Mycophenolic acid does not inhibit protein glycosylation in T lymphocytes

Mycophenolic acid inhibits guanosine nucleotide synthesis and has been shown to be a potent inhibitor of lymphocyte proliferation as well as being effective at decreasing the incidence of graft rejection. Guanosine nucleosides are essential for protein glycosylation and many cell surface proteins including adhesion molecules, which are important for graft infiltration and rejection, are glycoproteins. There have been conflicting reports concerning the ability of MPA to interfere with glycosylation in lymphoid cells. Therefore, the purpose of this study was to investigate the effects of MPA on cell surface protein glycosylation in lymphoid cells.

Cells were cultured in the presence of increasing concentrations of MPA for different lengths of time and stained with fluorescent-labelled lectins specific for either mannose or fucose residues on glycoproteins. Analysis was then performed by flow cytometry.

MPA treatment had no effect on the binding of either fucose or mannose-specific lectins to Con A stimulated human PBLs and rat lymph node lymphocytes or to a CEMC7a T cell line.

The results show that, contrary to previous reports, MPA does not affect cell surface glycosylation in T cells using T cells from different sources of both human and non-human origin.