Further tests suggested that epithelial cell progenitors helped by restoring the connection between cells called
myoepithelial contractile cells and the lacrimal gland's secretory cells, which produce tears.
The tissue, called the stroma, includes fat cells, or adipocytes, that provide padding; fibroblasts, which make the framework for tissue; pericytes in blood vessels, which are
contractile cells that help regulate blood pressure; as well as
myoepithelial cells comprising the outer layer of the ductal system through which milk flows.