Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0017638 (glioma)
 30,880 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

CD4 and one of the G-protein-coupled receptors (GPCRs) on the cell surface function as a receptor and a coreceptor, respectively, in infection of cells with human and simian immunodeficiency viruses (HIV/SIV). To determine which GPCRs can be coreceptors for HIV (HIV-1 and HIV-2) or SIV infection, several cell lines, including human osteosarcoma HOS-T4 cells and human glioma U87/CD4 cells, have been used. However, these cells often show susceptibilities to some HIV or SIV strains before transduction of GPCRs. The results of this study showed that a CD4-transduced human glioma cell line, NP-2/CD4, a human erythroleukemia cell line, K562/CD4, and a human ovarian cancer cell line, TYK/CD4, were completely resistant to the HIV-1 and HIV-2 strains tested. After transduction of several GPCRs into NP-2/CD4, K562/CD4, or TYK/CD4 cells, NP-2/CD4 cells but not K562/CD4 or TYK/CD4 cells mostly showed expected susceptibilities to several HIV strains. Therefore, an NP-2 cell system would be useful to determine the coreceptor usage of HIV isolates, to find a new coreceptor for HIV/SIV, and to analyze the early stages of HIV/SIV infection.
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PMID:Establishment of a new system for determination of coreceptor usages of HIV based on the human glioma NP-2 cell line. 1032 84

G protein-coupled receptors serve as coreceptors in the infection process of human immunodeficiency virus type-1 (HIV-1), type-2 (HIV-2), and simian immunodeficiency virus (SIV). In this study, we showed that a CXC-CKR, CXCR5/BLR1, is a novel coreceptor for HIV-2, but for neither HIV-1 nor SIV. The expression of CXCR5 was detected by polymerase chain reaction after reverse transcription of cellular mRNA from S+L-HOS/CD4 cells and MT-2 human T cells, and the CXCR5 gene was cloned into an expression vector. S+L-HOS/CD4 cells were susceptible to several HIV-2 strains but not most HIV-1 strains. To examine a coreceptor activity of CXCR5, we used NP-2/CD4, which is a human glioma cell line, NP-2, transduced with the CD4 gene that shows strict resistance to infection with HIV-1, HIV-2, SIVmac, SIVagm, or SIVmnd strain. When CXCR5 was transduced into NP-2/CD4 cells, they became highly susceptible to HIV-2ROD and HIV-2CBL23 strains in a CD4-dependent manner but to not to HIV-1 or SIV strains. Anti-CXCR5 monoclonal antibody and a ligand for CXCR5, BCA-1, inhibited HIV-2 infection to NP-2/CD4/CXCR5 cells. Our findings suggest a possibility that CXCR5/BLR1 serves as a coreceptor for HIV-2 strains in vivo.
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PMID:A CXC chemokine receptor, CXCR5/BLR1, is a novel and specific coreceptor for human immunodeficiency virus type 2. 1060 May 98

Research on HIV vaccines, as well as studies on HIV pathogenesis in human and SIV in the macaque model, require the availability of simple and standardized assays for quantification of neutralizing antibodies to primary virus isolates. We have recently developed and standardized assays using human cell lines engineered to express CD4 and co-receptors for HIV and SIV entry. One cell line originated from a glioma (U87) and the other from an osteosarcoma (HOS). Both cell lines and their derivatives form monolayer cultures, a prerequisite for counting plaques. HIV-infected U87.CD4-CCR5 or -CXCR4 cells form syncytia, that is, plaques that can be stained with hematoxylin and enumerated by light microscopy. In addition to CD4 and co-receptors (most often used CCR5 and CXCR6 by SIV), GHOST(3) cells have been engineered to express the green fluorescent protein following virus infection. Infected cells show green fluorescence and can be enumerated by fluorescence microscopy. Neutralization is determined by the ability of a serum to reduce the number of plaque-forming units (PFU) relative to controls exposed to medium or negative serum. Both assays are run in microtiter format and neutralization is evaluated after 3 d. Intra-assay variation has been used for estimation of the cutoff for neutralization. Testing 15 serum-virus combinations in the U87.CD4 assay and four serum-virus combinations in the GHOST(3) assay revealed that standard deviation of differences ranged from 9.1% to 9.9% in the two assays. This allowed the use of a cutoff >3 SD; that is, 30% neutralization. Virus titration experiments showed that neutralization results were dependent on virus dose and therefore the neutralization assays should be performed with a virus dose of 10-100 PFU/well. The assays have high specificity and reproducibility, and are simple and sensitive high-throughput assays.
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PMID:Plaque-reduction assays for human and simian immunodeficiency virus neutralization. 1606 83