Characterisation of a monoclonal antibody recognising the CD3ε chain of the bovine T cell receptor complex

We describe the characterisation of a monoclonal antibody (mAb), designated MM1A, which reacts with an antigen molecule on the surface of bovine αβ and γδTcR+ T cells. The mAb immunoprecipitated a series of polypeptides of 21 kDa, 22 kDa, 32 kDa, 36 kDa and 44 kDa which is consistent with it recognising the TcR/CD3 complex. COS cells, transfected with a cDNA encoding the bovine CD3ε chain, reacted with mAb MM1A indicating that the epitope recognised is on the ε chain of the complex and confirming that the mAb recognised bovine CD3.