Recombinant adeno-associated virus (rAAV) vectors are currently the only proven vehicles for treating ophthalmological diseases through gene therapy. A wide range of gene therapy programs that target ocular diseases are currently being pursued. Nearly 20 years of research have gone into enhancing the efficacy of targeting retinal tissues and improving transgene delivery to specific cell types. The engineered AAV capsid, AAV2.7m8 is currently among the best capsids for transducing the retina following intravitreal (IVT) injection. However, adverse effects, including intraocular inflammation, have been reported following retinal administration of AAV2.7m8 vectors in clinical trials. Furthermore, we have consistently observed that AAV2.7m8 exhibits low packaging titers irrespective of the vector construct design. In this report, we found that AAV2.7m8 packages vector genomes with a higher degree of heterogeneity than AAV2. We also found that genome-loaded AAV2.7m8 stimulated the infiltration of microglia in mouse retinas following IVT administration, while the response to genome-loaded AAV2 and empty AAV2.7m8 capsids produced much milder responses. This finding suggests that IVT administration of AAV2.7m8 vectors may stimulate retinal immune responses in part because of its penchant to package and deliver non-unit length genomes.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC11600122 | PMC |
http://dx.doi.org/10.1038/s41434-024-00477-7 | DOI Listing |
Hum Gene Ther
November 2022
Drug Discovery Sciences, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riss, Germany.
Adeno-associated viruses (AAVs) represent highly attractive gene therapy vectors and potent research tools for the modulation of gene expression in animal models or difficult-to-transfect cell cultures. Engineered variants, comprising chimeric, mutated, or peptide-inserted capsids, have strongly broadened the utility of AAVs by altering cellular tropism, enabling immune evasion, or increasing transduction efficiency. In this work, the performance of 50 of the most used, predominantly published, AAVs was compared on several primary cells, cell lines, and induced pluripotent stem cell-derived models from different organs, including the adipose tissue, liver, lung, brain, and eyes.
View Article and Find Full Text PDFHum Gene Ther
February 2022
Department of Genetic Medicine, Weill Cornell Medical College, New York, New York, USA.
Intravenous (IV) administration of naturally occurring adeno-associated virus (AAV) vectors are liver tropic, with a significant proportion of the total vector dose mediating gene expression in liver hepatocytes. AAV capsids that are directed toward other organs such as lung may be useful for therapy of nonliver-based diseases. Based on the knowledge that the lung capillary endothelium is the first capillary bed encountered by an intravenously administered AAV vector, and that the lung endothelium glycocalyx is enriched in negatively charged sialic acid, we hypothesized that adding positively changed lysine residues to the AAV capsid would enhance AAV biodistribution to the lung after IV administration.
View Article and Find Full Text PDFGene Ther
November 2022
Koret School of Veterinary Medicine, Hebrew University of Jerusalem, Rehovot, Israel.
Sheep carrying a mutated CNGA3 gene exhibit diminished cone function and provide a naturally occurring large animal model of achromatopsia. Subretinal injection of a vector carrying the CNGA3 transgene resulted in long-term recovery of cone function and photopic vision in these sheep. Research is underway to develop efficacious vectors that would enable safer transgene delivery, while avoiding potential drawbacks of subretinal injections.
View Article and Find Full Text PDFInt J Mol Sci
February 2020
Institut de la Vision, Sorbonne Université, INSERM, CNRS, 75012 Paris, France.
Human induced pluripotent stem cells (hiPSCs) promise a great number of future applications to investigate retinal development, pathophysiology and cell therapies for retinal degenerative diseases. Specific approaches to genetically modulate hiPSC would be valuable for all of these applications. Vectors based on adeno-associated virus (AAV) have shown the ability for gene delivery to retinal organoids derived from hiPSCs.
View Article and Find Full Text PDFBiotechnol Bioeng
December 2016
Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Institut de la Vision, 17 rue Moreau, Paris 75012, France.
Recently, we described a modified AAV2 vector-AAV2-7m8-having a capsid-displayed peptide insertion of 10 amino acids with enhanced retinal transduction properties. The insertion of the peptide referred to as 7m8 is responsible for high-level gene delivery into deep layers of the retina when virus is delivered into the eye's vitreous. Here, we further characterize AAV2-7m8 mediated gene delivery to neural tissue and investigate the mechanisms by which the inserted peptide provides better transduction away from the injection site.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!