Recombinant Anti-CD55 x Anti-HLA-A Bispecific Antibody (Tandem Fab) is designed to be expressed as three chains derived from the variable domains of anti-CD55 and anti-HLA-A parental antibodies. It contains a His-tag for affinity purification. And the two Fd regions are connected by a flexible linker. This BsAb can recruit complements to tumor cells. It is designed for the research of Renal cell cancer (RCC); Solid tumors therapy.