Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.6.4 (chondroitinase)
 2,039 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The role of cell-surface proteoglycans in human immunodeficiency virus (HIV) infection of T-cell lines was investigated. HIV-1-susceptible lymphoblastic T-cell lines, MT-4 and H9, were analyzed for proteoglycan synthesis and found to make heparan sulfate (HS) and chondroitin sulfate proteoglycans. Enzymatic treatment of these cells with heparitinase, but not chondroitinase, significantly prevented HIV-1(IIIB) infection as measured by inhibition of cytopathicity, reverse transcriptase production, and syncytia formation. Sulfation of glycosaminoglycans HS chains was critical to viral entry as shown by inhibition of viral infection with sodium chlorate and its specific reversal with exogenous sulfate addition. Quantitation of direct virus binding to cells showed that treatment of cells with heparitinase inhibited HIV-1 binding to the T-cell surface. Exogenous HS added to cultures inhibited virus infection in a manner analogous to dextran sulfate, further supporting a functional role for HS in HIV-1 binding. These results provide evidence for participation of cell-surface HS proteoglycans in HIV-cell attachment and virus entry.
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PMID:Cell-surface heparan sulfate proteoglycan mediates HIV-1 infection of T-cell lines. 809 45

To investigate the role of cell surface glycosaminoglycans (GAGs), including heparan sulfate (HS), on HIV-1 infection in human T cells, HIV-1 binding and infection were determined after treatment of T-cell lines and CD4+ T cells from normal peripheral blood mononuclear cells (PBMC) with GAG-degrading enzyme or a GAG metabolic sulfation inhibitor. Heparitinase I (hep I) and sodium chlorate prevented binding of HIV-1/IIIB to MT-4 cells as revealed by indirect immunofluorescence procedures, thereby inhibiting infection. Hep I was less effective in the binding inhibition of the macrophage-tropic strain HIV-1/SF162 than that of the T-cell line-tropic strain HIV-1/IIIB. The binding of HIV-1/SF162 was about 100-fold less dependent on cell surface HS than HIV-1/IIIB. Human HTLV-I positive T-cell lines expressed more HS than HTLV-I negative T-cell lines or normal CD4+ T cells when stained with anti-HS mAbs against either native or heparitinase-treated HS. With the exception of endo-beta-galactosidase (endo-beta-gal), GAG-degrading enzymes, including hep I, chondroitinase ABC (chon ABC), chondroitinase AC II (chon AC II) and keratanase, did not prevent the binding of HIV-1/IIIB to CD4+ T cells from normal PBMC. These results indicate that the cell surface HS of human T cells participates in HIV-1 infection by facilitating HIV-1/IIIB binding to MT-4 cells. In particular, the sulfation of HS chains is critical. Since the expression of cell surface HS varies among T cells, which are not consistently sensitive to hep I treatment in HIV-1 binding inhibition, other GAG-like molecules may also be involved.
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PMID:Role of cell surface glycosaminoglycans of human T cells in human immunodeficiency virus type-1 (HIV-1) infection. 898 38