Extrahepatic and Intrahepatic Human Portal Interstitial Cajal Cells

Abstract

Portal interstitial cells of Cajal (PICCs), acting as vascular pacemakers, were previously only identified in nonhumans. Moreover, there is no evidence available about the presence of such cells within the liver. The objective of the study is to evaluate whether or not PICCs are identifiable in humans and, if they are, whether or not they are following the scaffold of portal vein (PV) branches within the liver. We obtained extrahepatic PVs and liver samples from six adult human cadavers, negative for liver disease, in accordance with ethical rules. They were stained with hematoxylin-eosin (HE) and Giemsa, and then we performed immunohistochemistry on formalin-fixed paraffin-embedded specimens for CD117/c-kit, a marker of the Cajal's cells. Immune labeling was also performed for S-100 protein, desmin, glial fibrillary acidic protein (GFAP), neurofilaments, a-smooth muscle actin (a-SMA), and CD34. c-kit-Positive PICCs were identified within the extrahepatic PV, in portal spaces, and septa. On adjacent sections, these PICCs were negative for all the other antibodies used. In conclusion, our study confirms the presence of extrahepatic PICCs on humans, which may act as a possible intrinsic pacemaker in the human PV. However, the intrahepatic PICCs, which were evidenced here for the first time, are in need for further experimental studies to evaluate their functional role. A promising further direction of the study is the PICCs role in the idiopathic portal hypertension. Anat Rec, 294:1382Rec, 294: -1392Rec, 294: , 2011. V V C 2011 Wiley-Liss, Inc.

Telocytes: ultrastructural, immunohistochemical and electrophysiological characteristics in human myometrium

“…2011 a ), blood vessels (Cantarero et al . 2011, Rusu et al . 2011), pancreas (Nicolescu & Popescu 2012), parotid gland (El-Bassouny 2012, Nicolescu et al .…”

Telocytes in neuromuscular spindles

“…A peculiar type of interstitial (stromal) cells named telocytes (TCs; cell bearing long prolongations/stromal cells with telopodes – Tps ‐) has been described and adopted by several laboratories [for review see and for details visit http://www.telocytes.com]. Formerly called interstitial‐like (Cajal‐like) cells, TCs have been observed in several tissues and organs, including skin, respiratory tract, cardiovascular system, gastrointestinal tract, liver, gallbladder, pancreas, parotid gland, female reproductive system, breast, placenta, urinary tract and meninges and choroid plexus .…”

Tracheal telocytes

“…Characteristically, Tp have thin segments (podomers) and dilations (podoms) [2–7] which house mitochondria, endoplasmic reticulum and caveolae [8, 9]. TC present in mouse trachea were reported very recently by Zheng et al [8].…”