A concentration‐dependent increase in TLR2 and TLR4 expression was observed upon exposure to HI‐AF. TLR2 was upregulated by both live AF and HI‐AF. TLR4 was upregulated by HI‐AF but downregulated by live AFAF spores stimulated increased secretion of Th2 cytokines IL25, IL33 and TSLP. IL25 and IL33 induced by live AF was higher than that of HI‐AF. IL25 induction was higher than other cytokines. The gene discussed is TLR4; the disease is atrial fibrillation.