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A Koito

Publications and source records attributed to A Koito.

25 records · Page 2Linked to original sources

Characterization of a human immunodeficiency virus neutralizing monoclonal antibody and mapping of the neutralizing epitope.

A monoclonal antibody was produced to the exterior envelope glycoprotein (gp120) of the human T-cell lymphotropic virus (HTLV)-IIIB isolate of the human immunodeficiency virus (HIV). This antibody binds to gp120 of HTLV-IIIB and lymphadenopathy-associated virus type 1 (LAV-1) and to the surface of HTLV-IIIB- and LAV-1-infected cells, neutralizes infection by cell-free virus, and prevents fusion of virus-infected cells. In contrast, it does not bind, or weakly binds, the envelope of four heterologous HIV isolates and does not neutralize heterologous isolates HTLV-IIIRF and HTLV-IIIMN. The antibody-binding site was mapped to a 24-amino-acid segment, using recombinant and synthetic segments of HTLV-IIIB gp120. This site is within a segment of amino acid variability known to contain the major neutralizing epitopes (S. D. Putney, T. J. Matthews, W. G. Robey, D. L. Lynn, M. Robert-Guroff, W. T. Mueller, A. J. Langlois, J. Ghrayeb, S. R. Petteway, K. J. Weinhold, P. J. Fischinger, F. Wong-Staal, R. C. Gallo, and D. P. Bolognesi, Science 234:1392-1395, 1986). These results localize an epitope of HIV type-specific neutralization and suggest that neutralizing antibodies may be effective in controlling cell-associated, as well as cell-free, virus infection.

Amino Acid Sequence↗

Evaluation of the safety of blood products with respect to human immunodeficiency virus infection by using an HTLV-I-infected cell line (SKT-1B).

Human immunodeficiency virus (HIV), the etiologic agent of acquired immunodeficiency syndrome (AIDS), was rapidly cytopathic to SKT-1B, a cell line established from a patient with adult T cell leukemia, in vitro. This cytopathic effect was preceded by the expression of HIV antigen, defined with a monoclonal antibody (mAb) specific for the core protein (p24) of HIV. SKT-1B is highly susceptible to HIV as compared with MT-2 and H9 cells. HIV is known to be transmitted via blood products, and thus we examined whether or not currently used procedures for manufacturing blood products are safe by using SKT-1B. Lyophilized HIV was heated at 65 degrees for time periods in the range of 10 min to 48 hr, and the infectivity was examined. The results showed that heating at 65 degrees for less than 2 hr was not sufficient to inactivate HIV, but the virus heated for 48 hr had no effect on SKT-1B. In addition, HIV completely lost its infectivity on sulfonation, which is commonly used to avoid anaphylactic shock on intravenous infusion of human immunoglobulins. These findings indicate that blood products manufactured by currently used procedures are probably safe with respect to HIV infection.

Antigens, Neoplasm↗

Characterization of three monoclonal antibodies (VAK3-5) that identify p24, core protein of human immunodeficiency virus, and its precursors.

VAK3, VAK4 and VAK5 monoclonal antibodies (mAbs) were raised by using disrupted purified human immunodeficiency virus (HIV) as an antigen. These mAbs exclusively reacted with an HIV-infected cell line, H9/HIV, and did not react with human T cell lymphotropic virus (HTLV)-I or -II infected cell lines. Strip radioimmunoassay based on the Western blotting technique revealed that these mAbs recognize a single band that corresponds to a 24-kd (p24) core protein of HIV when disrupted viruses were used as antigens. When cell lysates of H9/HIV were used as antigens, these mAbs gave two bands with molecular weights of 40 kd (p40) and 57 kd (p57) in addition to p24. VAK5-conjugated Sepharose 4B beads precipitated non-glycosylated proteins, p24, p40 and p57 from [L-35S]methionine-labeled H9/HIV. P57 and p40 appear to be a precursor and an intermediate precursor of p24, respectively. Purified IgG of VAK3 and VAK4, and the serum from an individual infected with HIV inhibited the binding of VAK5 mAb to HIV. These findings suggest that p24 of HIV contains structure(s) with strong antigenicity.

Animals↗

Preliminary evidence for inhibitory effect of glycyrrhizin on HIV replication in patients with AIDS.

Glycyrrhizin (GL) at a dose of 400-1600 mg/day (7.2-30.8 mg/kg/day) was administered intravenously for a period of more than a month, on 6 separate occasions, to 3 hemophiliacs with acquired immune deficiency syndrome (AIDS). Human immunodeficiency virus type 1 (HIV-1) p24 antigen was detected at the beginning of 5 of the 6 treatment courses. Viral antigen was not detected at the end of or during 3 of the 5 treatment courses and decreased to a low level following the 2 other courses. These findings suggest that GL might inhibit HIV-1 replication in vivo.

Acquired Immunodeficiency Syndrome↗