Multipotent mesenchymal stromal cell-based therapies: Regeneration versus repair

Abstract

Multipotent mesenchymal stromal cells (MSCs) have attracted much attention for their multipotency, low immunogenicity, immunomodulatory properties, ability to home to sites of injury, and also for their ease in procurement and expansion abilities in culture. Altogether, these properties have pushed MSCs on the fast-track as potential candidates for cell-based therapy approaches. In the attempt to understand the mechanisms underlying the therapeutic effects observed in preclinical animal models and clinical studies after MSC transplantation, the question arises as to whether these are based on a true MSC regenerative ability, or if they are a result of a complex cross-talk between MSCs, the bioactive factors they release and the microenvironment which they occupy. This chapter will thoroughly discuss evidence of both notions in a variety of pathological conditions in preclinical models and clinical studies, and highlight the obstacles encountered, lessons learned, and warrant future investigations to better understand the therapeutic effects of MSCs and their potential additional clinical properties.