Expression of beta 1-6-branched N-linked oligosaccharides is associated with activation in human T4 and T8 cell populations.

Activation of human T lymphocytes by phorbol 12-myristate 13-acetate and leukoagglutinin from Phaseolus vulgaris (L-PHA) results in important changes in N-glycosylation. The most important event is the increase, in both T4 and T8 cells (especially the latter), of L-PHA+ structures characterized by beta 1-6-branching of complex-type oligosaccharides. Moreover, the existence of a CD4-mediated increase of these beta 1-6-branched structures on positively selected T4 cells, as compared with the negatively selected ones, suggests that the presence of these structures, not detectable on T8 resting cells, could be related to stimulation events triggered by both selection methods. This beta 1-6-branching on N-glycans, strongly associated with a metastatic phenotype in human and rodent tumors, is exhibited by numerous glycoproteins on stimulated cells, as shown by blot analysis.