title: Vasoactive intestinal peptide stimulates T lymphocytes to release IL-5 in murine schistosomiasis mansoni infection.
abstract: In murine schistosomiasis, granulomas form around ova deposited in the liver and intestines of infected mice. The granulomas have eosinophils that produce vasoactive intestinal peptide (VIP) and T cells that display VIP receptors. IL-5 is a lymphokine important for the development and maturation of eosinophils. It seemed plausible that VIP, released from eosinophils, may interact with lymphocyte VIP receptors and modulate IL-5 production as part of a feedback regulatory circuit. Thus, we determined whether granuloma T cells make IL-5 and whether VIP modulates IL-5 production. Isolated granuloma cells enriched for T lymphocytes spontaneously released IL-5. Culture of these cells in the presence of VIP increased IL-5 secretion. Spleen cells were also studied. Spleen cells from infected mice did not spontaneously release IL-5 or express IL-5 mRNA and VIP did not stimulate these resting spleen cells to produce this IL. However, these cells did express IL-5 mRNA and secreted IL-5 in response to Con A or soluble egg Ag. VIP could not appreciably modulate IL-5 release when cells were cultured with VIP and the Ag or mitogen. Spleen cells washed free of Con A ceased IL-5 secretion within 24 h. These preactivated splenic T cells resumed vigorous IL-5 secretion in response to either Con A or VIP. Yet only Con A prominently induced IL-5 mRNA expression. VIP was an effective stimulus at concentrations equal to or above the kDa of the VIP receptor on both splenic and granuloma T cells (10(-8) M). It is concluded that, in murine schistosomiasis, VIP invokes IL-5 release from activated T cells that are not undergoing immediate TCR stimulation.
authors.affiliation: Department of Internal Medicine, University of Iowa College of Medicine, Iowa City 52242.
authors.forename: R C
authors.initials: RC
authors.lastname: Mathew
authors.forename: G A
authors.initials: GA
authors.lastname: Cook
authors.forename: A M
authors.initials: AM
authors.lastname: Blum
authors.forename: A
authors.initials: A
authors.lastname: Metwali
authors.forename: R
authors.initials: R
authors.lastname: Felman
authors.forename: J V
authors.initials: JV
authors.lastname: Weinstock
mesh_terms: D000818:Animals; D000947:Antigens, Helminth / Q000276:immunology; D003208:Concanavalin A / Q000494:pharmacology; D004804:Eosinophils / Q000378:metabolism; D005260:Female; D015870:Gene Expression; D006099:Granuloma / Q000276:immunology; D015848:Interleukin-5 / Q000378:metabolism*; D008213:Lymphocyte Activation; D051379:Mice; D008808:Mice, Inbred CBA; D012333:RNA, Messenger / Q000235:genetics; D012555:Schistosomiasis mansoni / Q000276:immunology*; D013154:Spleen / Q000503:physiopathology; D013601:T-Lymphocytes / Q000378:metabolism*; D014660:Vasoactive Intestinal Peptide / Q000494:pharmacology*
chemical_list: D000947:Antigens, Helminth; D015848:Interleukin-5; D012333:RNA, Messenger; D003208:Concanavalin A; D014660:Vasoactive Intestinal Peptide