Generation and characterization of monoclonal antibodies to human PCTAIRE 3

Monoclonal antibodies specific for the unique N-terminal domain of the PCTAIRE 3 protein kinase have been produced and characterized. The specificity of these antibodies has been assessed by ELISA, Western blot, and immunoflorescence techniques. These reagents are specific for recombinant PCTAIRE 3 of human origin and do not cross-react with PCTAIRE 1 or PCTAIRE 2, despite the high homology between members of the PCTAIRE subfamily of cdc2-like kinases. Immunoblotting of transfected cells reveals that all of the antibodies recognize both isoforms of the PCTAIRE 3 kinase. Epitope mapping reveals three distinct classes of PCTAIRE 3 antibodies that recognize different sites within an immunodominant region of the N-terminal domain of the protein. The creation of highly specific PCTAIRE 3 monoclonal reagents will be useful for assessing the native distribution and function of this protein.