Furthermore, Th1 secreted cytokine (IFN‐γ) and Th17 secreted cytokine (IL‐17) were both reduced in the OE‐JKAP group, while elevated in the KD‐JKAP group, compared to the NC group; while Th2 secreted cytokine (IL‐10) did not differ among the groups (Fig. 7A‐C); implying JKAP inhibited Th1 and Th17 differentiation in PD. Here, IL17A is linked to Parkinson disease.