Recombinant Anti-BAFF x Anti-B7RP1 Bispecific Antibody (IgG-scFv) is designed to be expressed as a LC and an extended HC with scFv moiety linked to the C terminus. It is a symmetric bispecific and tetravalent molecule, bivalent for each antigen specificity, 2+2 antigen-binding valency. This BsAb can bind and inactivate two ligands simultaneously. It can inhibit B cell survival and T cell costimulation. It is designed for the research of Systemic lupus erythematosus (SLE) therapy.