Evidence for a Persistent Viral Infection in a Cell Line Derived from Burkitt's Lymphoma

Henle, Gertrude (Children's Hospital of Philadelphia, Philadelphia, Pa.),and Werner Henle . Evidence for a persistent viral infection in a cell line derived from Burkitt's lymphoma. J. Bacteriol.89: 252–258. 1965.—Exposure of a cell line (EB2) derived from Burkitt's lymphoma to vesicular stomatitis (VSV) and certain other viruses revealed a marked resistance of the cultures to infection. Intact, but not disintegrated lymphoma cells induced resistance to VSV in human embryonic kidney, amnion and diploid, as well as in green monkey kidney cells employed as feeder layers. A line of rabbit kidney or Earle's strain L cells was not protected under similar conditions. Depending upon the number of EB2 cells initially transferred, resistance developed within 1 day or in more than 2 weeks. Cell-free media collected from cultures of EB2 cells in the presence or absence of feeder layers of human cells were capable of conferring rapid protection against VSV to human-cell cultures but not to L cells. The protective principle complies with present criteria for an interferon. The results are compatible with the suggestion that EB2 cultures are latently infected with an as yet unidentified virus.