– Latexin, also known as endogenous carboxypeptidase inhibitor, tissue carboxypeptidase inhibitor, TCI, ECI, and LXN, is a cytoplasm protein that belongs to the protease inhibitor I47 (latexin) family. It is highly expressed in the heart, prostate, ovary, kidney, pancreas, and colon. Latexin / LXN is the only known endogenous specific inhibitor of zinc-dependent metallocarboxypeptidases (MCPs) present in mammalians so far. Latexin is originally identified as a molecular marker for the regional specification of the neocortex in development in rats. The 222 amino acid latexin in the human shows different expression distribution with high levels in heart, prostate, ovary, kidney, pancreas, and colon, but only moderate or low levels in other tissues including the brain. Latexin is also expressed at high levels and is inducible in macrophages in concert with other protease inhibitors and potential protease targets, and thus is suggested to play a role in inflammation and innate immunity pathways. Despite the non-detectable sequence similarity with plant and parasite inhibitors, Latexin is related to a human putative tumor suppressor protein, TIG1. Also, Latexin is implicated in Alzheimer’s disease.