title: IL-1 receptor antagonist (IL-1ra) augments IL-2-induced pulmonary vascular leak.
abstract: Interleukin-2 (IL-2) therapy is dose limited by a severe vascular leak with resulting systemic and pulmonary toxicity. Although recognized as a mediator of septic shock and vascular leak, the relative role of IL-1 in IL-2 toxicity is unclear. We evaluated the effect of IL-1 receptor antagonist (IL-1ra) on IL-2 lethality, pulmonary vascular leak, and treatment of pulmonary metastases in a murine model. In vivo induction of mRNA for IL-1 alpha was evaluated in liver by Northern blots after 0, 5, 8, and 11 doses of IL-2 in C3H/HEN mice. The expression index for the IL-1 alpha gene increased from 0.16 to 0.74 after 5 doses of IL-2, and further increased to 1.04 after 11 doses of IL-2. C3H/HEN mice (n = 56) were randomized to receive phosphate-buffered saline (PBS), IL-1ra high dose (HD), or IL-1ra low dose (LD) by continuous subcutaneous infusion via Alzet mini-pumps. The biologic effectiveness of the dose and administration of IL-1ra was determined by the ability to block IL-1-induced IL-6 production in vivo. Mean serum IL-6 levels 3 hr after intraperitoneal IL-1 alpha (10 micrograms/kg) were: PBS, 3730 +/- 526 (mean +/- SEM pg/ml); IL-1ra (LD), 1156 +/- 398; and IL-1ra (HD), 594 +/- 30 (P < 0.01, IL-1ra HD or LD vs PBS). Pulmonary vascular leak was measured by iv I125 albumin after 8 doses of IL-2 (100,000 U ip q 8 hr).(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Surgical Metabolism Section, National Cancer Institutes, National Institutes of Health, Bethesda, Maryland 20894.
authors.forename: A K
authors.initials: AK
authors.lastname: Thom
authors.forename: D L
authors.initials: DL
authors.lastname: Fraker
authors.forename: J A
authors.initials: JA
authors.lastname: Norton
mesh_terms: D000818:Animals; D002199:Capillary Permeability / Q000187:drug effects*; D004357:Drug Synergism; D005260:Female; D015870:Gene Expression; D007375:Interleukin-1 / Q000235:genetics; D007376:Interleukin-2 / Q000494:pharmacology*; D015850:Interleukin-6 / Q000378:metabolism; D008175:Lung Neoplasms / Q000517:prevention & control / Q000556:secondary; D051379:Mice; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D011652:Pulmonary Circulation / Q000187:drug effects*; D012333:RNA, Messenger / Q000378:metabolism; D017472:Receptors, Interleukin-1 / Q000037:antagonists & inhibitors*
chemical_list: D007375:Interleukin-1; D007376:Interleukin-2; D015850:Interleukin-6; D012333:RNA, Messenger; D017472:Receptors, Interleukin-1