Expression of an anti-H58A monoclonal antibody recognized molecule in rabbit tonsillar epithelium.

The H58A monoclonal antibody (mAb) recognizes a highly conserved determinant on MHC class I molecules in various species. This mAb was used in immunohistochemical studies to determine the presence of this molecule in rabbit tonsils. The molecule is strongly expressed in all layers but the germinal one, of the stratified epithelium (SSE) of the oral cavity and tonsillar crypt. The expression of this molecule is completely abolished in the lymphoepithelial regions of the crypt epithelium. In cortison-induced immunosuppressed animals, the lymphoepithelium is depleted and gradually transforms to SSE. Consequently, the expression of the H58A mAb recognized molecule reappears. Further studies are needed to determine if this molecule plays any kind of functional role in the formation of lymphoepithelial tissue.