Langerhans cell (LC) (LC)

Langerhans cells (LCs) are a specialized subset of dendritic cells residing in the epidermis of the skin and various mucosal tissues (PubMed: PMID 28434687). They function as professional antigen-presenting cells, characterized by the presence of Birbeck granules and the expression of the C-type lectin receptor Langerin (CD207) (UniProt: P70199). In the context of peanut allergy, LCs are the primary target for epicutaneous immunotherapy (EPIT), where they capture peanut allergens applied to the skin via patches (DBV Technologies). Once the allergen is internalized, LCs migrate to regional lymph nodes and present the processed peptides to naive T cells (PubMed: PMID 30143313). This process is designed to shift the immune response from a Th2-mediated allergic profile toward a regulatory T cell (Treg) profile, thereby inducing clinical desensitization and long-term tolerance (PubMed: PMID 30143313). Drugs like Viaskin Peanut leverage this cellular mechanism to treat peanut-allergic patients by delivering microgram amounts of allergen to the superficial layers of the skin without entering the bloodstream directly (ClinicalTrials.gov: NCT01675882).

Other names

Epidermal dendritic cellCD207+ dendritic cellLangerin-positive cellBirbeck granule-containing cell

Epicutaneous immunotherapy (EPIT) utilizes Langerhans cells to capture allergens from the skin surface; these cells then migrate to lymph nodes to present the allergen to T cells, promoting the development of regulatory T cells (Tregs) and inducing systemic desensitization.