PRODUCTION OF INFECTIVE EPSTEIN-BARR VIRUS IN A BURKITT LYMPHOMA CELL LINE, P3HR-1

Abstract

Production of infective Epstein-Barr (EB) virus in the culture medium of a Burkitt lymphoma cell line, P3HR-1, was examined. Determination of the infectious titer of the virus was followed by detection of EB virus-directed new (N) antigen formation in the cells of a clonal line (C-6) derived from the NC-37 cell line and infected with EB virus. The percentages of N antigen-forming cells in these cultures were roughly parallel to the dose of the inoculated virus. The amounts of infective virus produced were higher with incubation of the cells at 33° than that at 37°. The amounts produced were also higher in cultures with a low density of cells than in that with a high density of cells. Culture of P3HR-1 cells with a larger fraction of virion antigen-bearing cells yielded a larger amount of the infective virus. Stability of the infectivity at various test temperatures showed that the virus is most stable at -80°, but was less stable at-20° than that at 4° which was comparable to that at 33°. Infectivity was lost most rapidly at 37°. From these results, ideal culture conditions for production of the virus were proposed and nature of the virus was discussed.