Induction of circulating soluble tumour necrosis factor receptor and interleukin 1 receptor antagonist following interleukin 1 alpha infusion in humans.

The aim of this study was to investigate circulating levels of tumour necrosis factor soluble receptor p55 (TNFsrp55) and interleukin 1 receptor antagonist (IL-1ra) in cancer patients undergoing treatment with IL-1 alpha. Patients were treated with 0.03 micrograms/kg IL-1 alpha administered intravenously over a 30 min interval daily for five consecutive days. Plasma TNFsrp55 levels rose dramatically and peaked (24.5 +/- 3.6 ng/ml) within 1 h after the first IL-1 alpha infusion. Thereafter, the levels rapidly declined and reached baseline levels within 24 h. The increases observed on days 3 and 5 of treatment were less pronounced but the reductions in peak levels were not statistically significant. IL-1ra levels increased less abruptly after an IL-1 alpha infusion than did TNFsrp55 levels and peaked (25.3 +/- 5.1 ng/ml) within 2 h of the start of the IL-1 alpha infusion. Levels then rapidly declined reaching baseline values within 24 h. As with TNFsrp55 levels, peak IL-1ra levels observed on days 3 and 5 of treatment were less than those measured on day 1. IL-1 alpha and IL-1 beta levels were consistently below the threshold of detection of the RIAs employed in these studies. Likewise, with the exception of a single time point in one of the four patients studied, TNF-alpha was undetectable in all plasma samples assayed.(ABSTRACT TRUNCATED AT 250 WORDS)