Lacto series glycosphingolipid biosynthesis. Lactosylceramides (abbreviated as LacCer) are a class of glycosphingolipids connecting a ceramide lipid to a sugar group. The exact chemical formula and molecular weight in this class of lipids varies depending on the connected fatty-acid. Many of these structures are related to cancer development or antigens. Source: https://en.wikipedia.org/wiki/Lactosylceramide