Thermoneutral housing temperature regulates T-regulatory cell function and inhibits ovabumin-induced asthma development in mice.

The change in ambient temperature is one of the risk factors for the aggravation of bronchial asthma (BA). Yet, whether the ambient temperature influences the immune functions associated with allergic asthma remains unknown. In this study, we treated asthmatic mice with standard temperature (ST, 20 °C) or thermoneutral temperature (TT, 30 °C). The results showed that the airway inflammatory cell counts in bronchoalveolar lavage fluid (BALF) and airway hyperresponsiveness (AHR) were significantly reduced in the mice treated with TT as compared with the mice treated with ST. The imbalance of Th1/Th2 response in the lung was improved following housing the mice at TT. In addition, the pulmonary Treg cells were increased in asthmatic mice after TT treatment. The temperature stress (29 °C and 41 °C) drove naïve CD4T cells towards Th2 cells. Our data demonstrate that the change of ambient temperature was a risk factor to aggravate experimental asthma.