Recombinant Anti-BAFF x Anti-B7RP1 Bispecific Antibody (scFv-Fc) is formed by fusing two different scFv fragments to the hinge and Fc regions, in which the Fc region are engineered by KIH. Two of scFv moiety has the antibody variable domain of either anti-BAFF specificity or anti-B7RP1 specificity, which produces bivalent IgG-like molecules with desired characteristics of intact antibodies. 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.