Uptake of Carbohydrate by Polyribosomes During the Immune Response to Ragweed Antigen

Abstract

The in vitro radioactive labeling of polyribosomes in slices of rabbit lymph glands, liver and other tissues engaged in glycoprotein synthesis was studied by sucrose density gradient analysis. Immunization which accelerates peptide synthesis in immunocompetent tissue also increased the incorporation of carbohydrate donated by uridine diphospho-N-acetylglucosamine (UDPAG). In lymph glands from immune animals, peaks of carbohydrate labeling in the gradients coincided with previously observed peaks of amino acid incorporation. In lymph glands and salivary glands, UDPAG was a more effective donor of carbohydrate than glucosamine. The possible role of Golgi apparatus was studied by using UDP-galactose as a sugar donor.