Some properties of the soluble (S) antigen of cultured lymphoblastoid cell lines

Summary

Extracts of human lymphoblastoid cell lines derived from infectious mononucleosis patients and from normal individuals yielded an antigen, which was immunologically closely related, if not identical, to the soluble (S) antigen present in cell lines derived from Burkitt lymphoma patients. This antigen was found in both the EB virus-positive and EB virus-negative lines.

The S antigen was stable at 4° C over the period of one week, but at 37° C at least 50% of activity was lost in 24 hours. When heated for 30 minutes at 56° C or at higher temperatures, the antigen titer was reduced but some activity was still preserved even after heating at 80° C. The antigen was found to be trypsinsensitive but it was stable over the range of pH 5.0 to 8.2. No evidence was obtained thus far that more than one antigen reactive with human sera was present in the preparations tested.

The highest S antigen titers in EB 3 cells were formed after cultivation of these cells at 32° C, in P3J cells at 37° C. The P3J cells grew well at 40°C; at this temperature both the synthesis of S antigen and the formation of EB virus antigens detectable by immunofluorescence were preserved even after long-term cultivation. The cultivation of cells in arginine deprived media did not result in enhancement of either S antigen titer or percentage of cells positive by immunofluorescence.