title: Exogenous interleukin-16 inhibits antigen-induced airway hyper-reactivity, eosinophilia and Th2-type cytokine production in mice.
abstract: BACKGROUND
  IL-16 has been described as a natural soluble CD4-ligand with immunosuppressive effects in vitro. However, little is known about the effect of IL-16 on immune responses in vivo.
  
  
  OBJECTIVE
  In the present study, we examined the effect of IL-16 administration in a murine model of allergic asthma. Next, we determined whether these effects were mediated by modulation of CD4+ T lymphocytes.
  
  
  RESULTS
  Intraperitoneal administration of IL-16 completely inhibits antigen-induced airway hyper-responsiveness and largely decreases the number of eosinophils in bronchoalveolar lavage fluid (> 90%) and airway tissue of ovalbumin-sensitized and challenged mice. Firstly, it appears that thoracic lymph node cells isolated from in vivo IL-16-treated ovalbumin-challenged animals produce less IL-4 (77%) and IL-5 (85%) upon antigenic re-stimulation, when compared to vehicle-treated mice. Secondly, pre-incubation of lymphocytes with IL-16 in vitro reduces antigen-induced proliferation (55%) and Th2-type cytokine production (IL-4; 56%, IL-5; 77%). Thirdly, the presence of IL-16 during priming cultures of TCR transgenic T cells (DO11.10), reduces IL-4 (33%) and IL-5 (35%), but not IL-10 and IFNgamma levels upon re-stimulation.
  
  
  CONCLUSIONS
  It can be concluded that IL-16 has potent immunosuppressive effects on a Th2dominated allergic airway response.
authors.affiliation: Department of Pharmacology and Pathophysiology, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands.
authors.forename: J J
authors.initials: JJ
authors.lastname: De Bie
authors.forename: E H
authors.initials: EH
authors.lastname: Jonker
authors.forename: P A J
authors.initials: PA
authors.lastname: Henricks
authors.forename: J
authors.initials: J
authors.lastname: Hoevenaars
authors.forename: F F
authors.initials: FF
authors.lastname: Little
authors.forename: W W
authors.initials: WW
authors.lastname: Cruikshank
authors.forename: F P
authors.initials: FP
authors.lastname: Nijkamp
authors.forename: A J M
authors.initials: AJ
authors.lastname: Van Oosterhout
mesh_terms: D000818:Animals; D000941:Antigens; D001249:Asthma / Q000276:immunology*; D016535:Bronchial Hyperreactivity / Q000276:immunology*; D002454:Cell Differentiation / Q000187:drug effects; D016207:Cytokines / Q000096:biosynthesis*; D004802:Eosinophilia / Q000276:immunology*; D007073:Immunoglobulin E / Q000097:blood; D007371:Interferon-gamma / Q000276:immunology; D019410:Interleukin-16 / Q000494:pharmacology*; D008168:Lung / Q000276:immunology; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D023421:Models, Animal; D010047:Ovalbumin; D018418:Th2 Cells / Q000276:immunology*
chemical_list: D000941:Antigens; D016207:Cytokines; D019410:Interleukin-16; D007073:Immunoglobulin E; D007371:Interferon-gamma; D010047:Ovalbumin