Recruitment of bone marrow-derived valve interstitial cells is a normal homeostatic process

► Bone marrow-derived valve interstitial cells are CD45+. ► CD45+ interstitial cells have distinct localization in the valves. ► Most of the valve CD45+ cells are progenitor cells. ► A subpopulation of valve CD45+ cells exhibit fibroblast-like properties. ► Recruitment of CD45+ cell to the valve is not a response to lethal irradiation.