Production of porcine interleukin-2 and its biological and antigenic relationships with human interleukin-2.

A lymphokine obtained from PHA-stimulated porcine blood leukocytes was found to induce the growth of IL2-dependent murine cells: this factor was therefore considered as the porcine lymphokine analogous to IL2. PHA was found to induce higher amounts of IL2 than Con A. Preculture of porcine PBL or addition of indomethacin enhanced IL2 production, suggesting the existence of a prostaglandin-mediated inhibition of IL2 production in fresh PBL cultures. Porcine IL2 could also promote the growth of activated porcine cells whereas it was inactive on human lymphoblastoid cells. A neutralizing polyclonal anti-human IL2 antiserum was also unable to neutralize porcine IL2. These results indicate therefore, that no biological and antigenic cross-reactivities are demonstrable between human and porcine IL2.