Further Studies on Surface Antigen of Shope Papilloma Cells: Trypsin Sensitivity

Summary

The surface antigen specific for Shope papilloma virus (SPV) was easily exfoliated by trypsinization. When cells dispersed with 0.25% trypsin were stained by the indirect immunofluorescent technique, the ratio of the cells with specific surface fluorescence did not exceed 5%. However, when ceils dispersed with 0.02% ethylenediaminetetraacetate and those frown on coverslips were stained by similar procedures, over 15 and 50% of the cells, respectively, fluoresced. The trypsin sensitivity of the antigen thus detected suggests that the SPV-induced new surface antigen is a protein or protein-bound substance. The cytotoxic test was not sensitive enough to detect antigen remaining on the surface of cells dispersed with 0.25% trypsin.