REGULATION OF LYMPHOCYTE AND MONOCYTE IMMUNE FUNCTIONS BY VITAMIN A COMPOUNDS

点击翻译按钮获取中文摘要

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The purpose is to test whether human blood monocytes and lymphocytes display characteristics of antigen-presenting cells (APCs) after exposure in culture to vitamin A or related retinoids. Antigen presentation is critical for immune responses, including CD4 and CD8 T cell activation. The hypothesis is based on work we have conducted with a transformed human monocytic cell line, THP-1, which has shown that exposure to physiological concentrations of retinoic acid, an active metabolite of vitamin A, induces the expression of molecules involved in antigen presentation: CD1d, an MHC-I-like molecule (implicated in lipid antigen presentation), MHC-II molecules (peptide antigen presentation), and DC-SIGN (CD209, carbohydrate antigen presentation). The data suggest that retinoic acid induces THP-1 monocytic cells to become APCs. To show that this effect of RA is not limited to transformed cells, it is important to demonstrate that normal human monocytes can be similarly regulated.