RESULTS: In our study, increased expression of TLR2 was found in OVA-challenged lung tissues. TLR2-/- mice treated with OVA exhibited decreased serum OVA-specific IgE, airway inflammation, and goblet cell metaplasia compared with OVA-challenged WT mice. Meanwhile, the level of inflammatory and autophagic signaling activation was lower in OVA-treated TLR2-/- versus WT mice. OVA-induced JNK activation was also reduced in TLR2-/- mice. Interestingly, inhibition of JNK by SP600125 in WT mice similarly attenuated the level of serum OVA-specific IgE, OVA-induced airway inflammation and goblet cell metaplasia but not found in TLR2-/- mice in comparision with vehicle-treated TLR2-/- mice. At the same time, JNK inhibition affected inflammatory and autophagic signaling activation to some extent.