JAK3 and alopecia areata: Alopecia areata lesions also exhibit upregulated expression of genes, such as CCL19, IL-2, IL-15/IL-15RA, IL-2RA/IL-2RB, and Janus kinase 3 (JAK3) responsible for T cell migration and activation compared to regions with normal hair growth in alopecia areata patients (Table 2) (136).