Rabbit antisera prepared against interferon produced in human fibroblast cell cultures stimulated with poly(I) -poly(C) neutralized the activity of interferon preparations produced in various human fibroblast cultures stimulated either with poly(I) poly(C) or with viruses. However, these antisera showed no detectable neutralizing activity against interferon produced in cultures of human leukocytes. On the other hand, most rabbit antisera against the human leukocyte interferon were active in neutralizing both homologous interferon and fibroblast interferons. A preparation of antiserum against leukocyte interferon, active against both leukocyte and fibroblast interferons, was shown by affinity chromatography to have two distinct antibody populations, one of which was specific for the fibroblast interferon. We conclude that the heterologous neutralizing activity of sera from rabbits immunized with leukocyte interferon is likely to be due to the presence of two antigenic species of interferon. The major antigenic species of leukocyte interferon preparations (designated "Le") is distinct from human fibroblast interferon. The minor species of leukocyte interferon ("F") is either identical with, or closely related to, interferon produced in human fibroblast cultures.

No abstract

Cell-mediated immunity to cytomegalovirus (CMV) was determined in congenitally infected children and their mothers by use of assays for CMV-specific lymphocyte blastogenesis and interferon production. Six viruric children responded poorly in both assays. Two older nonviruric children responded in the blastogenesis assay, and lymphocytes from one of them produced interferon. Mothers of older children usually responded in the blastogenesis assay, but only one of them produced interferon. Mothers whose infected infants were younger than nine months of age responded poorly in both assays, while control seropositive postpartum women generally responded normally. The cell-mediated immune defects detected in this study may play a role in the pathogenesis of congenital CMV infection.