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)

Using gag protein of feline immunodeficiency virus (FIV) expressed in Escherichia coli, an enzyme-linked immunosorbent assay (ELISA) system was developed for detection of antibodies to FIV gag protein in cat sera. With serum samples from cats experimentally infected with several strains and an infectious molecular clone of FIV, increases of the antibody titers to FIV gag protein were observed in all cases by the ELISA at early stage of infection. When we examined a total of 415 field cat sera which were previously tested by an indirect immunofluorescence assay (IFA), 9 (12.9%) out of 70 IFA positive sera were judged as negative by the ELISA. However, all 3 serum samples tested among the 9 IFA positive sera had antibodies to gp130 but not to p26 by a radioimmunoprecipitation assay. The results indicated that some IFA positive sera did not have antibodies to the p26 though they have antibodies to other proteins specific for FIV.
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PMID:Detection of anti-gag antibodies of feline immunodeficiency virus in cat sera by enzyme-linked immunosorbent assay. 131 10

Two murine monoclonal antibodies (MAbs), designated MATG2014 and MATG2033, were generated. They are reactive with the external envelope glycoprotein gp130 of the simian immunodeficiency virus of macaque monkey (SIVmac251), and display a cell-free virus neutralizing activity in vitro. In addition, MATG2014 cross-reacts with HIV-2Rod gp140. Epitope mapping of these MAbs was performed by screening and SIVmac peptide library expressed in yeast and confirmed using synthetic peptides. MATG2014 and MATG2033 recognize two overlapping epitopes localized in an 18 residue domain between amino acid 171 and 188 of the SIVmac251 gp130. Sera from experimentally SIV-infected macaques are immunoreactive with this neutralizing domain. Sequence comparison with related SIV and HIV-2 viral strains indicates a low variability of this region, consistent with the cross-reactivity of MATG2014 with HIV-2Rod gp140. This domain should then be considered in designing experimental vaccines.
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PMID:Identification of a neutralizing domain in the external envelope glycoprotein of simian immunodeficiency virus. 138 Feb 63

Five pregnant (two to three and one-half months) Macaca fascicularis seroconverted following immunization with sucrose-gradient purified and formalin-inactivated whole simian immunodeficiency virus (SIVmac251). No untoward effects on fetal maturation were observed during the immunization of the mothers. Antibodies to SIVmac251 (also those with in vitro neutralizing activity) were passively transferred to the offspring but disappeared within two to six months after birth. Antibodies to env glycoprotein (gp130) lasted longer than those against viral gag proteins (p26,p60).
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PMID:Vaccination of pregnant cynomolgus monkeys with whole formalin-inactivated SIVmac251. 143 72

Retroviral envelope glycoproteins interact with cell receptors and are targets for antiviral immune responses in infected hosts. Macaque simian immunodeficiency virus (SIVmac) is a T-lymphocytopathic lentivirus which causes an AIDS-like disease in rhesus macaques. The envelope gene of SIVmac encodes a precursor glycoprotein (gp160) which is cleaved into an external domain (gp130) and a transmembrane domain (gp32). To investigate the functional and immunological properties of the SIV external envelope glycoprotein, we have used genetically engineered mammalian cells to produce recombinant gp130 (rgp130). The rgp130 has the appropriate molecular weight, is glycosylated, and has native conformation as determined by binding to the cell receptor for SIV, the CD4 antigen. Rhesus macaques immunized with purified rgp130 formulated in muramyl dipeptide adjuvant generated high titers of antienvelope antibodies. Antibodies from these macaques were tested for in vitro virus neutralization; very low or undetectable levels of neutralization were observed. In contrast, neutralizing antibodies were readily detected in sera from goats immunized with rgp130. With respect to cell-mediated immunity, proliferative responses to rgp130 were demonstrated in peripheral blood monocyte cells (PBMC) from macaques immunized with the recombinant glycoprotein as well as in PBMC from SIV-infected animals. These results show that rgp130 is functional and immunogenic; the potential of rgp130 for protective immunization remains to be determined.
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PMID:Functional and immunological characterization of SIV envelope glycoprotein produced in genetically engineered mammalian cells. 176 Feb 29

The processing and transport of the envelope glycoprotein complex of feline immunodeficiency virus (FIV) in the persistently infected Crandell feline kidney (CRFK) cell line were investigated. Pulse-chase analyses revealed that the glycoprotein is synthesized as a precursor with an Mr of 145,000 (gp145) and is quickly trimmed to a molecule with an Mr of 130,000 (gp130). Treatment of gp130 with endoglycosidase H (endo H) resulted in a protein with an Mr of 75,000, indicating that nearly half the weight of the gp130 precursor consists of endo H-sensitive glycans during biosynthesis. Chase periods of up to 8 h revealed intermediates during the further processing of this glycoprotein precursor. Initially, two minor protein species with apparent Mrs of 100,000 and 90,000 were detected along with gp130. At later chase times these two species appeared to migrate as a single dominant species with an Mr of 95,000 (gp95). Concomitant with the appearance of gp95 was another protein with an Mr of approximately 40,000 (gp40). Chase periods of up to 8 h revealed that approximately half of the precursor was processed into the gp95-gp40 complex within 4 h. gp95 was efficiently transported from the cell into the culture medium by 1 to 2 h after labeling, whereas gp40 was not observed to be released from infected CRFK cells. Analysis of the processing in the presence of monensin, castanospermine, and swainsonine also suggests the existence of these intermediates in the processing of this lentivirus glycoprotein. As with human immunodeficiency virus, virus produced in the presence of glucosidase inhibitors and reduced infectivity for T-lymphocyte cultures.
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PMID:Processing of the glycoprotein of feline immunodeficiency virus: effect of inhibitors of glycosylation. 184 41

Simian immunodeficiency virus (SIV), a lymphocytopathic lentivirus, induces an AIDS-like disease in rhesus macaques (Macaca mulatta). A pathogenic molecular clone of rhesus macaque SIV (SIVmac), SIVmac-239, replicates and induces cytopathology in T lymphocytes but is restricted for replication in macrophages. In contrast, a nonpathogenic molecular clone of SIVmac, SIVmac-1A11, replicates and induces syncytia (multinucleated giant cells) in cultures of both T lymphocytes and macrophages. SIVmac-1A11 does not cause disease in macaques. To map the viral determinants of macrophage tropism, reciprocal recombinant genomes were constructed between molecular clones of SIVmac-239 and SIVmac-1A11. Infectious recombinant viruses were rescued by transfection of cloned viral genomes into permissive lymphoid cells. Analysis of one pair of reciprocal recombinants revealed that an internal 6.2-kb DNA fragment of SIVmac-1A11 was necessary and sufficient for both syncytium formation and efficient replication in macrophages. This region includes the coding sequences for a portion of the gag gene, all of the pol, vif, vpr, and vpx genes, the first coding exons of tat and rev, and the external env glycoprotein gp130. Thus, the transmembrane glycoprotein of env, the nef gene, the second coding exons of tat and rev, and the long terminal repeats are not essential for in vitro macrophage tropism. Analysis of additional recombinants revealed that syncytium formation, but not virus production, was controlled by a 1.4-kb viral DNA fragment in SIVmac-1A11 encoding only the external env glycoprotein gp130. Thus, gp130 env of SIVmac-1A11 is necessary for entry of virus into macrophages but is not sufficient for a complete viral replication cycle in this cell type. We therefore conclude that gp130 env and one or more genetic elements (exclusive of the long terminal repeats, transmembrane glycoprotein of env, and second coding exons of tat and rev, and nef) are essential for a complete replication cycle of SIVmac in rhesus macaque macrophages.
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PMID:Identification of viral determinants of macrophage tropism for simian immunodeficiency virus SIVmac. 192 Jun 17

We examined the structural variability of the external glycoprotein (gp130) of a cloned simian immunodeficiency virus (SIV) in culture. Cloned SIVmac142 was either permanently propagated in HUT-78 cells or sequentially passaged in MT-2 cells. After 12, 24 and 60 passages of permanent or lytic cell-culture systems, virus was harvested, gp130 was isolated and peptide mapped. Comparison of gp130 peptide maps of SIVmac142 by computer graphic analysis revealed a variation in relative spot intensity of up to 20%. No major variability of gp130 was observed in SIVmac142 propagated in HUT-78 cells (i.e. without cytopathic effect induction) in up to 60 passages. However, in MT-2 cells, which are lysed by this virus, gp130 exhibited significant variability and displayed six additional fragments in peptide maps after 24 passages. Peptide map of SIVmac142 gp130 obtained after 60 passages in MT-2 cells was comparable to that after 24 passages. Alterations in the intensity of certain spots indicated changes in the composition of the replicating virus population.
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PMID:Structural variability of the external glycoprotein of simian immunodeficiency virus propagated in cell cultures. 250 10

We have documented rare infection of baboons in their native habitat with simian immunodeficiency virus (SIV). Of 124 sera collected from yellow baboons in central Tanzania, two gave high readings by SIVagm ELISA (greater than 1.0) and moderate by SIVmac ELISA (0.5-1.0). These two sera gave strong reactions to the major SIVagm proteins, including gp130, by western blot analysis; their reactivity to SIVmac protein was considerably weaker. Similar testing of 155 sera from olive baboons of Ethiopia revealed no clearly positive sera. Thus, 2 of 279 baboon sera or 0.7% were positive for antibodies to SIV. The strong reactivity of the two positive yellow baboon sera with SIVagm proteins raises questions about whether these animals may have been infected by green monkeys in their native habitat; baboons occasionally prey upon and eat green monkeys. In addition to these two clearly positive samples, one olive baboon serum and one yellow baboon serum reacted only with major gag protein (p24-p26). Continued study of prevalence and diversity of SIV in primates will be important for understanding the history and evolution of primate lentiviruses and, it is hoped, the origins of viruses that cause AIDS in humans.
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PMID:Prevalence of antibodies to SIV in baboons in their native habitat. 254 34

Epitope variability is one of the greatest obstacles to development of synthetic peptide vaccines. Based on a recently described hypervariable epitope (aa 414-434) on the envelope glycoprotein (gp130) to simian immunodeficiency virus (SIVmac142), we have developed a novel approach to account for epitope variability. We have prepared, in a single synthesis, a cocktail of peptides, designated a hypervariable epitope construct (HEC), which collectively represent all the in vivo variability seen in an epitope. The HEC represents permutations of amino acid substitutions found in the epitope and has been able to induce antibodies with enhanced binding to native SIV and broad immunoreactivity to related epitope analogues.
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PMID:Hypervariable epitope constructs as a means of accounting for epitope variability. 752 82

We identified previously a neutralizing epitope in the V2 domain of the simian immunodeficiency virus (SIVmac) external envelope protein. The present study reports identification of five additional linear epitopes of SIVmac (isolate 251) by immunological screening of a peptide library expressed in yeast, using SIVmac-infected macaque sera. Three epitopes were localized in the envelope glycoproteins and the two others in the reverse transcriptase and in the Rev regulatory protein. Antibody response against the four envelope epitopes was monitored for 2 years in 12 macaques experimentally infected by SIVmac251. These four envelope regions represent major immunodominant epitopes of the SIVmac. Two epitopes are located in the V3 domain (a.a. 311-330) of the external gp130 and near the amino terminal part (a.a. 601-619) of the transmembrane gp36, in regions similar to those identified in HIVs, demonstrating immunological similarities between the envelopes of SIVs and HIVs. SIV-specific immunodominant epitopes were also identified in the V1 (a.a. 111-130) and V2 (a.a. 171-190) domains of the external gp130. In particular, antibody response against the V2 neutralizing region seems to play some role in the control of disease progression in SIVmac-infected macaques.
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PMID:Characterization of B-cell epitopes in the envelope glycoproteins of simian immunodeficiency virus. 768 79


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