CD318 (CUB domain containing protein 1) is a complement domains-containing transmembrane glycoprotein, which takes part in early hematopoiesis. It is expressed on CD34+CD133+ bone marrow cells, keratinocytes, and in human colorectal and breast cancers. It is being used as a marker of mesenchymal stem-like cells, neural progenitor cells, and also as an independent marker for the diagnosis of myeloid leukemias.Specificity : The mouse monoclonal antibody CUB1 recognizes an extracellular epitope of CD318, a type I transmembrane protein involved in early hematopoiesis.