Fig. 2.

Schematic illustration of the roles of CCL2 and CXCL1 released from lipid loading cells in enhancing MSC chemotaxis. CCL2 and CXCL1 released by lipid loading cells into the medium bind to their corresponding receptors CCR2 and CXCR2 on MSCs. The GTPases Rac1 and Cdc42 become activated and then p38 is phosphorylated via Rac1, finally leading to increased migration, which induces expression of cytoskeleton related proteins paxillin, vinculin and phosphorylated FAK, which may also activate the Rac1 or Cdc42 signalling pathways