Recombinant Anti-CCR3 x Anti-CD300 Bispecific Antibody (F(ab')2-scFv2) is designed to be expressed as two chains combined via a hinge region. The scFv of the anti-CCR3 specificity is fused to the C terminus of the anti-CD300 Fab fragment, or vice versa. This format comprises four binding sites (two same scFv regions and two same Fab fragments), two for each antigen. This BsAb canreduce eosinophil signaling, inhibit bronchoalveolar lavage fluid inflammation, eosinophil, mast cell mediator release and reverse lung inflammation. It is designed for the research of Asthma therapy.