A lymphocyte antigen encoded by a locus closely linked to H-3 on the second chromosome of the mouse.

A monoclonal antibody has been developed that recognizes a mouse lymphocyte antigen, Ly-23, that is controlled by an H-3 histocompatibility complex-linked gene on the second chromosome. Competitive binding experiments demonstrate that this antigen is distinct from the polymorphic beta 2-microglobulin antigen, which also is encoded by a gene closely linked to H-3. The strain distribution pattern differs from that of the beta 2-microglobulin polymorphism, and recombination apparently has separated the genes for these two antigens during the derivation of one recombinant inbred line. However, the R1E/TL8X line of cells, which lacks beta 2-microglobulin, is negative for the Ly-23 antigen, although the control R1.1 line is positive. The H-2 locus affects the expression of both the Ly-23 and beta 2-microglobulin antigens.