ABSTRACT
Objective:To determine the binding ability of ~V-1 V3 loop to target cells.Methods:V3 loop peptides(V3-HBIO,V3-ADA,V3-89.6)derived from different HIV-1 strains LIIB(X4-nopic),ADA(R5-tmpic),89.6(R5X4-tropic) and the biotinylated V3-BH1O(biotin-BHIO) and V3 -ADA( biotin-ADA) were synthesized. The binding of the biotinylated V3 peptides to cells and the binding targets were analyzed using flow cytometry. Results:V3 BH10 can bind to a wide range of cell lines, while bio-ADA scarcely binds to the monocytes derived from periperal blood mononuclear cells.Antibody anti-CXCR4 binding to cells blocked by V3 -BH10 and biotin-BH1O binding was blocked by protease inhibitors. The binding of V3-BH10 could be significantly enhanced by V3-BHlO but by neither V3-89.6 nor V3-ADA.Conclusion:The binding ability of the V3 loop derived from diverse HIV- I strains are different. The V3 loop derived from HIV-1 X4-tropic strain directly binds to a wide range of cell lines, the binding targets are multiple including at least coreceptor and proteases. The V3 loop derived from R5 -tropic strain ADA does scarcely.