Recombinant Anti-CEA x Anti-TNFα Bispecific Antibody (Tandem scFv-Fc) is designed to be expressed as a homodimer, which has 2+2 antigen-binding valency. This format consists of one Fc region and two tandem scFv fragments, in which the anti-CEA/TNFα tandem scFv is fused to the Fc domain. The engineered fragment format is used to extend the half-life. This BsAb can retarget cytokine (TNFα) to tumor cells. It is designed for the research of Breast cancer; Ovary cancer; Colon cancer; Lung cancer therapy.