Cellular distribution in rat liver of intravenously administered polyacryl starch and chondroitin sulfate microparticles

The interaction of polyacryl starch and chondroitin sulfate (CS) microparticles with rat liver cells was studied in vivo and in cell cultures. Kupffer cells (KC) in culture avidly engulfed both starch and CS particles. Cultured liver endothelial cells (LEC) bound CS, and to a lesser degree starch particles. Parenchymal cells (PC) in culture did not bind any of the particles. I.v. injection of either type of particles labelled with fluorescein isothiocyanate, and subsequent isolation of the liver cells showed uptake only in KC. After i.v. administration of 14C-labelled particles, radioactivity was accumulated mainly in KC. Thus, polysaccharide microparticles in the μm range may be suitable for targeting drugs to KC.