{"type": "root", "children": [{"type": "p", "children": [{"type": "t", "text": "\n CD207, also known as Langerin, is a C‐type lectin receptor primarily expressed on epidermal Langerhans cells and selected dendritic cell subsets. It mediates the capture and internalization of antigens—routing them into Birbeck granules for processing and subsequent presentation—which is vital for both pathogen clearance and the initiation of adaptive immune responses. For example, Langerin plays a protective role in HIV‐1 infection by internalizing virions into Birbeck granules where they are degraded rather than transmitted to T cells."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "1"}]}, {"type": "t", "text": " In addition, Langerin is expressed by subsets of dendritic cells that not only differ in origin and anatomical localization (with epidermal Langerhans cells distinguishable from blood‐derived and dermal Langerin⁺ DCs) but also contribute differentially to immune surveillance and antigen presentation in lymphoid tissues."}, {"type": "fg", "children": [{"type": "fg_fs", "start_ref": "2", "end_ref": "4"}]}, {"type": "t", "text": " Moreover, Langerin has been effectively exploited in vaccine strategies; targeting antigens to Langerin enhances cross‐presentation and stimulates robust CD4⁺ and CD8⁺ T cell responses."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "5"}]}, {"type": "t", "text": " Its function also extends to the presentation of nonpeptide antigens, as demonstrated in the context of Mycobacterium leprae infection where Langerin‐dependent processing appears to improve antigen‐specific T cell activation."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "7"}]}, {"type": "t", "text": " In genetic models, utilization of Langerin‐driven Cre recombinase has underscored an essential role for autocrine/paracrine transforming growth factor‐β signaling in maintaining Langerhans cell development and homeostasis."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "8"}]}, {"type": "t", "text": " Furthermore, aberrant accumulation of CD207⁺ cells is a hallmark of Langerhans cell histiocytosis"}, {"type": "fg", "children": [{"type": "fg_f", "ref": "9"}]}, {"type": "t", "text": ", and altered Langerin⁺ dendritic cell function appears to influence the pathogenesis of inflammatory skin disorders such as psoriasis."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "10"}]}, {"type": "t", "text": " Collectively, these studies highlight CD207/Langerin as a multifunctional receptor that not only orchestrates antigen uptake and presentation but also serves as a critical marker and therapeutic target in infection, immunization, and immune‐mediated skin diseases.\n "}]}, {"type": "rg", "children": [{"type": "r", "ref": 1, "children": [{"type": "t", "text": "Lot de Witte, Alexey Nabatov, Marjorie Pion, et al. 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