The Role of Interplay of Mesenchymal Stromal Cells and Macrophages in Physiological and Reparative Tissue Remodeling

Monocytes and their progeny, macrophages (MPhs), play the leading role in the innate immunity and populate different tissues maintaining homeostasis. In addition, these cells are involved in the response to injury when they accumulate in significant numbers at inflammatory sites. As well as macrophages, multipotent mesenchymal stromal cells (MSCs) are a critical component of both physiological and emerging regenerative microenvironment. Reciprocal effects of resident stromal and recruited blood-borne cells orchestrate cellular reactions in the tissues. Hypoxia, a significant reduction in the O2 concentration, is a characteristic feature of the compromised microenvironment. The present review analyzes the current concepts of the role of MSC interaction with MPhs in physiological and reparative tissue remodeling, modulation of MSC and MPh functions under acute hypoxic stress and discusses how oxygen deprivation can affect the outcome of MSC–MPh interplay.