Vitamin D regulates LAMP3 expression in monocyte derived dendritic cells.

The family of lysosome-associated membrane proteins (LAMPs) encompassing LAMP1, LAMP2 and DC-LAMP (LAMP3) are the major constituents of the glycoconjugates coat present on the inside of the lysosomal membrane. LAMP3 is highly expressed only in certain cell types and during the differentiation stages. Its expression is linked the maturation of dendritic cells, inflammation, poor prognosis of certain tumors, and the locus where it is encoded was identified as a risk factor for Parkinson's disease (PD). Here, we investigated the capacity of Vitamin D to modulate the expression of LAMP3 during the dendritic cells differentiation and maturation. Our results demonstrated that the Vitamin D reduce the LAMP3 mRNA/protein expression during the dendritic cells differentiation and maturation, via NFκB pathways. Furthermore, we demonstrated that the Vitamin D was able to modulate the expression of LAMP3 likewise to in vitro tolerogenic dendritic cells. In summary, these data showed that the decrease of LAMP3 expression by Vitamin Dcould enhance the tolerogenic characteristic of dendritic cells.