title: Role of interleukin-6 in immune complex induced models of vascular injury.
abstract: Previous studies have suggested that Interleukin-6 (IL-6) acts as a marker of vasculitis. To determine the role of IL-6 in vasculitis we utilized two models of immune complex induced vascular injury (dermal Arthus and acute pulmonary alveolitis) in IL-6 deficient (IL-6(-/-)) and IL-6 sufficient (IL-6(+/+)) mice. Plasma and bronchoalveolar lavage (BAL) levels of IL-6 were elevated in the injured IL-6(+/+) mice with acute alveolitis and in the plasma of IL-6(+/+) mice with dermal Arthus vasculitis. While, IL-6 levels in IL-6(-/-) mice were near or below the levels of detection. Histological examination of the intensity of vascular injury response demonstrated no significant differences between IL-6(-/-) and IL6(+/+) mice. More specifically, lung permeability (total protein in the BAL) in the lung injury model in IL-6(-/-) mice was the same as injured IL-6(+/+) mice. As a corollary, assessment of vascular permeability in both models was the same in the IL-6(-/-) as the IL-6(+/+) mice. Quantification of leukocyte influx into the injured tissues in both models also revealed no differences between the IL-6(-/-) and IL-6(+/+) mice. These data demonstrate that while IL-6 is upregulated in acute vascular injury it does not appear to be critical in the development of the vascular inflammatory response.
authors.affiliation: Department of Pathology, University of Michigan Medical School, 7520 MSRB I, 1301 Catherine Rd., Ann Arbor, MI 48109, USA.
authors.forename: Shannon D
authors.initials: SD
authors.lastname: McClintock
authors.forename: Adam G
authors.initials: AG
authors.lastname: Barron
authors.forename: Eric W
authors.initials: EW
authors.lastname: Olle
authors.forename: Michael P
authors.initials: MP
authors.lastname: Deogracias
authors.forename: Roscoe L
authors.initials: RL
authors.lastname: Warner
authors.forename: Mark
authors.initials: M
authors.lastname: Opp
authors.forename: Kent J
authors.initials: KJ
authors.lastname: Johnson
mesh_terms: D000818:Animals; D000936:Antigen-Antibody Complex / Q000276:immunology*; D001183:Arthus Reaction / Q000276:immunology; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry; D002199:Capillary Permeability; D004195:Disease Models, Animal; D015850:Interleukin-6 / Q000172:deficiency / Q000378:metabolism*; D007962:Leukocytes / Q000473:pathology; D008168:Lung / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D010539:Permeability; D011014:Pneumonia / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D011506:Proteins / Q000032:analysis; D011650:Pulmonary Alveoli; D015854:Up-Regulation; D014657:Vasculitis / Q000276:immunology* / Q000378:metabolism / Q000473:pathology
chemical_list: D000936:Antigen-Antibody Complex; D015850:Interleukin-6; D011506:Proteins