Immunohistochemical Localization of Epithelial, Endothelial and Muscular Cell Differentiation Markers in Human Umbilical Cord

Introduction. Since time [1], our group studies through immunohistochemistry and RT-PCR analysis the expression of many genes and the localization of the corresponding proteins in the human umbilical cord [2], with the aim to create a map of the presence of the different molecules in the different territories of this organ. In this work we investigate the expression and localization of several cell differentiation markers in the different territories of the human umbilical cord. Materials and methods. The presence of E-Cadherin, CD31, CD68, AE1-AE3, Desmin, Actin ML, HHF35 and MIB-1 was studied through immunohistochemistry. Results. The expression of E-Cadherin (epithelial cell marker) has been identified in the amniotic epithelium of the human umbilical cord, while CD31 (endothelial cell marker) is present in the endothelia of all the three umbilical vessels. CD68 (macrophages marker) is expressed by some cells within the Wharton’s jelly and the vessels intima. AE1-AE3 (pankeratin) is present in the amniotic epithelium and in few cells of the Wharton’s jelly. Desmin and Actin ML (smooth muscle markers) are expressed in the vessels musculature and in the fibroblasts of the Wharton’s jelly while Actin 35 (HHF35) is present both in vessels musculature and in the intima. MIB-1 (cell proliferation index) expression was not identified in any of the territories of the umbilical cord. Conclusions. From this immunohistochemical data we realize that some of these cell differentiation markers (i.e. desmin and actin ML) are expressed not only in the territories where they perform their typical function (epithelia, endothelia, muscle) but also by other districts where their molecular role could contribute to address the differentiation of some cells towards other phenotypical conditions.