Our vivo and vitro research indicates that TREM2 may firstly inhibit the activation of NF-κB pathway by suppressing the expression of TLR4 and MyD88, and then inhibit the activation of NLRP3 inflammasome and its downstream inflammatory cascade and pyroptosis, and finally mitigating the neuroinflammatory and the damage to dopaminergic neurons in PD. Here, TLR4 is linked to Parkinson disease.