Production and characterization of interferon from endothelial cells.

The capacity of cultured bovine aortic, capillary, and corneal endothelial cells as well as of human umbilical cord endothelial cells to produce interferon (IFN) was investigated. The endothelial cells of the two species produced significant amounts of IFN in response to various viruses and poly (I) poly (C). The IFN produced by human umbilical cord endothelial cells was a mixture of alpha- and beta-IFN, as determined by neutralization with antibodies directed against these two types of IFNs as well as by measuring the antiviral activity on heterologous cells. Bovine endothelial cells also produced a mixture of at least two IFN subspecies, one of them labile at pH 2 and active on human cells and the other stable at pH 2 and inactive on human cells.