Construction of human combinatorial antibody library and screening of monoclonal antibody Fabs to human immunodeficiency virus type I

The heavy chain Fd genes and kappa chain genes of immunoglobulin were ampli fied by RT-PCR from PBL of three volunteer donors with HIV-positive. Phage antibody library was constructed with the Fd genes and kappa chain genes us ing pComb3 as vector. Three-round selection against coated gp120 showed spe cific enrichment of phage antibodies. After the third round selection, 40 o ut of 50 clones exhibited gp120 binding capacity. The specificity of the cl ones was verified by ELISA and competition inhibition ELISA. The VH was der ived from subgroups V-H II and V-H III V-L belonged to subgroups V-kappa I and V-kappa III with DNA sequencing. These results suggest that the antibod ies obtained are specific to gp120.