Recombinant Anti-CD89 x Anti-S. pneumoniae Bispecific Antibody (Tandem scFv) is designed to be expressed as a scFv from an anti-CD89 antibody variable domains fused with a scFv from an anti-S. pneumoniae 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 retarget NK cells to genus plasmodium. It is designed for the research of S. pneumoniae infection therapy.