Isoprinosine enhances the activation of sensitized lymphocytes by Epstein-Barr virus antigens

Abstract

Isoprinosine, a synthetic purine derivative and a potentially useful immunostimulating agent, was tested for its ability to enhance lymphocyte responses to Epstein-Barr virus (EBV) antigens and to autologous EBV-transformed lymphocytes. Isoprinosine significantly enhanced the response of sensitized lymphocytes (i.e. from EBV-seropositive individuals) to EBV antigens, while it has no effect on the lack of response of unsensitized lymphocytes (i.e. from EBV-seronegative individuals) to these antigens. In addition, isoprinosine enhanced lymphocytes response to autologous EBV-transformed cells, and potentiated the generation of cytotoxic lymphocytes. From these observations, and since immunosuppression is commonly observed in EBV-associated malignancies and other EBV-induced disorders, it may be important to point out that the use of isoprinosine as an immunostimulating agent in patients with these diseases deserves serious consideration.