Hydrogel Loaded with VEGF/TFEB‐Engineered Extracellular Vesicles for Rescuing Critical Limb Ischemia by a Dual‐Pathway Activation Strategy

Abstract

Critical limb ischemia (CLI) is the most severe clinical manifestation of peripheral arterial disease, which causes many amputations and deaths. Conventional treatment strategies for CLI (e.g., stent implantation and vascular surgery) bring surgical risk, which are not suitable for each patient. Extracellular vesicles (EVs) can be a potential solution for CLI. Herein, vascular endothelial growth factor (VEGF; i.e., a crucial molecule related to angiogenesis) and transcription factor EB (TFEB; i.e., a pivotal regulator of autophagy) are chosen as the target gene to improve the bioactivity of EVs derived from endothelial cells. The VEGF/TFEB-engineered EVs (Engineered-EVs) are fabricated by genetically engineering the parent cells, and their versatile functions are confirmed using three cell models (human umbilical vein endothelial cells, myoblast, and monocytes). Injectable thermal-responsive hydrogel are then combined with Engineered-EVs to combat CLI. These results reveal that the hydrogel can enhance the stability of Engineered-EVs in vivo and release EVs at different temperatures. Moreover, the results of animal studies indicate that Engineered-EV/Hydrogel can significantly improve neovascularization, attenuate muscle injury, and recover limb function after CLI. Finally, mechanistic studies shed light on the therapeutic effect of Engineered-EV/Hydrogel due to the activated VEGF/VEGFR pathway and autophagy-lysosomal pathway.

Designer Extracellular Vesicles Modulate Pro‐Neuronal Cell Responses and Improve Intracranial Retention

“…This type of molecular makeup for cargo packed in EVs (i.e., DNA, RNA, and proteins) has been previously reported in the literature. [56][57][58] Experiments with the exosome release inhibitor GW4869 provided additional insight into the cargo loading of these pro-neurogenic designer EVs. GW4869 led to a significant decrease in the number of EVs released into the supernatant post-transfection, and in this case although the overall amount of ABM plasmid packed in the EVs did not change in response to the inhibitor, a tendency to increase loading with ABM transcripts was observed (Figure S5C-F, Supporting Information).…”

Tissue engineering modalities in skeletal muscles: focus on angiogenesis and immunomodulation properties

“…Elastin is an essential constituent of ECM and is promised biomaterial in skeletal muscle and vessel reconstitution because of its appropriate mechanical strength and elasticity [ 273 ]. Elastin plays an important role in the stimulation of cell signaling cascades associated with proliferation and angiogenesis [ 274 ].…”

The Role of Extracellular Vesicles in Osteoporosis: A Scoping Review

“…Engineered EVs refer to the artificially modified EVs, with great potential in the treatment of various diseases, including tumors, spinal cord injury, inflammation, cardiovascular diseases, etc. At present, there are two methods to achieve this: one is to modify the cells, co-incubate or transfect the genes or drugs so that the genes or drugs can enter into the cells, and then collect the EVs of the cells; and another is to directly add RNAs or drugs to the EVs to make the EVs have therapeutic effects [ 86 , 87 , 88 , 89 , 90 , 91 , 92 , 93 , 94 , 95 , 96 ].…”