Modification of acute and late-phase allergic responses to ovalbumin with lipopolysaccharide

Tulic, M. K., Holt, P. G. and Sly, P. D. (2002) Modification of acute and late-phase allergic responses to ovalbumin with lipopolysaccharide. International Archives of Allergy and Immunology, 129 2: 119-128. doi:10.1159/000065881

Author Tulic, M. K.
Holt, P. G.
Sly, P. D.
Title Modification of acute and late-phase allergic responses to ovalbumin with lipopolysaccharide
Journal name International Archives of Allergy and Immunology   Check publisher's open access policy
ISSN 1018-2438
Publication date 2002-10
Sub-type Article (original research)
DOI 10.1159/000065881
Volume 129
Issue 2
Start page 119
End page 128
Total pages 10
Place of publication Basel, Switzerland
Publisher S. Karger
Language eng
Formatted abstract
Background: We have previously shown that lipopolysaccharide (LPS) exposure in sensitised animals 18 h after ovalbumin (OVA) challenge inhibits OVA-induced airway hyper-responsiveness (AHR). In the present study, we investigated the effect of LPS on OVA-induced acute and late-phase allergic responses in sensitised rats when challenged with OVA.

Methods: Rats were sensitised with OVA and 11 days later challenged with 1% OVA in the presence or absence of LPS (0.5-50 μg/ml) given in the same nebulizer. Acute responses to OVA were measured each minute for 30 min after challenge. In a separate group of animals, late-phase responses to OVA were determined at 24 h. At the end of each study, Evans blue dye was injected and animals sacrificed 30 min later. Bronchoalveolar lavage was obtained to monitor inflammatory cell migration and microvascular leakage.

Results: OVA challenge in sensitised animals produced an acute response with changes in lung mechanics peaking 10.0 ± 0.9 min after OVA and returning to baseline within 30 min. This was followed 24 h later by increased responses to methacholine chloride (MCh), inflammatory cell influx and increased Evans blue leakage into the lungs. Presence of 5 or 50 μg/ml LPS in the nebulizer during OVA challenge altered the kinetics of the acute-phase response, with an immediate decrease in lung function (time to peak decreased from 10.3 ± 1.2 to 1.8 ± 0.2 and 2.2 ± 0.3 min, respectively: p < 0.001, n = 6) and a dose-dependent attenuation of late-phase AHR, cellular influx (n = 5, p < 0.001) and Evans blue leakage (n = 5, p < 0.001) at 24 h.

Conclusions: In summary, co-administration of OVA with LPS modifies both the acute and late-phase responses to the allergen, inducing an earlier acute change in lung function and a dose-dependent inhibition of late-phase responses to the allergen.
Keyword Lipopolysaccharide
Allergic sensitization
Lung inflammation
Q-Index Code C1
Q-Index Status Provisional Code
Institutional Status Non-UQ

Document type: Journal Article
Sub-type: Article (original research)
Collection: Faculty of Health and Behavioural Sciences -- Publications
Version Filter Type
Citation counts: TR Web of Science Citation Count  Cited 26 times in Thomson Reuters Web of Science Article | Citations
Scopus Citation Count Cited 30 times in Scopus Article | Citations
Google Scholar Search Google Scholar
Created: Wed, 17 Nov 2010, 11:54:27 EST