Human cutaneous antigen-presenting cells (APCs) (APCs)

Human cutaneous antigen-presenting cells (APCs) are a specialized group of immune cells located within the skin layers, including epidermal Langerhans cells and various dermal dendritic cell subsets (Nestle et al., 2009, Nature Reviews Immunology). These cells serve as the primary sentinels of the peripheral immune system, responsible for capturing exogenous antigens, migrating to draining lymph nodes, and presenting these antigens to naive T cells to initiate adaptive immune responses (Kissenpfennig & Malissen, 2006, Biological Reviews). In clinical practice, cutaneous APCs are central to the pathophysiology of inflammatory skin diseases such as atopic dermatitis and psoriasis, where they contribute to chronic T-cell activation (StatPearls, Antigen Presenting Cells). They are also key targets for topical immunomodulators; for instance, Imiquimod acts as a TLR7 agonist to activate these cells for treating viral warts and basal cell carcinoma, while calcineurin inhibitors like Tacrolimus suppress their function to alleviate eczema (PubChem, Imiquimod; FDA, Protopic). Because this term refers to a diverse cellular population rather than a single protein, it is classified as a cellular target rather than a specific molecular receptor.

Other names

Skin-resident antigen-presenting cellsCutaneous APCsDermal dendritic cellsLangerhans cellsSkin APCs

Drugs targeting these cells typically act by modulating their maturation, migration, or ability to present antigens and secrete pro-inflammatory cytokines (e.g., TLR7 agonism by Imiquimod or calcineurin inhibition by Tacrolimus).