Expression and localisation of thymosin beta-4 in the developing human early fetal heart.

ABSTRACT: BACKGROUND:The objective of this study was to investigate the expression and localisation of thymosin ?4 (T?4) in the developing human heart. T?4 is a cardioprotective protein which may have therapeutic potential. While T?4 is an endogenously produced protein with known importance during development, its role within the developing human heart is not fully understood. Elucidating the localisation of T?4 within the developing heart will help in understanding its role during cardiac development and is crucial for understanding its potential for cardioprotection and repair in the adult heart. METHODS:Expression of T?4 mRNA in the early fetal human heart was assessed by PCR using both ventricular and atrial tissue. Fluorescence immunohistochemistry was used to assess the localisation of T?4 in sections of early fetal human heart. Co-staining with CD31, an endothelial cell marker, and with myosin heavy chain, a cardiomyocyte marker, was used to determine whether T?4 is localised to these cell types within the early fetal human heart. RESULTS:T?4 mRNA was found to be expressed in both the atria and the ventricles of the early fetal human heart. T?4 protein was found to be primarily localised to CD31-expressing endothelial cells and the endocardium as well as being present in the epicardium. T?4-associated fluorescence was greater in the compact layer of the myocardial wall and the interventricular septum than in the trabecular layer of the myocardium. CONCLUSIONS:The data presented illustrates expression of T?4 in the developing human heart and demonstrates for the first time that T?4 in the human heart is primarily localised to endothelial cells of the cardiac microvasculature and coronary vessels as-well as to the endothelial-like cells of the endocardium and to the epicardium.

SUBMITTER: Saunders V 

PROVIDER: S-EPMC6226193 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature