TYMP (Thymidine Phosphorylase, TP) is an angiogenic factor that promotes angiogenesis in vivo and stimulates the in vitro growth of a variety of endothelial cells. It has a highly restricted target cell specificity, acting only on endothelial cells. Mutations in TYMP are associated with mitochondrial neurogastrointestinal encephalomyopathy (MNGIE). In immunohistochemistry of normal tissue, TYMP has nuclear and cytoplasmic positivity in populations of immune cells and is also present in the brain, lung, kidney, prostate, skin, endometrium and a few other tissues throughout the body. References: The UniProt Consortium. Nucleic Acids Res. 47: D506-515 (2019); Nucleic Acids Res. 2016 Jan 4;44(D1):D733-45, PMID:26553804;