New approaches to the chemical characterization of membrane molecules.

Recognition of the H-2D and H-2K cell surface molecules plays an integral role in the cell mediated cytolysis of virally infected or chemically modified cells by immune cytotoxic thymus derived cells. Previously, technical difficulties have made structural studies on these membrane molecules extremely difficult. We present micromethods based on detergent solubilization and indirect immunoprecipitation which have allowed us to determine the amino acid sequence of the N-terminal portion of four H-2D and H-2K molecules. Application of these microsequencing methods to the determination of the detailed structure of these molecules will allow us to assess their involvement as targets in immune surveillance. This kind of approach will facilitate detailed chemical analysis of a variety of membrane molecules of interest in developmental and tumor biology.