The splicing factor hnRNP C regulates expression of co-stimulatory molecules CD80 and CD40 in dendritic cells

• We discovered that splicing factor hnRNP C is involved in the maturation of dendritic cells.
• The expression of hnRNP C is upregulated during maturation of dendritic cells.
• HnRNP C regulates both CD80 and CD40 expression through NF-κB p65.

Maturation of dendritic cells is a key step during induction of adaptive immune responses. Multiple pathways and factors are involved in the regulation of dendritic cell maturation. Alternative splicing of pre-mRNA, which is regulated by splicing factors, plays an important role in many biological processes, including immune responses. To understand the roles of splicing factors in the maturation of dendritic cells, we analyzed the expression of the splicing factors hnRNP C and hnRNP A1 during maturation of the mouse dendritic cell line DC2.4 upon treatment with lipopolysaccharides (LPS). The expression of hnRNP C significantly increased after LPS stimulation. Knockdown or overexpression of hnRNP C respectively downregulated or upregulated the expression of nuclear factor-kappa B p65 as well as its downstream targets CD80 and CD40. Our results indicate that hnRNP C regulates the maturation of dendritic cells by affecting the expression of p65, CD80 and CD40.