Peanut agglutinin high phenotype of activated CD8+ T cells results from de novo synthesis of CD45 glycans.
Following activation in the periphery, murine CD8+ T cells exhibit a characteristic increased binding of peanut agglutinin (PNA), reflecting an increased expression of hyposialylated O-linked glycans (Galbeta1-3GalNAcalpha-O-Thr/Ser) on the cell surface. In this report, we show that the majority of the PNA receptors expressed on activated CD8+ T cells are carried by CD45. Other glycoproteins (e.g. CD8) and the glycolipid asialo-GM1 also carry PNA receptors, although to a much lesser extent. Analysis of enzymes involved in the sialylation/de-sialylation pathways showed that generation of PNA receptors in activated CD8+ T cells is not due to up-regulation of endogenous sialidases. Instead, our results indicate that the PNA(high) phenotype results from de novo synthesis of CD45 carrying reduced sialylated core 1 O-glycans.
Amado
Margarida
M
Departments of Molecular Biology and Molecular and Experimental Medicine, The Scripps Research Institute, 10550 Torrey Pines Road, La Jolla, CA 92037, USA.
Yan
Qi
Q
Comelli
Elena M
EM
Collins
Brian E
BE
Paulson
James C
JC
D000818:Animals; D001710:Biotin / Q000737:chemistry / Q000378:metabolism; D015153:Blotting, Western; D018414:CD8-Positive T-Lymphocytes / Q000378:metabolism*; D019556:COS Cells; D002462:Cell Membrane / Q000378:metabolism; D002855:Chromatography, Thin Layer; D005434:Flow Cytometry; D006023:Glycoproteins / Q000737:chemistry; D037102:Lectins / Q000378:metabolism; D017493:Leukocyte Common Antigens / Q000096:biosynthesis* / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D008954:Models, Biological; D008956:Models, Chemical; D009439:Neuraminidase / Q000378:metabolism; D019887:Peanut Agglutinin / Q000378:metabolism*; D010641:Phenotype; D011134:Polysaccharides / Q000737:chemistry / Q000378:metabolism*; D011233:Precipitin Tests; D011485:Protein Binding; D012313:RNA / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012799:Sialyltransferases / Q000737:chemistry; D013154:Spleen / Q000166:cytology; D013601:T-Lymphocytes / Q000378:metabolism; D000094663:beta-Galactoside alpha-2,3-Sialyltransferase
D006023:Glycoproteins; D037102:Lectins; D019887:Peanut Agglutinin; D011134:Polysaccharides; D012313:RNA; D001710:Biotin; D012799:Sialyltransferases; D017493:Leukocyte Common Antigens; D009439:Neuraminidase; D000094663:beta-Galactoside alpha-2,3-Sialyltransferase