Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0021051 (immunodeficiency)
 71,517 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

HLA typing was performed on 384 individuals of an isolated population of 1,500 people with a familial aggregate of lymphoma and immunodeficiency cases. Eighty-five % of the total population were descendants of the founding couple. First cousin marriages were common. There was a three-fold or higher increase of the following haplotypes as compared to the frequencies in Sheffield: HLA-A28,Bw35, HLA-A28, B18, HLA-A10, B18, HLA-A2, B18,HLA-A11, Bw40 and HLA-A11, B7. The frequency of HLA-A1, B8 was low (5.4%). The most common genotype was HLA-A2, B12/A2, B12 followed by HLA-A2, B12/A28, Bw35. We found 20 HLA homozygous individuals, of these 15 were HLA-A2, b12/a2, b12. There were two possible HLA cross-overs which may be confirmed and three postulated cross-overs which can never be confirmed as one or both parents of the individuals in question are deceased. Some of the haplotypes could be traced back to the first, second and third generations, i.e. to the first half of the nineteenth century. No single haplotype or antigen was shared by the patients.
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PMID:HLA haplotypes in a genetic isolate in Newfoundland. A population showing 8% homozygosity and a familial aggregate of lymphoma and immunodeficiency cases. 97 11

The authors report on five cases of Seckel syndrome type I primordial dwarfism, belonging to three unrelated sibships. Immunological and cytogenetic investigations with DEB test did not evidence immunodeficiency or chromosomal fragility. HLA phenotype studies revealed an identical haplotype in affected sibs: a possible linkage with HLA is therefore suggested. Cranial magnetic resonance was performed in three patients and did not evidence any anomaly. One affected female showed precocious puberty at 7 years of age.
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PMID:Seckel syndrome: report of three sibships with the type I primordial dwarfism. Possible linkage with HLA locus. 129 17

Asparagine-linked sugar chains of plasma membrane glycoproteins, which are formed by glycosylation during B cell maturation, were examined with B lymphoblastoid cell lines (LCLs) transformed by Epstein-Barr virus derived from healthy controls and patients with common variable immunodeficiency (CVI). Both two patients with CVI showed hypogammaglobulinemia and impaired B cell functions. LCLs from healthy controls and the patients showed CD19+ and HLA/DR+ in the cell surface and secreted IgM. In both healthy controls and the patients, the main oligosaccharide in asparagine-linked sugar chains of the membrane glycoproteins of LCLs was biantennary sugar chain with bisected GlcNAc (Gal2-GlcNAc2-Man3-GlcNAc-GlcNAc-Fuc-GlcNAcOT). Biantennary sugar chain with an alpha-fucosyl residue linked at the proximal GlcNAc was seen but biantennary sugar chain without an alpha-fucosyl residue at the proximal GlcNAc was little detected in each LCL. There was no difference in quality and quantity of asparagine-linked sugar chains between healthy controls and the patients. These results suggest that glycosylation during B cell maturation may not be impaired in patients with CVI.
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PMID:Asparagine-linked sugar chains of plasma membrane glycoproteins from healthy and common variable immunodeficiency B lymphoblastoid cell lines. 132 Mar 90

Seven immortalized B cell clones, five of which secreted specific human monoclonal antibodies (MAbs) against hepatitis B, tetanus toxoid, and Rhesus D antigens, were evaluated for their susceptibility to infection by human immunodeficiency virus types 1 and 2 (HIV-1 and HIV-2). Infection was confirmed in three human MAb-producing lines by detection of infectious virus and p24 antigen in culture supernates, by immunofluorescence, and by detection of viral DNA in cells by polymerase chain reaction. The infectable lines were as susceptible to HIV-1 infection as several T cell lines and remained persistently infected for several months, but in contrast to T cell controls, viral cytopathic effects were not observed. Levels of unintegrated viral DNA in the HB1 B cell line were significantly lower than in the HUT78 T cell line. Cell lines that were susceptible to HIV expressed HLA DR, CD20, and CD21, whereas the uninfectable cell lines did not express any of the markers tested. CD4 was undetectable or present on a small percentage of cells in two of the infectable cell lines. However, infection with HIV-1 was blocked more efficiently in B cells than in T cells by soluble CD4, anti-CD4 MAb, and dextran sulphate. The effect of HIV infection on human MAb secretion was variable, being reduced on a per-cell basis in one line, increased in another, and unchanged in a third.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Susceptibility of human monoclonal antibody-producing B cell lines to infection by human immunodeficiency virus. 133 86

We found that naive (CD45RA+) CD4 T cells have a lower capacity of adhesion to Epstein-Barr virus (EBV) immortalized B cells than memory (CD45RO+) CD4 T cells, as judged by conjugate formation. This would appear to be due to differences in the expression of adhesion molecules [lymphocyte function-associated antigen (LFA)-1, CD2]. However, kinetic studies showed that the degree of adhesion of naive T cells to B cells was stable over 60 min while that of memory T cells, like that of unseparated CD4 T cells, was characterized by a rapid formation and rapid dissociation of conjugates. This could be explained by a difference in the sensitivity of naive and memory CD4 T cells to down-regulation of antigen-independent adhesion by CD4-MHC class II interaction. Indeed, memory T cells also adhered stably to MHC class II(-) B cells. The adhesion of memory T cells, but not naive T cells, to MHC class II(+) B cells was sensitive to inhibition by OKT4a an anti-CD4 antibody, human immunodeficiency (HIV) gp160 (env) protein and a 12-mer peptide encompassing the 35-46 sequence of the HLA, DR beta 1 domain and previously shown to inhibit activation of HLA class II-restricted CD4 T cell responses. Since MHC class II expression did not influence the degree of conjugate formation by naive or memory CD4 T cells with B cells, CD4-MHC class II interaction does not appear to be involved in binding itself, but may down-regulate the adhesion of memory but not naive CD4 T cells.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Antigen-independent adhesion of CD45RA (naive) and CD45RO (memory) CD4 T cells to B cells. 135 61

Three patients infected with human immunodeficiency virus (HIV) presented with pseudotumoral splenomegaly, CD8 lymphocytosis (3.5-5.1 x 10(9)/l), and hypergammaglobulinaemia. Spleen and bone marrow showed diffuse CD8 lymphocyte and plasma-cell infiltration. Amplification of the T-cell-receptor gamma chain gene did not reveal any clonal T-cell population. Phenotypic analysis showed a predominance of CD8/CD57 suppressor T cells with expression of activation markers (DR and CD38). No cytotoxic T lymphocytes specific for HIV could be detected. The three patients shared the HLA haplotype A1, B8, DR3. The association with this haplotype suggests a genetically determined host immune response to HIV.
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PMID:CD8 lymphocytosis and pseudotumoral splenomegaly in HIV infection. 136 50

Some types of reused dental equipment, especially handpieces and their attachments for drilling and cleaning teeth, might be responsible for cross-contamination if patient material were to lodge temporarily in difficult-to-disinfect internal mechanisms. This possibility is worrisome with respect to transmission of hepatitis B and human immunodeficiency viruses (HBV, HIV). Previous cross-contamination studies have relied on laboratory experiments with bacteria or dye tracers. To assess possible risk more thoroughly, we tested 30 new prophylaxis angles and 12 new high-speed handpieces to see whether they would take up and expel contaminants in laboratory and clinical trials. In treatments of three patients, including two infected with HIV, human-specific DNA (beta-globin, HLA DQ alpha) and HIV proviral DNA were detected inside or coming back from the devices. Similarly, when handpieces were operated in contact with blood pooled from HBV-infected patients, HBV DNA was detected in samples taken from inside the equipment and from their attached air/water hoses. When we used bacteriophage phi X174 as a model virus in laboratory tests, many infective viral particles were recovered from internal mechanisms of handpieces, their connecting air/water hoses, and from water spray expelled when the equipment was reused. We recommend that reused high-speed, air-driven handpieces and prophylaxis angles should be cleaned and heat-treated between patients. Further studies are needed to determine ways of eliminating the risks associated with exhaust hoses and air/water input lines.
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PMID:Cross-contamination potential with dental equipment. 809 83

Although the immunologic basis of protective immunity in human immunodeficiency virus type 1 (HIV-1) infection has not yet been defined, virus-specific cytotoxic T lymphocytes (CTL) are likely to be an important host defense and may be a critical feature of an effective vaccine. These observations, along with the inclusion of the HIV-1 envelope in the majority of vaccine candidates presently in clinical trials, underscore the importance of the precise characterization of the cellular immune responses to this protein. Although humoral immune responses to the envelope protein have been extensively characterized, relatively little information is available regarding the envelope epitopes recognized by virus-specific CTL and the effects of sequence variation within these epitopes. Here we report the identification of two overlapping CTL epitopes in a highly conserved region of the HIV-1 transmembrane envelope protein, gp41, using CTL clones derived from two seropositive subjects. An eight-amino acid peptide was defined as the minimum epitope recognized by HLA-B8-restricted CTL derived from one subject, and in a second subject, an overlapping nine-amino acid peptide was identified as the minimal epitope for HLA-B14-restricted CTL clones. Selected single amino acid substitutions representing those found in naturally occurring HIV-1 isolates resulted in partial to complete loss of recognition of these epitopes. These data indicate the presence of a highly conserved region in the HIV-1 envelope glycoprotein that is immunogenic for CTL responses. In addition, they suggest that natural sequence variation may lead to escape from immune detection by HIV-1-specific CTL. Since the region containing these epitopes has been previously shown to contain an immunodominant B cell epitope and also overlaps with a major histocompatibility complex class II T cell epitope recognized by CD4+ CTL from HIV-1 rgp160 vaccine recipients, it may be particularly important for HIV-1 vaccine development. Finally, the identification of minimal CTL epitopes presented by class I HLA molecules should facilitate the definition of allele-specific motifs.
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PMID:Identification of overlapping HLA class I-restricted cytotoxic T cell epitopes in a conserved region of the human immunodeficiency virus type 1 envelope glycoprotein: definition of minimum epitopes and analysis of the effects of sequence variation. 137 50

Cytotoxic T lymphocytes (CTL) are present at high activities in adult patients infected with the human immunodeficiency virus (HIV). In this report, CTL effectors were identified in peripheral blood mononuclear cells (PBMC) of children born to HIV-1-infected mothers. These CTL killed HLA-matched HIV-1-infected H9 target cells or doubly transfected P815-A2-env, gag or nef mouse tumor cells, which expressed the viral antigens in association with HLA-A1/A3 or HLA-A2, respectively. HIV-1-specific CTL were detected early after birth (less than 2 months) and remained present during the asymptomatic phase of the infection. As in HIV-1-infected adults, HIV-specific CTL declined with disease progression. Surprisingly, HIV-1-specific CTL were detected in the PBMC of three children who subsequently became seronegative.
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PMID:Cytotoxic T lymphocyte responses in the peripheral blood of children born to human immunodeficiency virus-1-infected mothers. 138 9

CD4+ T cell recognition of the simian immunodeficiency virus (SIV) surface envelope (env) glycoprotein was examined by using a panel of 10 T cell lines and 4 T cell clones derived from 10 individual macaques immunized with inactivated SIV or recombinant SIV env proteins. The results demonstrated that CD4+ T cells from each animal recognized between 1 and 7 peptides in 4 distinct regions of the protein including both variable and conserved domains. MLR of PBMC from selected macaques together with RFLP analysis by using the HLA DR beta probes suggested that animals of distinct MHC class II haplotypes can recognize identical peptides. These T cell epitopes within conserved regions of the envelope protein, together with identified linear B cell epitopes recognized by neutralizing antibodies, may be relevant in vaccine design.
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PMID:Heterogeneity in the recognition of the simian immunodeficiency virus envelope glycoprotein by CD4+ T cell clones from immunized macaques. 138 39


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