Author + information
- Liang Mao,
- Xue Li,
- Li Huang,
- Xuehui Fan,
- Hua Yu,
- Xiaorong Zeng and
- Xitong Dang
The discovery of exosome, a nanosized natural carrier of signal molecules facilitating cell-cell communication, has reignited the interest in vector design for gene therapy. Exosome overcomes many drawbacks associated with traditional vectors such as low transfection efficiency, risk of viral vector integration, inflammation, high immunogenicity, and inability to penetrate biological barriers among others. In addition, exosome membrane resulted from two successive invaginations of plasma membrane shares high similarity with plasma membrane including the orientation of transmembrane proteins. Hypothesis: Transmembrane proteins can be engineered to display a homing peptide on the surface of exosomes, which will bind and then unload their cargos to the recipient cells bearing cognate known/unknown receptors, therefore realizing targeted cargo delivery.
A peptide homing to ischemia/reperfusion injured cardiomyocytes (IRI-CM) was successfully displayed on the surface of exosomes by fusion to the N-terminus of lysosome associated membrane glycoprotein-2b (LAMP-2b) by genetic engineering, and the targeted delivery to IRI-CM was evaluated in vitro and in vivo.
As a proof of concept, FLAG, a synthetic tag was successfully displayed on the surface of exosomes, which was confirmed by immunprecipitated with anti-FLAG antibody and immunobloted with anti-CD63 antibody recognizing CD63, a marker of exosomes. Exosomes displaying peptide targeting ischemia/reperfusion injured cardiomyocytes were internalized preferentially onto IRI-CM relative to cardiomyocytes under normaxia both in vitro and in vivo.
A peptide homing to IRI-CM was successfully displayed on the surface of exosomes. These genetic engineered exosomes preferentially internalize into IRI-CM relative to cadiomyocytes under normoxia and thus can be exploited for targeted gene therapy for cardiac ischemia/reperfusion injury.