Figure 1.

Mesenchymal stem cell self-renewal and cytodifferentiation. Extracellular signaling factors, including growth factors and cytokines, demonstrated to promote and/or maintain mesenchymal stem cell (MSC) self-renewal, in vitro. Gene markers characteristic of MSC self-renewal include oct-4, sox-2, and rex-1. LIF, leukemia inhibitory factor; EGF, epidermal growth factor; HGF, hepatocyte growth factor; PDGF, platelet-derived growth factor; FGF, fibroblast growth factor; CFU-F, colony forming unit-fibroblast; c, chondroblast; o, osteoblast; a, adipoblast; m, myoblast; cm, cardio-myoblast; t, tenoblast.