Human lymphocyte production of corticotropin and endorphin-like substances: association with leukocyte interferon.

Abstract

Human leukocyte interferon (hIFN-.alpha.) preparations contain immunologically and biologically recognizable endorphin and corticotropin-like (ACTH-like) activities. The ACTH bioactivity was demonstrable only after pepsin or acid treatment. Highly purified hIFN-.alpha. was composed of 2 molecular species of interferon (18,500 and 23,000 daltons). Endorphin activity was associated with both of these molecules. Pepsin treatment of the 23,000-dalton but not the 18,500-dalton hIFN-.alpha. broke down into the 18,500-dalton form and ACTH (4500 daltons). The ACTH derived from hIFN-.alpha. by pepsin digestion comigrated with a purified ACTH standard in sodium dodecylsulfate-polyacrylamide gel electrophoresis. hIFN-.alpha.-producing lymphocytes showed positive immunofluorescence after staining with highly specific antisera to ACTH.alpha.-(1-13) and .gamma.-endorphin. Essentially 100% of the human peripheral lymphocytes were capable of producing both ACTH and .gamma.-endorphin-related substances, presumably associated with hIFN-.alpha.. A circuit between the immune and neuroendocrine systems which involves neuroendocrine hormone-like substances, some of which are associated with hIFN-.alpha., is suggested.