15 Jul 2015 Blackmores Institute Vitamin A directs immune cells to the intestines study 15 Jul 2015 Share Share on LinkedIn Share on Facebook Share on Twitter Share on Google+ Share on Pinterest News A key set of immune cells that protect the body from infection would be lost without directions provided by vitamin A, according to a recent study. A team of researchers from Purdue University, Indiana, found retinoic acid, a metabolite that comes from digested vitamin A, is necessary for two of the three types of innate immune cells that reside in the intestine to find their proper place. × To continue reading this article, please Log In or Sign Up for access.