In:
PLOS ONE, Public Library of Science (PLoS), Vol. 18, No. 1 ( 2023-1-27), p. e0279498-
Abstract:
Over the past 50 years, the prevalence of allergic respiratory diseases has been increasing. The Hygiene hypothesis explains this progression by the decrease in the bio-diversity of early microbial exposure. This study aims to evaluate the effect of early-life farm exposure on airway hyperresponsiveness and cough hypersensitivity in an allergic airway inflammation rabbit model. Method A specific environment was applied to pregnant rabbits and their offspring until six weeks after birth. Rabbits were housed in a pathogen-free zone for the control group and a calf barn for the farm group. At the end of the specific environmental exposure, both groups were then housed in a conventional zone and then sensitized to ovalbumin. Ten days after sensitization, the rabbit pups received ovalbumin aerosols to provoke airway inflammation. Sensitization to ovalbumin was assessed by specific IgE assay. Cough sensitivity was assessed by mechanical stimulation of the trachea, and bronchial reactivity was assessed by methacholine challenge. The farm environment was characterized by endotoxin measurement. Results A total of 38 rabbit pups were included (18 in the farm group). Endotoxin levels in the farm environment varied from 30 to 1854 EU.m -3 . There was no significant difference in specific IgE values to ovalbumin (p = 0.826) between the two groups. The mechanical threshold to elicit a cough did not differ between the two groups (p = 0.492). There was no difference in the number of cough (p = 0.270) or the intensity of ventilatory responses (p = 0.735). After adjusting for age and weight, there was no difference in respiratory resistance before and after methacholine challenge. Conclusion Early exposure to the calf barn did not affect cough sensitivity or bronchial reactivity in ovalbumin-sensitized rabbits. These results suggest that not all farm environments protect against asthma and atopy. Continuous exposure to several sources of microbial diversity is probably needed.
Type of Medium:
Online Resource
ISSN:
1932-6203
DOI:
10.1371/journal.pone.0279498
DOI:
10.1371/journal.pone.0279498.g001
DOI:
10.1371/journal.pone.0279498.g002
DOI:
10.1371/journal.pone.0279498.g003
DOI:
10.1371/journal.pone.0279498.t001
DOI:
10.1371/journal.pone.0279498.t002
DOI:
10.1371/journal.pone.0279498.t003
DOI:
10.1371/journal.pone.0279498.t004
DOI:
10.1371/journal.pone.0279498.s001
DOI:
10.1371/journal.pone.0279498.s002
DOI:
10.1371/journal.pone.0279498.s003
DOI:
10.1371/journal.pone.0279498.s004
DOI:
10.1371/journal.pone.0279498.s005
DOI:
10.1371/journal.pone.0279498.s006
DOI:
10.1371/journal.pone.0279498.r001
DOI:
10.1371/journal.pone.0279498.r002
DOI:
10.1371/journal.pone.0279498.r003
DOI:
10.1371/journal.pone.0279498.r004
Language:
English
Publisher:
Public Library of Science (PLoS)
Publication Date:
2023
detail.hit.zdb_id:
2267670-3
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