Regarding AAV-hα-Syn or Cntnap4+/− mice showed no obvious effects on other serum cytokines, included IL-2, IL-10, and IL-17, we would like to say, on one hand, in some studies, these cytokines were reported unaltered in the serum of PD patients [59]; on the other hand, serum cytokines may not reflect the inflammatory state in the brain. This evidence concerns the gene IL2 and Parkinson disease.