CCL27 and oral lichen planus: Herein, the present study firstly investigated phenotypical and functional profiles of ILC populations in the peripheral blood of OLP, analyzed their correlation with clinical types and disease severity, furtherly detected levels of signature ILC activators in OLP plasma, and performed in vitro plasma and cytokine stimulation tests, aiming to explore the phenotypic characteristics of ILCs and their correlation with inflammatory cytokines in OLP.