title: Interleukin (IL)-4 induces leukocyte infiltration in vivo by an indirect mechanism.
abstract: Interleukin (IL)-4 is a cytokine known mainly for its anti-inflammatory activity. Using the in vivo murine air pouch model, we found that IL-4 significantly increased the number of leukocytes after 9 hours of treatment, consisting mainly of neutrophil (60%) and monocytic (40%) cell populations. Using an antibody array, we found that the expression of several analytes (predominantly CCL2) was increased by IL-4 before the arrival of leukocytes. The IL-4-induced expression of CCL-2 was confirmed by ELISA. Air pouch resident lining cells were harvested and were found to express IL-4Ralpha. CCL2 mRNA expression was monitored in lining cells, cells isolated from the air pouch skin, in RAW264.7 macrophage and in epithelial Mode-K cells and its expression was increased in response to IL-4 in all conditions. We conclude that IL-4 can attract leukocytes in vivo by an indirect mechanism involving the production of several analytes by, at least, resident cells.
authors.affiliation: INRS-Institut Armand-Frappier, Université du Québec, Québec, Canada.
authors.forename: Claude
authors.initials: C
authors.lastname: Ratthé
authors.forename: Jamila
authors.initials: J
authors.lastname: Ennaciri
authors.forename: David M
authors.initials: DM
authors.lastname: Garcês Gonçalves
authors.forename: Sonia
authors.initials: S
authors.lastname: Chiasson
authors.forename: Denis
authors.initials: D
authors.lastname: Girard
mesh_terms: D000818:Animals; D002465:Cell Movement / Q000187:drug effects; D002478:Cells, Cultured; D018932:Chemokine CCL2 / Q000096:biosynthesis / Q000235:genetics; D006801:Humans; D015847:Interleukin-4 / Q000494:pharmacology*; D007962:Leukocytes / Q000187:drug effects* / Q000502:physiology; D051379:Mice; D008810:Mice, Inbred C57BL; D012333:RNA, Messenger / Q000032:analysis; D019948:Receptors, Interleukin-4 / Q000096:biosynthesis
chemical_list: D018932:Chemokine CCL2; D012333:RNA, Messenger; D019948:Receptors, Interleukin-4; D015847:Interleukin-4