The CLEC4C gene, also known as BDCA-2 or CD303, encodes a type II transmembrane C-type lectin receptor predominantly expressed by plasmacytoid dendritic cells (pDCs) ^[1]. This receptor plays a critical role in pDC biology and serves as a key marker for this cell type ^[2]. The CLEC4C protein, featuring a carbohydrate recognition domain, is implicated in the capture and subsequent processing of antigens, potentially through the recognition of specific glycans and immunoglobulin G ^[1]. Functionally, CLEC4C acts as a signaling receptor within pDCs, and its engagement can negatively regulate the production of type I interferons, thereby modulating immune responses ^[2]. Notably, dysregulation of CLEC4C expression and pDC function has been associated with the pathogenesis of autoimmune disorders, including systemic lupus erythematosus (SLE), as well as in the context of certain hematological malignancies ^[3]. Litifilimab is a monoclonal antibody that targets CLEC4C and is under investigation for the treatment of SLE and other interferonopathies ^[4]. CLEC4C is a human gene, while Clec4b1 is its orthologous gene in mice. The B6-hCLEC4C mouse is a humanized model constructed by replacing the mouse Clec4b1 endogenous extracellular domain with the human CLEC4C extracellular domain. This model can be used to study the pathological mechanisms and therapeutic methods of autoimmune disorders and hematological malignancies, as well as the screening and development of CLEC4C-targeted drugs, and preclinical efficacy and safety evaluations.

The CLEC4C gene, also known as BDCA-2 or CD303, encodes a type II transmembrane C-type lectin receptor predominantly expressed by plasmacytoid dendritic cells (pDCs) ^[1]. This receptor plays a critical role in pDC biology and serves as a key marker for this cell type ^[2]. The CLEC4C protein, featuring a carbohydrate recognition domain, is implicated in the capture and subsequent processing of antigens, potentially through the recognition of specific glycans and immunoglobulin G ^[1]. Functionally, CLEC4C acts as a signaling receptor within pDCs, and its engagement can negatively regulate the production of type I interferons, thereby modulating immune responses ^[2]. Notably, dysregulation of CLEC4C expression and pDC function has been associated with the pathogenesis of autoimmune disorders, including systemic lupus erythematosus (SLE), as well as in the context of certain hematological malignancies ^[3]. Litifilimab is a monoclonal antibody that targets CLEC4C and is under investigation for the treatment of SLE and other interferonopathies ^[4]. B6-H11-hCLEC4C mice are humanized models generated by gene editing technology, in which the human CLEC4C genomic DNA was inserted at the H11 safe harbor. This modification does not affect the expression of the mouse homologous gene Clec4b1. This model can be used to study the pathological mechanisms and therapeutic methods of autoimmune disorders and hematological malignancies, as well as the screening and development of CLEC4C-targeted drugs, and preclinical efficacy and safety evaluations.