One‐dimensional isoelectric focusing and immunoblotting of equine major histocompatibility complex class I antigens

Abstract

The cells of 60 randomly selected Hannoveranian warm-blooded horses were subjected to one-dimensional isoelectric focusing and immunoblotting with a cross-reacting monoclonal antibody (Bo 1) recognizing bovine class I antigens. The banding patterns were correlated with the serologically defined specificities of the ELA-A locus. ELA-A2 was correlated with four bands, while ELA-A5, ELA-W18, ELA-A6, ELA-A14 and ELA-A9 were correlated with a single band each. The complexity of the pattern and additional polymorphic bands which could not be correlated to any of the known ELA specificities may indicate biochemical variants of established serological specificities or still-undetected allelic products of more than one class I locus expressed at the surface of horse cells. Here we present the first description of the biochemical complex polymorphism of equine MHC class I molecules using one-dimensional isoelectric focusing. Direct comparison of biochemical and serological polymorphisms revealed potentials and limitations of both techniques which supplement each other. Their combination will improve and enhance the definition of expressed products of different loci in the ELA class I region.