Chronic bronchial allergic inflammation increases alveolar liquid clearance by TNF-alpha -dependent mechanism.
Bronchial inflammation in allergic asthma is associated with active exudation from the bronchial tree into the interstitial space of both mucosa and submucosa. The aim of this study was to evaluate epithelial and endothelial permeability as well as alveolar fluid movement in a model of chronic allergic inflammation in Brown-Norway rats sensitized and challenged with ovalbumin (OA). Control groups were challenged with saline solution (C), and rats were immunized by OA but not challenged (Se). Lung sections showed a marked inflammatory infiltrate associated with perivascular and peribronchiolar edema in OA. To measure alveolar liquid clearance, a 5% bovine albumin solution with 1 microCi of (125)I-labeled human albumin was instilled into the air spaces. Alveolar-capillary barrier permeability was evaluated by intravascular injection of 1 microCi of (131)I-labeled albumin. Endothelial permeability was significantly increased in OA, from 0.08 +/- 0.01 in the C group to 0.19 +/- 0.03 in OA group (P < 0.05). Final-to-initial protein ratio was also statistically higher in OA (1.6 +/- 0.05) compared with C (1.38 +/- 0.03, P = 0.01) and Se groups (1.42 +/- 0.03, P = 0.04). Administration of anti-tumor necrosis factor-alpha antibodies within the instillate significantly decreased this ratio (1.32 +/- 0.08, P = 0.003 vs. OA). To conclude, we demonstrated a tumor necrosis factor-alpha-dependent increase in alveolar fluid movement in a model of severe bronchial allergic inflammation associated with endothelial and epithelial leakage.
Tillie-Leblond
Isabelle
I
Institut National de la Santé et de la Recherche Médicale U416, Institut Pasteur de Lille, 59019 Lille, France.
Guery
Benoit P H
BP
Janin
Anne
A
Leberre
Rozenn
R
Just
Nicolas
N
Pittet
Jean-Francois
JF
Tonnel
Andre-Bernard
AB
Gosset
Philippe
P
D000418:Albumins / Q000493:pharmacokinetics; D000818:Animals; D015824:Blood-Air Barrier; D001826:Body Fluids / Q000378:metabolism; D001991:Bronchitis / Q000276:immunology* / Q000378:metabolism* / Q000473:pathology; D002196:Capillaries / Q000378:metabolism; D002199:Capillary Permeability; D002417:Cattle; D002908:Chronic Disease; D006801:Humans; D006967:Hypersensitivity / Q000150:complications*; D007114:Immunization; D007073:Immunoglobulin E / Q000378:metabolism; D008168:Lung / Q000378:metabolism; D008297:Male; D010047:Ovalbumin / Q000276:immunology; D011650:Pulmonary Alveoli / Q000098:blood supply / Q000378:metabolism*; D051381:Rats; D011914:Rats, Inbred BN; D014409:Tumor Necrosis Factor-alpha / Q000502:physiology*
D000418:Albumins; D014409:Tumor Necrosis Factor-alpha; D007073:Immunoglobulin E; D010047:Ovalbumin