rAAV6-mediated miR-29b delivery suppresses renal fibrosis
Previous studies showed that microRNA-29b (miR-29b) inhibits renal fibrosis. Therefore, miR-29b replacement therapy represents a promising approach for treating renal fibrosis. However, an efficient method of kidney-targeted miRNA delivery has yet to be established. Recombinant adeno-associated virus (rAAV) vectors have great potential for clinical application. For kidney-targeted gene delivery, the most suitable AAV serotype has yet to be established. Here, we identified the most suitable AAV serotype for kidney-targeted gene delivery and determined that AAV-mediated miR-29b delivery can suppress renal fibrosis in vivo.
To determine which AAV serotype is suitable for kidney cells, GFP-positive cells were identified by flow cytometry after the infection of rAAV serotype 1–9 vectors containing the EGFP gene. Next, we injected rAAV vectors into the renal pelvis to determine transduction efficiency in vivo. GFP expression was measured seven days after injecting rAAV serotype 1–9 vectors carrying the EGFP gene. Finally, we investigated whether rAAV6-mediated miR-29b delivery can suppress renal fibrosis in UUO mouse model.
We found that rAAV6 vector is the most suitable for targeting kidney cells regardless of animal species in vitro and rAAV6 is the most suitable vector for kidney-targeted in vivo gene delivery in mice. Intra-renal pelvic injection of rAAV vectors can transduce genes into kidney TECs. Furthermore, rAAV6-mediated miR-29b delivery attenuated renal fibrosis in UUO model by suppressing Snail1 expression.
Our study has revealed that rAAV6 is the most suitable serotype for kidney-targeted gene delivery and rAAV6-mediated miR-29b delivery into kidney TECs can suppress established renal fibrosis.
KeywordsAAV miRNA miR-29b Renal fibrosis
We thank Dr. Riichi Takahashi and Dr. Motohito Goto of Central Institute for Experimental Animals (CIEA) for supporting our in vivo analysis. This research was supported by a Grants-in-Aid for scientific research (B: 17H04067) and (17K16101) and by the Development program of microRNA measurement technology foundation in body fluid from Japan Agency for Medical Research and development, AMED and supported in part by Strategic Research Foundation Grant-aided Project for Private Universities from the Ministry of Education, Culture, Sports, Science and Technology of Japan.
- 2.Grande MT, Sanchez-Laorden B, Lopez-Blau C, De Frutos CA, Boutet A, Arevalo M, et al. Snail1-induced partial epithelial-to-mesenchymal transition drives renal fibrosis in mice and can be targeted to reverse established disease. Nat Med. 2015;21(9):989–97. https://doi.org/10.1038/nm.3901.CrossRefPubMedGoogle Scholar
- 6.Borges FT, Melo SA, Ozdemir BC, Kato N, Revuelta I, Miller CA, et al. TGF-beta1-containing exosomes from injured epithelial cells activate fibroblasts to initiate tissue regenerative responses and fibrosis. J Am Soc Nephrol. 2013;24(3):385–92. https://doi.org/10.1681/ASN.2012101031.CrossRefPubMedGoogle Scholar
- 7.Kriegel AJ, Liu Y, Fang Y, Ding X, Liang M. The miR-29 family: genomics, cell biology, and relevance to renal and cardiovascular injury. Physiol Genomics. 2012;44(4):237–44. https://doi.org/10.1152/physiolgenomics.00141.2011.CrossRefPubMedPubMedCentralGoogle Scholar
- 15.Samulski RJ, Muzyczka N. AAV-mediated gene therapy for research and therapeutic purposes. Annu Rev Virol. 2014;1(1):427–51. https://doi.org/10.1146/annurev-virology-031413-085355.CrossRefPubMedGoogle Scholar
- 17.Ito K, Chen J, Khodadadian JJ, Vaughan ED, Lipkowitz M, Poppas DP, et al. Adeno-associated viral vector transduction of green fluorescent protein in kidney: effect of unilateral ureteric obstruction. BJU Int. 2008;101(3):376–81. https://doi.org/10.1111/j.1464-410X.2007.07313.x.CrossRefPubMedGoogle Scholar
- 21.Takeda S, Takahashi M, Mizukami H, Kobayashi E, Takeuchi K, Hakamata Y, et al. Successful gene transfer using adeno-associated virus vectors into the kidney: comparison among adeno-associated virus serotype 1–5 vectors in vitro and in vivo. Nephron Exp Nephrol. 2004;96(4):e119–e12626. https://doi.org/10.1159/000077378.CrossRefPubMedGoogle Scholar