Additive effect of tunicamycin and dextran sulfate on the binding of monoclonal antibody to the V2 domain of the envelope glycoprotein 120 of human immunodeficiency virus type 1

Using flow cytometry or immunoprecipitation analysis in cells chronically infected with HIV-1 IIIB Supt-1, we noticed an additive effect of tunicamycin and low molecular weight dextran (LMDS) on the binding of the G3-4 monoclonal antibody to monomeric and oligomeric forms of glycoprotein 120 (gp120). The inhibition of glycosylation by tunicamycin reduced the number of monomeric and oligomeric forms of gp120. The inhibition of the binding of the G3-4 antibody to monomeric and oligomeric forms of gp120 was more pronounced in the presence of LMDS. We also found that the G3-4 antibody can not recognise the nascent polypeptide chain of the envelope glycoprotein.