SiaNAl can be efficiently incorporated in glycoproteins of human mesenchymal stromal cells by metabolic glycoengineering

Metabolic glycoengineering involves the stimulation of
cells with
functionalized monosaccharides. Glucosamine, galactosamine, and mannosamine
derivatives are commercially available, but their application may
lead to undirected (i.e., chemical) incorporation into proteins. However,
sialic acids are attached to the ends of complex sugar chains of glycoproteins,
which might be beneficial for cell surface modification via click
chemistry. Thus, we studied the incorporation of chemically synthesized
unnatural alkyne modified sialic acid (SiaNAl) into glycoproteins
of human telomerase-immortalized mesenchymal stromal cells (hMSC-TERT)
and we show that SiaNAl can be efficiently incorporated in glycoproteins
involved in signal transduction and cell junction.