We have utilized in vitro marrow culture techniques to evaluate the cytotoxicity for granulocytic progenitor cells of two highly purified human leukocyte interferon preparations. Concentration- and time-related decrements in granulocytic colony-forming capacity in agar occurred with human and mouse marrow. Although mouse marrow cells were less sensitive than were human cells, these data indicat...

Poly(A) containing mRNA prepared from poly(rI)-poly(rC)-induced human fibroblasts stimulated [14C]leucine incorporation into protein in wheat germ cell-free extracts. For the translation of interferon mRNA into a biologically active product, the presence of spermine was essential. The protein synthesized in vitro fulfilled the criteria for human interferon--namely, its antiviral activity was sp...