title: Evidence for the activation of blood complement in Sephadex beads-induced lung inflammation in guinea pigs.
abstract: OBJECTIVE
  This study evaluated the complement activation in guinea pigs that were given an intravenous injection of Sephadex and its correlation with markers of the development of inflammation.
  
  
  METHODS
  Dunkin Hartley guinea pigs (250-300 g) were used. Whole blood was collected by heart puncture in a sodium citrate solution (0.315 g/ml) for complement measurements. Complement activation was measured using a colorimetric haemolytic assay. Bronchoalveolar lavages (BAL) were performed to monitor cell infiltration and inflammation was monitored by measurements of eosinophil peroxidase (EPO), histamine, beta-glucuronidase, albumin and total proteins in the BAL fluid.
  
  
  METHODS
  Guinea pigs were pre-treated with aprotinin (40000 IKU/kg) 30 min before they were given an intravenous injection of Sephadex beads (24 mg/kg). Carboxymethyl (CM)-Sephadex (24 mg/kg) was administered alone.
  
  
  RESULTS
  Sephadex beads activated the complement system in vitro (14.12+/-2.29 U/ml) and in vivo (9.95+/-0.08 U/ml) reaching a peak 6 h after the injection. This activation was accompanied by other characteristic features of inflammation such as leukocyte infiltration and activation. Both CM-Sephadex and aprotinin reduced the blood complement activation and eosinophil infiltration/activation observed.
  
  
  CONCLUSIONS
  Our results strongly suggest that complement is involved in the cascade of events leading to the inflammatory state observed in guinea pig following the intravenous injection of Sephadex beads.
authors.affiliation: Institut de Pharmacologie de Sherbrooke, Faculté de Médecine, Université de Sherbrooke, QC, Canada.
authors.forename: J F
authors.initials: JF
authors.lastname: Blain
authors.forename: K
authors.initials: K
authors.lastname: Maghni
authors.forename: S
authors.initials: S
authors.lastname: Pelletier
authors.forename: P
authors.initials: P
authors.lastname: Sirois
mesh_terms: D000818:Animals; D007611:Aprotinin / Q000494:pharmacology; D003167:Complement Activation; D003911:Dextrans / Q000494:pharmacology*; D006168:Guinea Pigs; D011014:Pneumonia / Q000209:etiology*
chemical_list: D003911:Dextrans; C025614:sephadex; D007611:Aprotinin