Globotetraosylceramides are bioactive neutral glycosphingolipids. They are the major glycolipids in human erythrocytes. They act as receptors for the Shiga toxins Stx1, Stx2, and Stx2e, the cytotoxic protein pierisin-1, and parvovirus B19. Globotetraosylceramides increase the expression of proteins responsible for enamel deposition, including ameloblastin, amelogenin, and enamelin, in dental epithelial cells and activate the ERK and p38 MAPK signaling pathways. Levels of globotetraosylceramides are elevated in fibroblasts from patients with salt and pepper syndrome, a neurocutaneous condition characterized by intellectual disability and hyper- and hypo-pigmented skin. Globotetraosylceramides (porcine RBC) contains a mixture of globotetraosylceramides with variable fatty acyl chain lengths isolated from porcine red blood cells. [Matreya, LLC. Catalog No. 1068]