Mesenchymal stem cell (MSC)-derived exosomes have been recognized as new candidates for cell-free treatment of various diseases. However, maintaining the retention and stability of exosomes over time in vivo after
transplantation is a major challenge in the clinical application of MSC-derived exosomes. Here, we investigated if human placenta-derived MSC-derived exosomes incorporated with
chitosan hydrogel could boost the retention and stability of exosomes and further enhance their
therapeutic effects. Our results demonstrated that
chitosan hydrogel notably increased the stability of
proteins and
microRNAs in exosomes, as well as augmented the retention of exosomes in vivo as confirmed by Gaussia
luciferase imaging. In addition, we assessed endothelium-protective and proangiogenesis abilities of
hydrogel-incorporated exosomes in vitro. Meanwhile, we evaluated the therapeutic function of
hydrogel-incorporated exosomes in a murine model of hindlimb
ischemia. Our data demonstrated that
chitosan hydrogel could enhance the retention and stability of exosomes and further augment the
therapeutic effects for hindlimb
ischemia as revealed by
firefly luciferase imaging of angiogenesis. The strategy used in this study may facilitate the development of easy and effective approaches for assessing and enhancing the
therapeutic effects of stem cell-derived exosomes.