Recombinant Anti-BAFF x Anti-B7RP1 Bispecific Antibody (Minibody) is designed to be expressed as the anti-BAFF scFv fused to N-terminus of Knob-CH3 domain and the anti-B7RP1 scFv to the Hole-CH3 domain, or vice versa. The CH3 domains are further stabilized by C-terminal disulfide bonds. 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.