Epidermal thickness and proportion of epidermal, rather than dermal, CD8+IL17A+ and CD8+CD44+ cells were notably increased in IMQ-treated mice that received AAV2 H2-D1 compared with mice administered with AAV-Ctrl (Supplementary Fig. S10j–m), suggesting that continuous MHC-I antigen presentation in KCs is crucial for epidermal CD8+ T cell differentiation and cytokines release, but it does not affect the function of CD8+ T cell in dermis. This evidence concerns the gene IL17A and dry eye syndrome.