Overall, we identified 10 immune cell populations using marker expression patterns (Supplementary Fig. 2b), and found that RDEB skin lesions, in contrast to healthy tissue section, were marked by the presence of neutrophils, B cells, and plasma cells, as well as elevated numbers of activated CD4+ and CD8+ T, regulatory T cells, monocytes/DC, and macrophages (Fig.1d). Here, CD4 is linked to recessive dystrophic epidermolysis bullosa.