Synthesis of secretory component by human colon cancer cells.

Colon carcinoma, established in long-term tissue culture, has been shown to synthesize secretory component (SC). These molecules can be demonstrated both on the cell surface and in the cytoplasm by immunofluorescence. Regeneration of SC was demonstrable after trypsinization of the cells. In culture, two lines of carcinoma epithelium were shown to incorporate (14C) leucine into newly synthesized SC. These cell lines should provide useful preparations for studying the details of immunoglobulin-SC interactions.