The Role of Galectin-1 on B cell Activation

While intracellular regulatory mechanisms that govern B cell activation are well understood, significant gaps in our knowledge remain regarding extracellular mechanisms that may regulate B cell signalling and activation. Galectins, which are glycan-binding proteins, are known to form glycan-galectin lattices which can regulate protein-protein interactions on the cell surface. Thus, we examined a role for Galectin-1 (Gal-1) as an extracellular modulator of B cell activation. We found that Gal-1 is important in mediating isotype switching to IgG2a and IgA antibodies during antigenic challenge demonstrating a crucial role for the protein in regulating the humoral response. We show that the ligand for Gal-1 is present on the surface of naïve B cells and that B cells secrete Gal-1 upon activation. Finally, we found that recombinant Gal-1 can enhance cell-cell interaction between macrophages and B cells thus demonstrating an important role for the protein in promoting cell-cell interaction between B cells and antigen presenting cells.M.Sc.2017-11-30 00:00:0