Recombinant Anti-CD3 x Anti-HIV-1 gp120 Bispecific Antibody (Bi-nanobody) is designed to be expressed as a VHH from anti-CD3 antibody variable domains fused with a VHH from an anti-HIV-1 gp120 antibody variable domains. It contains a His-tag at the C/N terminus for affinity purification. The BsAb exits as monomer in reducing and non-reducing conditions. This BsAb can retarget T cells to HIV-1 infected cells. It is designed for the research of HIV-1 infection, AIDS therapy.