Interferon assay anomaly variation of interferon response with cell type and sialic acid content

Human interferon derived from leukocytes and cultured fibroblast sources has been compared by assay in two human cell systems. The ratio of the activities of the two interferon preparations differed markedly in two assay systems. Neuraminidase treatment had no effect on the activity of either interferon in the more sensitive system but reduced the activity of the fibroblast material in the second system so that the resulting ratio of activities approximated that seen in the first assay system.