IL17A and asthma: The results showed that SH improved the Treg/Th17 cell imbalance and reduced airway inflammation by enhancing the frequency of CD4+, CD25+, FoxP3+, and Treg cells and the secretion of the pro-inflammatory cytokine interleukin-10 (IL-10), as well as reducing the generation of Th17 cells and interleukin-17A (IL-17A), which suggests that SH is beneficial for the treatment of asthma [37].