Biochemical characterization of the T-cell alloantigen RT-6.2.

This study presents the partial molecular characterization of the alloantigenic rat T-cell marker RT-6. In contrast to most lymphocyte surface membrane proteins, RT-6 proved to be resistant to short- term (15 mm) solubilization by T X-100 at 4°, but could be efficiently solubilized by long-tent (16 hr) exposure at 4° or short-term (15 mm) exposure at 37°. SDS-PAGE analyses of RT-6.2 immunoprecipitates under non-reducing conditions revealed two bands with apparent molecular weights of 21,000 and 24,000 (25,000 and 28,000 under reducing conditions). Radiolabelled sugars failed to be incorporated metabolically into RT-6.2, neither endoglycosidase-F and 0-glycanase digestion nor NaOH treatment caused any detectable decrease in the molecular weight of RT-6.2, and RT-6.2 failed to bind to any of a series of agarose-coupled lectins with a wide range of sugar-binding specificities. These observations suggest that RT-6.2 may lack carbohydrate moieties. [ABSTRACT FROM AUTHOR]