The Effect of JAK Inhibitor on Survival, Anagen Re-Entry, and Hair Follicle Immune Privilege Restoration in Human Dermal Papilla Cells

The study explored the impact of ruxolitinib, a JAK1/2 inhibitor, on human dermal papilla cells (hDPCs) in the context of alopecia areata (AA). Ruxolitinib was found to maintain cell viability, activate the Wnt/ß-catenin signaling pathway, suppress DKK1 transcription, and reverse the expression of inflammatory molecules induced by interferon gamma (IFN-γ), such as caspase-1, IL-1ß, IL-15, and IL-18. Additionally, it stimulated the expression of growth factors like FGF7 and protected against the IFN-γ-induced collapse of hair-follicle immune privilege. The study concluded that ruxolitinib could potentially treat AA by modulating inflammatory changes, stimulating anagen-re-entry signals, and preserving hair-follicle immune privilege. However, the experiments had a small sample size (n = 3), suggesting that further research with larger sample sizes is necessary to validate these results.