Ganglioside GT1b is a trisialoganglioside that is characterized by having two sialic residues linked to the inner galactose unit. It binds to the neurotoxins botulinum toxin serotype A (BTxA), BTxA heavy chain, and tetanus toxin with IC50 values of 11, 0.74, and 7.2 ?M, respectively.{37775} Ganglioside GT1b-containing liposomes bind to the major coat protein VP1 from Merkel cell polyomavirus (MCPyV), which has been identified in Merkel cell carcinomas, identifying ganglioside GT1b as a putative MCPyV receptor.{25480} Ganglioside GT1b decreases spontaneous production of IL-6, IL-10, IgG, IgM, and IgA in human peripheral blood mononuclear cells (PBMCs) by 31.4, 30.5, 60, 59.5, and 58%, respectively, when used at a concentration of 10 ?M.{25482} This product contains ganglioside GT1b molecular species with primarily C18:0 fatty acyl chain lengths. As this product is derived from a natural source, there may be variations in the sphingoid backbone. [Matreya, LLC. Catalog Number. 1548]