Dataset Information

Early-life heterologous rhinovirus infections induce an exaggerated asthma-like phenotype.

ABSTRACT:

Background

Early-life wheezing-associated respiratory tract infection by rhinovirus (RV) is a risk factor for asthma development. Infants are infected with many different RV strains per year.

Objective

We previously showed that RV infection of 6-day-old BALB/c mice induces a mucous metaplasia phenotype that is dependent on type 2 innate lymphoid cells (ILC2s). We hypothesized that early-life RV infection alters the response to subsequent heterologous infection, inducing an exaggerated asthma-like phenotype.

Methods

Wild-type BALB/c mice and Rora^fl/flIl7r^cre mice lacking ILC2s were treated as follows: (1) sham on day 6 of life plus sham on day 13 of life, (2) RV-A1B on day 6 plus sham on day 13, (3) sham on day 6 plus RV-A2 on day 13, and (4) RV-A1B on day 6 plus RV-A2 on day 13.

Results

Mice infected with RV-A1B at day 6 and sham at day 13 showed an increased number of bronchoalveolar lavage eosinophils and increased expression of IL-13 mRNA but not expression of IFN-γ mRNA (which is indicative of a type 2 immune response), whereas mice infected with sham on day 6 and RV-A2 on day 13 of life demonstrated increased IFN-γ expression (which is a mature antiviral response). In contrast, mice infected with RV-A1B on day 6 before RV-A2 infection on day 13 showed increased expression of IL-13, IL-5, Gob5, Muc5b, and Muc5ac mRNA; increased numbers of eosinophils and IL-13-producing ILC2s; and exaggerated mucus metaplasia and airway hyperresponsiveness. Compared with Rora^fl/fl mice, Rora^fl/flIl7r^cre mice showed complete suppression of bronchoalveolar lavage eosinophils and mucous metaplasia.

Conclusion

Early-life RV infection alters the response to subsequent heterologous infection, inducing an intensified asthma-like phenotype that is dependent on ILC2s.

SUBMITTER: Rajput C

PROVIDER: S-EPMC8097639 | biostudies-literature |

REPOSITORIES: biostudies-literature

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