Cyclic GMP levels in interferon treated cells

Various types of normal and neoplastic lymphoid cells in culture respond to interferon with elevated cyclic GMP levels. Human pre-T and natural killer cells are more sensitive to this effect than B lymphocytes. Cultured neurons and erythroid cells also show the effect. However, fibroblasts from different origin, although responsive to the antiviral effect of interferon, do not elevate their levels of cyclic GMP. Only fibroblasts from patients with Down's syndrome which are trisomic for chromosome 21 and more sensitive than their normal disomic counterparts to the antiviral action of interferon exhibit enhanced cyclic GMP levels following interferon treatment. These results suggest than an increase in cyclic GMP does not mediate the principal biologic actions of interferon. Further, the inability of certain cell types to increase their cyclic GMP content in response to interferon may reflect differences in their degree of interferon sensitivity rather than an inherent inability to respond to this action of interferon.