Membrane molecules determined by the H 2 associated immune response region: Isolation and some properties

Membrane associated molecules that are probably glucoproteins could be specifically precipitated from NP 40 detergent solubilized extracts of radiolabeled mouse spleen or lymph node cells by antisera produced in congenic strain combinations differing only in the Ir gene region which is linked to the H 2 genes. These Ir region products were designated Lna (lymph node antigen) to conform to previous serological work. Sodium dodecyl sulfate polyacrylamide gel electrophoresis of undreduced specific immune precipitates revealed the presence of a possible dimer form, while reduced samples showed only a single peak equivalent to 30,000 daltons. Thus the Lna molecules are clearly distinct from the H 2D and H 2K molecules, which are about 45,000 daltons. Anti Lna antibodies of different specificity can be present in a single serum; there were at least two separate antigen molecules present in one haplotype tested.