Recombinant Anti-TG x Anti-TPO 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-TG/TPO tandem scFv is fused to the Fc domain. The engineered fragment format is used to extend the half-life. This BsAb can bind two antigens simultaneously and block the synthesis of thyroid hormones. It is designed for the research of Autoimmune thyroid disease therapy.