Single-cell immune ecosystem and metabolism reprogramming imprinted by psoriasis niche

BACKGROUND: A major challenge of psoriasis is its dysfunctional immune niche. Remarkable gaps remain in understanding how immune cell state transitions are linked to clinical outcomes in psoriasis. Thus, there is a pressing need to discover immunomodulatory programs governing psoriasis progression. METHODS: Here, by using the state-of-the-art single-cell RNA-sequencing (RNA-seq) data, we observed the unique immune cell profile inside the psoriasis niche compared with the normal skins. RESULTS: In detail, the immunosuppressive T cells such as regulatory T (Treg) cells and CTLA4(+) CD8 T cells showed higher infiltration in the psoriasis niche, indicating the immunosuppressive state was imprinted by such disease. Interestingly, unbiased trajectory and pathway enrichment analysis showed that those suppressive T cells potentially showed developmental and metabolic abnormalities. Intercellular crosstalk modeling shows that exhausted CTLA4(+) CD8 T cells can send out cytokine signaling via utilizing CXCL13-CXCR3 ligand-receptor pair. We finally quantified the metabolism profile of T cells and strikingly observed their enhanced metabolic activity. CONCLUSIONS: Taken together, these data highlight cell-type specific reprogramming within the psoriasis microenvironment and provide evidence for immune-related biomarkers of psoriasis clinical outcome. Our work not only revealed the unique immune ecosystem of psoriasis, but also opened new opportunities for targeting immunometabolism in treating such skin diseases.