ITIH4 and Alzheimer disease: Like other IAIP family members, ITIH4 also has systemic anti‐inflammatory properties in some complex diseases, including Alzheimer's disease, acute ischemic stroke, etc.23, 24With regard to RA, previous studies find that citrullinated form of ITIH4 is differentially expressed in joints of RA patients and it fluctuates with disease activity score, which indicates that citrullinated ITIH4 may participate in the inflammation response of RA.25, 26, 27