Testing the paracrine properties of human mesenchymal stem cells using conditioned medium

Mesenchymal stem cells (MSC) produce and secrete a great variety of cytokines and chemokines that play beneficial paracrine actions when MSC are used for tissue repair. The conditioned medium (CM) derived from MSC can be used both in vitro and in vivo to test specific paracrine effects or to screen putative paracrine/autocrine mediators by proteomics.In this chapter, we describe a straightforward method to prepare MSC-derived CM. Furthermore, we summarize some in vitro assays useful for testing the cytoprotective, angiogenic, and regenerative activity of CM. These assays are very helpful when studying the role of MSC in cardiac repair and regeneration.