Chemical characterization of murine Ia alloantigens determined by the I-E/I-C subregions of the H-2 complex

Alloantisera directed against the alloantigens determined by the I-E and I-C subregions of the murine major histocompatibility complex precipitate two components that have molecular weights of 35,000 and 29,000. These components, when analyzed by partial NH₂-terminal sequencing, show no homology to two components of similar size determined by the I-A subregion. However, the large chain determined by the murine I-E and/or I-C subregion is homologous to the large chain of the human HLA-D region alloantigen, although the small chains isolated from these two species do not display any such homology.