For example, scRNA-seq data analysis showed that the subpopulation of NK cells expressing SELL, a gene encoding the cell surface adhesion molecule L-selectin, was proliferated in alcohol-induced cirrhotic livers, whereas the subtype of NK cells expressing XCL2 (X-C motif chemokine ligand 2) was enriched in the healthy livers [37]. The gene discussed is XCL2; the disease is alcohol dependence.