Recombinant Anti-CD55 x Anti-HLA-A Bispecific Antibody (scDiabody-Fc) is a fusion protein of two scDiabodies with an Fc region. In single-chain Diabodies, an additional connecting linker is introduced between chains of the anti-CD55/anti-HLA-A diabody. The scDiabody with two specificities is further fused to the Fc domain to form BsAb with 2+2 antigen-binding valency. This BsAb can recruit complements to tumor cells. It is designed for the research of Renal cell cancer (RCC); Solid tumors therapy.