Toll-like receptor 7 function is reduced in adolescents with asthma

作者：Roponen M; Yerkovich S T; Hollams E; Sly P D; Holt P G; Upham J W^*

来源：European Respiratory Journal, 2010, 35(1): 64-71.

DOI：10.1183/09031936.00172008

• Asthma
• innate immunity
• Toll-like receptor
• virus

Anti-viral innate immune responses may be impaired in asthma, although the mechanisms are not well understood. Toll-like receptors (TLRs) 7 and 3 are particularly relevant for initiating responses to common respiratory viruses, as they recognise single-stranded viral RNA and double-stranded viral RNA, respectively. The aim of the present study was to investigate TLR7 and TLR3 function in 14-yr-old adolescents with asthma.
Blood mononuclear cells obtained from 17 atopic asthmatics, 29 atopic, non-asthmatics and 21 healthy, non-atopic individuals, were stimulated with the TLR7 agonist imiquimod and the TLR3 agonist poly I:C. Expression of anti-viral molecules was measured by real-time PCR. Concentrations of interferon-gamma-inducible cytokine protein (IP)-10 and interleukin (IL)-6 were measured by ELISA.
TLR7-induced myxovirus resistance protein A and 2'5' oligoadenylate synthetase mRNA expression and protein levels of IP-10 were significantly lower in asthma subjects compared with healthy subjects (p=0.041, p=0.003 and p=0.001 respectively). There was a significant negative correlation between total serum immunoglobulin E and IP-10 following TLR7 stimulation. However, TLR3-induced responses did not vary with asthma or atopy. IL-10 mRNA and IL-6 protein synthesis were similar in asthmatic and control subjects. In conclusion, TLR7 function is reduced in adolescents with asthma and this may contribute to susceptibility to respiratory viral infections.

• 出版日期2010-1