PrP^c and reggies/flotillins are contained in and released via lipid-rich vesicles in Jurkat T cells

Abstract

A new model of caveolin association with lipid body cores has recently been proposed which may be relevant to a number of cellular processes, e.g. lipid body generation. Here we show that PrP^c and reggie-1 and reggie-2 also occur in the cores of Nile Red/Bodipy-stained (neutral lipid-containing) vesicular structures and, in immunoblots, in the lipid-enriched fraction after density gradient centrifugation. These lipid-rich vesicles increase in number following cell feeding with oleic acid, differ from early endosome antigen 1- and Lamp-2-positive endosomes/lysosomes, exhibit an opaque content and lack surrounding actin staining. Our results suggest that the content of these vesicles, together with reggie-1 and -2 and PrP^c, is expelled.