T200 cell surface glycoprotein of the mouse. Polymorphism defined by the Ly-5 system of alloantigens.

The cell line BW5147, and a mutant T200-negative cell line derived from BW5147, were studed by immunoprecipitation and peptide mapping, with xenogeneic monoclonal anti-T200 serum and with Ly-5 alloantiserum. It appears that the Ly-5 system defines a structural polymorphism of the cell surface glycoprotein T200, and that the monoclonal anti-T200 serum defines a feature of T200 that is common to mice of both Ly-5a and Ly-5b genotypes and may be invariable in the species.