Epstein-Barr herpesvirus infection: inhibition by immunologically induced mediators with interferon-like properties.

When sensitized leukocytes were re-exposed to EBV antigen or to tuberculin-purified protein derivatives, they produced lymphokines, including the migration inhibition factor, which inhibited the migration of guinea-pig peritoneal exudate cells, and other lymphokines with the characteristics of interferon, which inhibited EBV-induced transformation and EBV superinfection of target cells. Unsensitized leucocytes from sero-negative adults and from neonates did not produce lymphokines when challenged with the antigens. This indicates that cell-mediated immunity and its associated soluble mediators may be involved in the control of EBV infection and that the interferon release assay is a useful in vitro correlate for the study of cellular immunity to EBV.