%0 Journal Article
%T Cellular Kinetics of Perivascular MSC Precursors
%A William C. W. Chen
%A Tea Soon Park
%A Iain R. Murray
%A Ludovic Zimmerlin
%A Lorenza Lazzari
%A Johnny Huard
%A Bruno P¨Ļault
%J Stem Cells International
%D 2013
%I Hindawi Publishing Corporation
%R 10.1155/2013/983059
%X Mesenchymal stem/stromal cells (MSCs) and MSC-like multipotent stem/progenitor cells have been widely investigated for regenerative medicine and deemed promising in clinical applications. In order to further improve MSC-based stem cell therapeutics, it is important to understand the cellular kinetics and functional roles of MSCs in the dynamic regenerative processes. However, due to the heterogeneous nature of typical MSC cultures, their native identity and anatomical localization in the body have remained unclear, making it difficult to decipher the existence of distinct cell subsets within the MSC entity. Recent studies have shown that several blood-vessel-derived precursor cell populations, purified by flow cytometry from multiple human organs, give rise to bona fide MSCs, suggesting that the vasculature serves as a systemic reservoir of MSC-like stem/progenitor cells. Using individually purified MSC-like precursor cell subsets, we and other researchers have been able to investigate the differential phenotypes and regenerative capacities of these contributing cellular constituents in the MSC pool. In this review, we will discuss the identification and characterization of perivascular MSC precursors, including pericytes and adventitial cells, and focus on their cellular kinetics: cell adhesion, migration, engraftment, homing, and intercellular cross-talk during tissue repair and regeneration. 1. Introduction The availability of mesenchymal stem/stromal cells (MSCs) and MSC-like multipotent stem/progenitor cells marked a major milestone in stem cell therapies [1, 2]. For more than a decade, MSC has been a highly promising stem cell source and extensively investigated for its therapeutic potentials [3, 4]. Unlike embryonic stem cells (ESCs) or induced pluripotent stem cells (iPSCs), MSCs are inherently more relevant to clinical applications due to the lack of ethical and safety issues, despite lower developmental versatility [5]. MSCs and similar mesodermal stem/progenitor cells have been shown to repair and/or regenerate a wide variety of damaged/defective organs, including bone, cartilage, muscle, heart, and skin [6¨C10]. MSCs have also been reported to support hematopoiesis and suppress immune reaction after cell/organ transplantation [11¨C14]. Nevertheless, owing to the nature of MSC isolation by plastic adherence in tissue culture, the native identity and anatomical localization of MSCs have remained unclear for years [15]. Recently, several studies have indicated that MSCs represent a heterogeneous entity in culture, and a number of multipotent
%U http://www.hindawi.com/journals/sci/2013/983059/