We have observed the clinical effects of interleukin 2 (IL-2) therapy for Epstein-Barr (EB) virus infection in two children with immunodeficiency syndrome. A 13-year-old boy with Shwachman's syndrome had chronic active EB virus infection. There were defective lymphokine-activated killer (LAK) cell and cytotoxic T lymphocyte (CTL) activities against autologous EB virus-transformed B cells and a marked decrease in IL-2 production. He received recombinant IL-2 (1, 000 U/day) by intra-venous drip infusion for 14 days. There has been a clinical improvement in the development of pneumonia, splenomegaly and exanthema after the therapy. There were, although transient, a decrease in VCA-IgG antibody titers and sero-conversion of EBNA antibody. A 14/12-year-old boy with fatal EB virus infection was treated by adoptive immunotherapy with his own CTL generated against autologous EB virus-transformed B cells in the presence of recombinant IL-2. There were no LAK cell and CTL activities against the EB virus transformed B cells and no IL-2 production. Unfortunately, he died from the preexisting pneumonia soon after the therapy. However, EB virustransformed B cell lines, which had been easily established from his peripheral blood mononuclear cell cultures, were never established after the therapy.
