title: Production and secretion of interleukin-1alpha proteins by rat testis.
abstract: The present study characterizes constitutively expressed rat testicular interleukin-1alpha (IL-1alpha) proteins. IL-1 bioactivity of crude testis protein was completely neutralized by IL-1alpha antiserum, IL-1 receptor antagonist, and soluble type I IL-1 receptor. Upon non-denaturating gel permeation chromatography, bioactive IL-1 eluted at molecular sizes of 45, 31, and 17kDa and at charges of pH 5.7 and 6.0 after chromatofocusing. SDS-PAGE/Western blot analysis of proteins extracted from whole testis, seminiferous tubules, interstitial, and seminiferous tubule fluids all demonstrated IL-1alpha immunoreactivity at 45, 24, and 19kDa. Activated macrophages and tissue proteins from endotoxin treated rats showed immunoreactive 31 and 19kDa IL-1alpha. The results indicate that the testis produces three isoforms of IL-1alpha proteins that are secreted into the interstitial compartment and tubular lumen where they may exert paracrine functions. The testicular IL-1alpha isoforms may represent posttranslationally modified precursor, mature IL-1alpha, and a 24-kDa alternate splice form.
authors.affiliation: Pediatric Endocrinology Unit, Q2: 08, Department of Woman and Child Health, Astrid Lindgren Children's Hospital, SE-171 76 Stockholm, Sweden.
authors.forename: Katarina
authors.initials: K
authors.lastname: Gustafsson
authors.forename: Taranum
authors.initials: T
authors.lastname: Sultana
authors.forename: Cecilia K
authors.initials: CK
authors.lastname: Zetterström
authors.forename: Brian P
authors.initials: BP
authors.lastname: Setchell
authors.forename: Arif
authors.initials: A
authors.lastname: Siddiqui
authors.forename: Günther
authors.initials: G
authors.lastname: Weber
authors.forename: Olle
authors.initials: O
authors.lastname: Söder
mesh_terms: D000818:Animals; D002455:Cell Division; D002851:Chromatography, High Pressure Liquid; D004247:DNA / Q000096:biosynthesis; D007375:Interleukin-1 / Q000096:biosynthesis* / Q000302:isolation & purification / Q000378:metabolism; D008297:Male; D051379:Mice; D008970:Molecular Weight; D051381:Rats; D017207:Rats, Sprague-Dawley; D013737:Testis / Q000276:immunology*
chemical_list: D007375:Interleukin-1; D004247:DNA