C-Kit is a member of a subfamily of receptor tyrosine kinases that includes PDGF, CSF-1, and FLT3/flk-2 receptors. Studies have shown that c-Kit plays a critical role in the activation and growth of a number of cell types including hematopoietic stem cells, mast cells, melanocytes, and germ cells. Mutations in c-Kit have been associated with gastrointestinal stromal tumors, testicular seminoma, mast cell disease, melanoma, and acute myeloid leukemia. Antibodies to c-Kit are widely used in immunohistochemistry to distinguish between different types of tumors in histological tissue sections. MSD’s Phospho/Total c-Kit uses a traditional immuno-sandwich format to accurately measure total and phosphorylated levels of human c-Kit in cellular lysates and whole cells, and is compatible with many cell types. This kit provides the assay-specific components for the quantitative determination of phosphorylated c-Kit in human serum and plasma samples.