Huc-MSC-derived exosomes modified with the targeting peptide of aHSCs for liver fibrosis therapy

Abstract

Background Effective therapeutics to stop or reverse liver fibrosis have not emerged, because these potential agents cannot specifically target activated hepatic stellate cells (aHSCs) or are frequently toxic to parenchymal cells. Human umbilical cord mesenchymal stem cell (Huc-MSC)-derived exosomes show promise in nanomedicine for the treatment of liver fibrosis. However, systemic injection showed that unmodified exosomes were mainly taken up by the mononuclear phagocyte system. The discovery of ligands that selectively bind to a specific target plays a crucial role in clinically relevant diagnostics and therapeutics. Herein, we aimed to identify the targeting peptide of aHSCs by screening a phage-displayed peptide library, and modify Huc-MSC-derived exosomes with the targeting peptide. Results In this study, we screened a phage-displayed peptide library by biopanning for peptides preferentially bound to HSC-T6 cells. The identified peptide, HSTP1, also exhibited better targeting ability to aHSCs in pathological sections of fibrotic liver tissues. Then, HSTP1 was fused with exosomal enriched membrane protein (Lamp2b) and was displayed on the surface of exosomes through genetic engineering technology. The engineered exosomes (HSTP1-Exos) could be more efficiently internalized by HSC-T6 cells and outperformed both unmodified exosomes (Blank-Exos) and Lamp2b protein overexpressed exosomes (Lamp2b + Exos) in enhancing the ability of exosomes to promote HSC-T6 reversion to a quiescent phenotype. In vivo results showed HSTP1-Exos could specifically target to the aHSC region after intravenous administration, as demonstrated by coimmunofluorescence with the typical aHSCs marker α-SMA, and enhance the therapeutic effect on liver fibrosis. Conclusion These results suggest that HSTP1 is a reliable targeting peptide that can specifically bind to aHSCs and that HSTP1-modified exosomes realize the precise treatment for aHSCs in complex liver tissue. We provide a novel strategy for clinical liver fibrosis therapy. Graphical Abstract

Therapeutic potential of exosome‐based personalized delivery platform in chronic inflammatory diseases

“…This strategy allows the expression of peptides and proteins of interest on the surface of exosomes and endows them with diverse functions [53] . The fusion of targeted peptide HSTP1 with membrane protein Lamp2b effectively promoted the uptake of exosomes by HSC-T6 cells [54] . However, conventional genetic engineering strategy has the disadvantages of low efficiency and low membrane protein expression.…”

Liver fibrosis: pathological features, clinical treatment and application of therapeutic nanoagents

“…7(C)). 156 In addition, exosomes, as promising natural nanocarriers capable of efficiently entering cells with different biological barriers, have attracted a lot of attention in terms of antifibrosis drug delivery or siRNAs therapy. Heikal et al developed Fig.…”

“…(C) Engineered exosomes targeted aHSCs by peptide HSTP1 modification. 156 Copyright 2022, adapted with permission from the author(s).…”

Exosomes in liver fibrosis: The role of modulating hepatic stellate cells and immune cells, and prospects for clinical applications

“…However, engineered exosomes offer a potential solution to this issue. For instance, exosomes modified with targeted peptides of aHSC can increase the efficiency of targeted hepatic stellate cell delivery and improve efficacy in treating LF ( 86 ). The use of native exosomes as LF therapeutic agents has other drawbacks, including a lack of long-term studies to assess safety and efficacy, a lack of comprehensive exploration of therapeutic mechanisms, and the potential for prohibitive costs.…”