C-type lectin domain family 4 member C (BDCA-2) (BDCA-2)

C-type lectin domain family 4 member C, commonly known as Blood Dendritic Cell Antigen 2 (BDCA-2), is a type II transmembrane receptor exclusively expressed on human plasmacytoid dendritic cells (pDCs) [4, 12]. It serves as a critical negative regulator of the innate immune response, specifically inhibiting the production of type I interferons (IFN-I) and other pro-inflammatory cytokines when triggered by Toll-like receptors 7 and 9 [1, 4]. In autoimmune conditions such as systemic lupus erythematosus (SLE) and cutaneous lupus erythematosus (CLE), pDCs become chronically activated, leading to an overproduction of IFN-I that drives tissue inflammation and disease progression [2, 16]. Therapeutic strategies targeting BDCA-2, such as the monoclonal antibody litifilimab, utilize the receptor's endocytic properties to induce its internalization and subsequent degradation [3, 6]. This process effectively dampens the pDC-mediated inflammatory cascade, offering a targeted approach to treating lupus while potentially minimizing the broad immunosuppression associated with conventional therapies [14, 16].

Other names

Blood dendritic cell antigen 2CD303CLEC4CDLECDendritic lectin

Binding to BDCA-2 induces rapid receptor internalization and degradation, which inhibits Toll-like receptor (TLR)-induced production of type I interferons and other pro-inflammatory cytokines by plasmacytoid dendritic cells [3, 6].