 This study investigates the possibility of using exosomes secreted from pre-differentiated stem cells to replace stem cells in order to facilitate bone regeneration. Exosomes were isolated from stem cells that had been pre-differentiated for either 10 or 15 days, and then loaded onto 3D printed titanium alloy scaffolds. After 12 weeks, it was observed that the exosome loaded scaffold was able to regenerate bone tissue just as effectively as the scaffold without exosomes. This indicates that the exosomes may be responsible for the successful regeneration of bone tissue. Furthermore, the researchers found that the exosomes contained specific MIRNAs which could potentially explain how they were able to stimulate the PI3K slash AKT and MAPK signaling pathways, leading to the activation of osteoblasts and ultimately the regeneration of bone tissue. This article was authored by Mingming Zhai, Yi Zhu, Mingjing Yang, and others.