Dendritic cell subsets in alopecia areata: focus on plasmacytoid dendritic cells and Langerhans cells in immune imbalance and therapeutic implications

INTRODUCTION: T cells are well-established as the primary effector cells in AA, emerging evidence indicates that dendritic cells (DCs) play important upstream regulatory roles in disease initiation and progression. AREAS COVERED: This narrative review systematically synthesizes relevant studies from the PubMed database published up to May 2026, dissecting the dual roles of distinct DC subsets in maintaining hair follicle immune privilege and driving autoimmune cascade, along with core molecular pathways. It also analyses DC-related mechanisms of standard therapies and emerging DC-targeted therapeutic strategies. EXPERT OPINION: DCs play important roles in the complex immunopathological network of AA. DC-targeted precision therapies hold substantial potential to overcome the limitations of broad immunosuppression and restore long-term follicular immune homeostasis, with single-cell multi-omics technologies enabling further mechanistic and translational advances.