Recombinant Anti-CD55 x Anti-HLA-A Bispecific Antibody (Tandem scFv) is designed to be expressed as a scFv from an anti-CD55 antibody variable domains fused with a scFv from an anti-HLA-A antibody variable domains. It contains a His-tag at the C/N terminus for affinity purification. The BsAb exits as monomer in reducing and non-reducing conditions. This BsAb can recruit complements to tumor cells. It is designed for the research of Renal cell cancer (RCC); Solid tumors therapy.