Abstract
Background: Several childhood asthma risk loci that relate to immune function have been identified by genome-wide association studies (GWAS), but the underlying mechanisms remain unknown. Objective: Here, we examined whether perturbed innate immune responses mediate the association between known genetic risk variants and development of childhood asthma. Methods: Peripheral blood mononuclear cells from 336 six-month-old infants from the Copenhagen Prospective Studies on Asthma in Childhood (COPSAC2000) cohort were stimulated in vitro with six different innate ligands (LPS, CpG, poly(I:C), R848, HDMAPP and aluminium hydroxide together with low levels of LPS) followed by quantification of 18 released cytokines and chemokines 40 h after the stimulations. The innate immune response profiles were decomposed by principal component (PC) analysis, and PC1-5 were used in mediation analyses of the effect of 25 known genetic risk variants on childhood asthma until age 7. Results: The effects of two variants from the 17q21 locus (rs7216389, rs2305480) on asthma and exacerbation risk were significantly mediated by immune parameters induced in response to ligands mimicking intracellular colonization; bacterial DNA (CpG) and double-stranded viral RNA (poly(I:C)). The Th17 and innate lymphoid cell type 3-amplifying cytokine IL-23 was the most prominent cytokine involved. Conclusion: The 17q21 effect on childhood asthma and exacerbations was partly mediated by deregulation of IL-23 in response to intracellular microbial ligands, which may suggest ineffective clearance of intracellular pathogens in the lungs.
Originalsprog | Engelsk |
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Tidsskrift | Clinical and Experimental Allergy |
Vol/bind | 51 |
Udgave nummer | 7 |
Sider (fra-til) | 892-901 |
Antal sider | 10 |
ISSN | 0954-7894 |
DOI | |
Status | Udgivet - jul. 2021 |
Udgivet eksternt | Ja |