Langerin/CD207 Protein, Human (HEK293, His)

CLC4K protein, a calcium-dependent lectin encoded by CD207, belongs to the C-type lectin domain family. CLC4K has mannose-binding specificity and is involved in antigen presentation to T cells. CLC4K is the major receptor for Candida, Saccharomyces, and Malassezia furfur on primary Langerhans cells. Langerhans cells are specialized antigen-presenting cells located within the epithelium of the epidermis and mucosa. Upon contact with Langerhans cells, pathogens are captured by the C-type lectin langerin and internalized into structurally unique vesicles called Birbeck granules (BGs). CLC4K induces the formation of Birbeck granules and protects against human immunodeficiency virus 1 (HIV-1) infection. Molecular mechanisms for membrane zipping exist during Birbeck granule biogenesis, and CLC4K is a potent regulator of membrane stacking and zipping. CLC4K binds to high-mannose structures present on the envelope glycoprotein and subsequently targets the virus to Birbeck particles, causing their rapid degradation. Langerhans cell histiocytosis (LCH) is a disorder characterized by clonal expansion of myeloid precursor cells that differentiate into CD1a1/CD207 cells within the lesion. Therefore, detection of clonal tumor proliferation with expression of CD1a, CD207 (Langerin), and S100 can help diagnose LCH.