ISG15 and skin disorder: Consistently, the heatmap and results of qRT-PCR showed that GSDMD deficiency considerably impaired the expression of genes involved in antigen presentation, including H2-Dmb1, H2-Dma, H2-Ab1, Tap2, Cd86, Ifitm2, Isg15, Ifitm1, and S100a8. Studies have shown that S00A8 can promote the expression of MHC and co-stimulatory molecules, thereby enhancing the antigen presentation capacity of antigen-presenting cells during arthritis and dermatitis (Kessel et al, 2013; Petersen et al, 2013).