Activation of murine CD4+ and CD8+ T lymphocytes leads to dramatic remodeling of N-linked glycans.
Differentiation and activation of lymphocytes are documented to result in changes in glycosylation associated with biologically important consequences. In this report, we have systematically examined global changes in N-linked glycosylation following activation of murine CD4 T cells, CD8 T cells, and B cells by MALDI-TOF mass spectrometry profiling, and investigated the molecular basis for those changes by assessing alterations in the expression of glycan transferase genes. Surprisingly, the major change observed in activated CD4 and CD8 T cells was a dramatic reduction of sialylated biantennary N-glycans carrying the terminal NeuGcalpha2-6Gal sequence, and a corresponding increase in glycans carrying the Galalpha1-3Gal sequence. This change was accounted for by a decrease in the expression of the sialyltransferase ST6Gal I, and an increase in the expression of the galactosyltransferase, alpha1-3GalT. Conversely, in B cells no change in terminal sialylation of N-linked glycans was evident, and the expression of the same two glycosyltransferases was increased and decreased, respectively. The results have implications for differential recognition of activated and unactivated T cells by dendritic cells and B cells expressing glycan-binding proteins that recognize terminal sequences of N-linked glycans.
Comelli
Elena M
EM
Departments of Molecular Biology and Molecular and Experimental Medicine, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
Sutton-Smith
Mark
M
Yan
Qi
Q
Amado
Margarida
M
Panico
Maria
M
Gilmartin
Tim
T
Whisenant
Thomas
T
Lanigan
Caroline M
CM
Head
Steven R
SR
Goldberg
David
D
Morris
Howard R
HR
Dell
Anne
A
Paulson
James C
JC
D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D002478:Cells, Cultured; D020869:Gene Expression Profiling; D008213:Lymphocyte Activation / Q000276:immunology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008969:Molecular Sequence Data; D011134:Polysaccharides / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
D011134:Polysaccharides