Recombinant Anti-CD55 x Anti-HLA-A Bispecific Antibody (scDiabody-CH3) is a fusion protein of two scDiabodies connected together by a CH3 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 fused to each of the CH3 chains to extend half-life. This BsAb can recruit complements to tumor cells. It is designed for the research of Renal cell cancer (RCC); Solid tumors therapy.