region when PERB11.1 and PERB11.2 are compared. The results suggest that these two molecules may have different functions.
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PMID:Allelic and interlocus comparison of the PERB11 multigene family in the MHC. 899 88

IMGT, the international ImMunoGeneTics database, is an integrated database specializing in immunoglobulins, T-cell receptors (TcR) and major histocompatibility complex (MHC) of all vertebrate species, initiated and co-ordinated by Marie-Paule Lefranc, CNRS, Montpellier II University, Montpellier, France (lefranc@ligm.crbm.cnrs-mop.fr). IMGT includes two databases: LIGM-DB (for immunoglobulins and TcR) and MHC/HLA-DB. IMGT comprises expertly annotated sequences and alignment tables. LIGM-DB contains more than 19 000 immunoglobulin and TcR sequences from 78 species. MHC/HLA-DB contains class I and class II human leukocyte antigen alignment tables. An IMGT tool, DNAPLOT, developed for immunoglobulins, TcR and MHC sequence alignments, is also available. IMGT works in close collaboration with the EMBL database. IMGT goals are to establish a common data access to all immunogenetics data, including sequences, oligonucleotide primers, gene maps and other genetic data of immunoglobulins, TcR and MHC molecules, and to provide a graphical user-friendly data access. IMGT will have important implications in medical research (repertoire in autoimmune diseases, AIDS, leukemias, lymphomas), therapeutical approaches (antibody engineering), genome diversity and genome evolution studies. IMGT can be accessed at http://imgt.cnusc.fr:8104 and http://www.ebi.ac.uk/IMGT
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PMID:IMGT, the international ImMunoGeneTics database. 901 37

Macaques have been protected against infection with human cell-grown SIVmac by immunization with antigens encoded by the human major histocompatibility complex (MHC). Here, we investigated the efficacy of alloimmunization with simian B cells expressing high levels of MHC class I and class II molecules to confer protection against systemic challenge with simian-grown SIVmac. Eight rhesus macaques were vaccinated with glutaraldehyde-fixed and beta-propiolactone-inactivated herpesvirus papio-transformed B cells. Four of the macaques received 5 doses, the others 10. Animals were challenged with rhesus macaque spleen-derived cell-free SIVmac. Allogeneic B cells elicited antibody responses to rhesus MHC class I and II but failed to protect animals against infection. Anti-MHC class I antibodies were restricted in specificity and failed to recognize MHC class I from some B lymphoblastoid cell lines (B-LCLs) including a B-LCL from the animal in whose cells the challenge virus was grown. Vaccinated animals responded to self-MHC class I antigens but not to self-MHC class II antigens from peripheral blood mononuclear cells (PBMCs). Animals that underwent the shorter immunization regimen had transiently enhanced PBMC-associated virus loads after challenge, whereas the average virus-infected cell load was reduced in animals that underwent the more extensive immunization. These results suggest that antibody responses to allogeneic MHC molecules do not protect against infection with immunodeficiency lentiviruses.
AIDS Res Hum Retroviruses 1997 Jul 20
PMID:Anti-major histocompatibility complex antibody responses to simian B cells do not protect macaques against SIVmac infection. 959 7

Approximately 10% of HIV-infected patients, the rapid progressors, progress to AIDS within the first 2 to 3 years of HIV infection. Their biological characteristics are not clearly known. They have a particular phenotype (DR) of major histocompatibility complex class-II. Anti-HIV antibodies are not neutralizing and may even be facilitators in vitro. Progressors CTL responses are also defective and the production of the cytokines, specially the chemokines RANTES, MIP-1 alpha et MIP-1 beta which may have a role in inhibition of cellular infection by HIV, is impaired. In addition, the rapid progressors have high levels of inflammatory markers which suppose a chronic activation of the immune system. The virological findings are more inconsistent. A uniform finding is a high viral load that does not fall dramatically after primary HIV infection. Some rapid progressors may be infected with more rapidly replicating, virulent HIV strains. However, the question regarding the homogeneity or the other characteristics of viral load remains to be resolved.
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PMID:[Characteristics of rapid progressors in HIV infection]. 923 42

The purpose of the study was to examine how immune parameters related to non-major histocompatibility complex (MHC) restricted cytotoxicity changed with respect to progression and duration of human immunodeficiency virus (HIV) infection. Forty-one HIV seropositive subjects with a known time for seroconversion were included. The major finding was that a low percentage and number of natural killer (NK) cells were found in the group who had a rapid progression to acquired immune deficiency syndrome (AIDS) (less than 70 months following seroconversion) compared with those progressing more slowly to AIDS (more than 70 months following seroconversion). Furthermore, a significant correlation was found between the number of months from seroconversion to the diagnosis of AIDS and percentages of CD16+ cells (rs = 0.811, P < 0.01), CD56+ cells (rs = 0.647, P < 0.05), and CD16+CD56+ cells (rs = 0.839, P < 0.01) as well as the concentration of CD16+CD56+ cells in the blood (rs = 0.699, P < 0.05) No differences were found in percentages and concentrations of NK cell subsets between subjects with a long history (more than 6 years) versus a short history (less than 6 years) of HIV infection without AIDS. Furthermore, no negative correlations were found between the concentration of any NK subsets and the number of months since seroconversion in HIV seropositive individuals without AIDS. The total concentration of CD16+, CD56+, and CD16+CD56+ cells was lower in the group of HIV seropositive subjects compared with HIV seronegative subjects (age and sex matched), and the concentration of CD16+ cells was lower in those with AIDS than in those without AIDS. In conclusion, low concentration of NK cells in the blood was associated with a more rapid disease progression, indicating that defective non-MHC restricted cytotoxicity may be associated with HIV disease progression.
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PMID:Clinical progression of HIV infection: role of NK cells. 924 13

The role of the major histocompatibility complex (MHC) in the pathogenesis of AIDS is complex because of compounding variables within the virus, host, and environment. Important variables can be controlled by using the experimental animal model of AIDS induced by simian immunodeficiency virus in rhesus monkeys (Macaca mulatta). We studied whether the MHC type influenced which opportunistic infections arose in an individual monkey. Several associations were found. For example, cytomegalovirus was strongly associated with Mamu-B6 (p < 0.001), whereas Cryptosporidium was associated strongly with Mamu-DR3 (p < 0.001). We also found that having one opportunistic infection increased the risk of having another.
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PMID:Correlation of major histocompatibility complex with opportunistic infections in simian immunodeficiency virus-infected rhesus monkeys. 935 65

There is a consensus of opinion that central nervous system (CNS) involvement takes place in a large proportion of patients with the acquired immune deficiency syndrome (AIDS). However, uncertainty still remains about how often and how early the CNS is infected during the early asymptomatic stage as some researchers still believe that low copy of human immunodeficiency virus type 1 (HIV-1) identified in the brains using polymerase chain reaction (PCR) represents HIV harboured in the infected cells trapped in cerebral blood vessels. In this review, the neurological abnormalities in HIV-1 positive pre-AIDS individuals are discussed from three points of view: neuropsychiatric and neurophysiological, involvement of cerebrospinal fluid (CSF) and brain pathology. In particular, our investigations of the brains of asymptomatic individuals have demonstrated that HIV-1 DNA was present in about half (17/36) of brains studied (copy numbers of HIV-1 DNA were detected and the possibility of contamination from the blood was calculated and excluded). Astro- (34/36) and micro- (31/36) gliosis and meningitis (11/36) were found. Immune activation, revealed by elevated expression of major histocompatibility complex (MHC) class II antigens, was previously demonstrated in the brains of patients with AIDS and was also present before the development of AIDS. Furthermore, demonstration of highly expressed cytokines (tumor necrosis factor (TNF)-alpha, interleukin (IL)-1, 4, 6) possibly explains the neuropathological changes and neuronal damage (confirmed by the demonstration of apoptotic neurons by in situ end labelling) seen in these brains. We conclude that HIV-1 is present in the brains of HIV-1 infected individuals at early stages of the infection and that HIV-1 induces brain damage in a direct as well as indirect way. This is a worrying conclusion which makes it mandatory to reconsider the time at which treatment must be applied in HIV-1 infection.
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PMID:Early HIV-1 infection of the central nervous system. 938 15

Assays performed in the diagnostic immunology laboratory support the diagnosis and management of a wide spectrum of clinical conditions. This chapter reviews immunologic principles as they apply to diagnostic laboratory assays. Most of the determinations are based on well-established principles of antigen-antibody reactions. Some of the specific areas discussed include flow cytometric analyses, critical in the care of patients with hematologic malignancies, with the acquired immunodeficiency syndrome, or undergoing transplantation, and protein electrophoretic assays to identify the presence of monoclonal gammopathies. We also discuss the use of molecular techniques in the diagnosis of hematologic malignancies and primary immunodeficiencies, characterization of the major histocompatibility complex, and enumeration of viral burden.
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PMID:Introduction to diagnostic laboratory immunology. 939 43


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