Development of Monoclonal Antibodies Specific to Either CD300A R111 or CD300A Q111 or Both.

CD300A is a member of the CD300 immunoglobulin (Ig)-like receptor family consisting of eight molecules in humans, all of which contain one Ig-like domain in the extracellular portion. Upon binding its ligand phosphatidylserine or phosphatidylethanolamine, CD300A mediates an inhibitory signal through the immunoreceptor tyrosine-based inhibitory motif in the cytoplasmic portion. The CD300 family molecules are highly homologous to each other. In addition, CD300A has a single nucleotide polymorphism (rs2272111), which is a nonsense mutation encoding glutamine (CD300A Q111 ) instead of arginine (CD300A R111 ) at residue 111 in the Ig-like domain of CD300A. In this study, we successfully generated monoclonal antibodies (mAbs) specific to either CD300A R111 or CD300A Q111 or both. These mAbs are useful for the analysis of CD300A genotype by flow cytometry and the development of an antibody drug for the treatment of various diseases.