Complement-fixing antigens in Burkitt lymphoma cell lines.

The complement-fixing (CF) activity of antigens from cultured Burkitt lymphoma cells was determined by using normal American sera as the source of antibody. Approximately 75% of the sera fixed complement with the positive cell lines. These lines contained the herpes-like virus detectable by electron microscopy. The content of CF antigen depended on the cell line used but appeared to be independent of the number of cells which produced Henle's immunofluorescence (IF) antigen. Only sera that reacted in the IF test also contained CF antibodies to the crude cell extracts.