title: Partial depletion of natural gut flora by antibiotic aggravates collagen induced arthritis (CIA) in mice.
abstract: BACKGROUND
  Rheumatoid arthritis (RA) is a chronic inflammatory disease that affects about 1% of the adult population and occurs twice as frequently among women than men. At present it is accepted that pathogenesis of RA is based on inflammatory response mediated by CD4(+) Th1 and Th17 lymphocytes. The most commonly applied model imitating RA is the collagen induced arthritis (CIA). A growing evidence shows that there is a correlation between microbial dysbiosis and human pathology which includes autoimmunity, allergic diseases, obesity, inflammatory bowel disease (IBD), metabolic syndrome.
  
  
  METHODS
  Collagen induced arthritis was used to study influence of natural gut flora on course of rheumatoid arthritis.
  
  
  RESULTS
  Current work employing CIA model showed that partial depletion of natural gut flora with orally administered antibiotic Baytril (enrofloxacin) aggravates disease severity when compared to control mice. Observed partial depletion of both aerobic and anaerobic bacteria did not affect animal body weight. Additionally, in vitro study showed increased production of IFN-? and IL-17A and decreased release of IL-4 by axillary lymph node cells (ALNC) isolated from mice treated with antibiotic and induced CIA when compared to positive control. Furthermore, treatment with antibiotic prior to CIA induction results in augmented production of IFN-?, IL-17A and IL-6 by mesenteric lymph node cells (MLNC).
  
  
  CONCLUSIONS
  Presented data suggest that alteration of gut microbiota via use of enrofloxacin may play a role in modulating arthritis symptom severity in this mouse model.
authors.affiliation: Department of Medical Biology, Jagiellonian University College of Medicine, Kraków, Poland.
authors.forename: Iwona
authors.initials: I
authors.lastname: Dorożyńska
authors.affiliation: Department of Medical Biology, Jagiellonian University College of Medicine, Kraków, Poland. Electronic address: mmszczep@cyf-kr.edu.pl.
authors.forename: Monika
authors.initials: M
authors.lastname: Majewska-Szczepanik
authors.affiliation: Department of Medical Biology, Jagiellonian University College of Medicine, Kraków, Poland.
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Marcińska
authors.affiliation: Department of Medical Biology, Jagiellonian University College of Medicine, Kraków, Poland.
authors.forename: Marian
authors.initials: M
authors.lastname: Szczepanik
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001169:Arthritis, Experimental / Q000276:immunology*; D000077422:Enrofloxacin; D024841:Fluoroquinolones / Q000494:pharmacology; D007422:Intestines / Q000382:microbiology*; D008297:Male; D051379:Mice; D008811:Mice, Inbred DBA; D018417:Th1 Cells / Q000276:immunology; D058504:Th17 Cells / Q000276:immunology; D016212:Transforming Growth Factor beta / Q000096:biosynthesis
chemical_list: D000900:Anti-Bacterial Agents; D024841:Fluoroquinolones; D016212:Transforming Growth Factor beta; D000077422:Enrofloxacin
keywords: Antibiotic; Collagen induced arthritis; Cytokines; Microbiota