Epiglycanin-like material obtained by gel filtration column chromatography of glycoproteins removed by proteolysis from viable cells of six TA3-Ha/A.CA hybrid cell lines will be purified by affinity column chromatography. Purified fractions will be examined for carbohydrate and amino acid compositions, as well as hemagglutination inhibitory activities. Glycoprotein material shed into the media (ascites fluid) and isolated after perchloric acid fractionation, in a manner similar to that utilized with TA3-Ha material, will be fractionated by column chromatography. The amounts of purified epiglycanin samples obtained from an equal number of each hybrid cell line and the chemical compositions of these samples will be compared. The topographical features of at least several of the hybrid cells will be examined by scanning electron microscopy. Physiochemical parameters related to the amount and composition of epiglycanin at the surface of each hybrid cell will be plotted against immunological parameters such as allotransplantability and adsorption of H-2a antisera. BIBLIOGRAPHIC REFERENCES: Codington, J.F. Linsley, K.B., and Silber, C.: Removal of Sialic Acids from Glycoproteins by Chemical Methods and Determination of Sialic Acids, Methods in Carbohydrate Chemistry 7: 226-232, 1976. Miller, S.C., Hay, E.D., and Codington, J.F.: Cell Surface Morphology of the Strain Specific TA3-St Compared to Nonstrain-specific TA3-Ha Ascites Adenocarcinoma Cell. J. Cell Biol. 70: 144a, 1976.