Background: Autoimmune mechanisms have important roles in the pathogenesis of alopecia areata (AA). Objective: This study aimed to evaluate the exact biological and clinical importance of immunogenes in AA patients using bioinformatic methods. Methods: Five AA scalp gene expression profiles were obtained from the Gene Expression Omnibus database. Differentially-expressed genes (DEGs) between AA and control groups were identified. An immune-related gene diagnostic signature (IRGDS) was established by protein-protein interaction network analysis, least absolute shrinkage and selection operator and logistic regression analysis. Results: A total of 102 immune-related DEGs were identified. We developed an IRGDS composed of CD8A, CSF1R and CXCL10 for AA molecular pathological assessment and diagnosis (area under the receiver operating characteristic curve [AUC]=0.962). We also validated the diagnostic value of the IRGDS in an external cohort (AUC=0.955). Patients with high IRGDS scores presented with a higher abundance of immune cell infiltration and expression of genes associated with immune recruitment and immune activation, suggesting adverse biological alterations. Conclusion In our study, an IRGDS model with accurately diagnostic capacity for AA was established, and biological alterations were deciphered in AA. The IRGDS may be used as an auxiliary diagnostic marker for AA.

BACKGROUND:Autophagy has become a rapidly developing research hotspot in the biomedical fields.Many researchers are actively exploring the molecular regulatory mechanism of autophagy in a variety of diseases.However,the role of autophagy in hair growth is still unknown. OBJECTIVE:To review the current research progress and application value of autophagy in hair growth and regeneration,to understand the role of autophagy in hair growth,to explore the pathogenesis of autophagy in pathological hair loss,and to provide new ideas for the study of drugs for hair loss. METHODS:Using"hair follicle growth,hair growth,hair regeneration,autophagy associated proteins,autophagy activity,autophagy associated genes,autophagy"as Chinese search terms and"hair growth,hair follicle,hair regeneration,autophagy"as English search terms,PubMed and CNKI databases were searched.The research progress on autophagy,hair growth and the role of autophagy in hair growth in and outside China in recent years was reviewed and summarized.Articles incompatible with the subject content of the paper were excluded.Finally,78 articles were included for the result analysis. RESULTS AND CONCLUSION:(1)Autophagy is a normal metabolic process in eukaryotes with complex molecular mechanisms and functional properties,which is beneficial to cell survival and cell death.(2)Alopecia-related diseases are associated with changes in autophagy activity,which can regulate hair growth cycle.Knockout or overexpression of autophagy-related genes can change the state of hair growth.Multiple autophagy related signaling pathways have been found to be related to hair follicle growth.Activators or inhibitors of autophagy can be used to treat or prevent hair loss.