Establishment and characterization of immortalized sweat gland myoepithelial cells

Abstract

Sweat glands play an important role in thermoregulation via sweating, and protect human vitals. The reduction in sweating may increase the incidence of hyperthermia. Myoepithelial cells in sweat glands exhibit stemness characteristics and play a major role in sweat gland homeostasis and sweating processes. Previously, we successfully passaged primary myoepithelial cells in spheroid culture systems; however, they could not be maintained for long under in vitro conditions. No myoepithelial cell line has been established to date. In this study, we transduced two immortalizing genes into primary myoepithelial cells and developed a myoepithelial cell line. When compared with primary sweat gland cells, the immortalized myoepithelial cells (designated "iEM") continued to form spheroids after the 4th passage and expressed α-smooth muscle actin and other proteins that characterize myoepithelial cells. Furthermore, treatment with small compounds targeting the Wnt signaling pathways induced differentiation of iEM cells into luminal cells. Thus, we successfully developed an immortalized myoepithelial cell line having differentiation potential. As animal models are not useful for studying human sweat glands, our cell line will be helpful for studying the mechanisms underlying the pathophysiology of sweating disorders.

Morpho‐functional characterization of the submucosal glands at the nasopharyngeal end of the auditory tube in humans

“…Notably, a part of the sublingual gland-a major salivary gland-is uncapsulated, and lacks lobular organization and well-differentiated ductal hierarchy (Bradley & Guntinas-Lichius, 2011;Standring, 2021). Moreover, the myoepithelial cells are also present in tissue other than salivary, such as the submucosal glands of the trachea (Tata et al, 2018) and the secretory component of the sweat glands (Hayakawa et al, 2022) and excretory ducts of mammary glands (Gudjonsson et al, 2005). Furthermore, as an exception to the minor salivary glands, which are chiefly mucous, the von Ebner glands (present in the back of the tongue) are serous and secrete salivary amylase (Spielman et al, 1993;Standring, 2021).…”