The glycopeptides produced by pronase digestion of two H-2K, two H-2D, and three Ia glycoprotein antigens were examined for size and charge. The glycopeptides derived from all of the antigens examined were found to have m.w. of 3250 ± 200 daltons with a similar and variable composition of sialic acid residues. These data, when combined with the similarity in monosaccharide incorporation, suggest that the general parameters of the carbohydrate structure of the Ia glycoproteins from different I subregions and H-2 glycoproteins are highly similar if not identical.
This work was supported by United States Public Health Service Grants AI-07289, AI-10702, and Grant IM-77 from the American Cancer Society.
A preliminary report of these studies has appeared elsewhere (31).