Martje Erkelens

The vitamin A derived metabolite retinoic acid (RA) is important for proper embryonic development, vision and immune regulation. Vitamin A is metabolized via retinal into RA by the RALDH enzymes, of which three isoforms exist: RALDH1, RALDH2 and RALDH3. Intestinal epithelial cells express RALDH1 and can metabolize dietary derived vitamin A into RA, which is involved in the induction of RALDH2 in dendritic cells providing them with their tolerogenic potential. We surmise that intestinal epithelial cells may have a role in regulating tolerogenic immune functions and in the development of autoimmune diseases. Therefore, we question what factors can influence RALDH expression in the gut. To investigate this, we are developing chemical probes which will enable us to study RALDH activity in both a qualitative as well as a quantitative manner