Biology subjects

Drack, A. V.

Publications and source records attributed to Drack, A. V..

3 recordsLinked to original sources

bioRxiv2025

Therapeutic antisense oligonucleotide mitigates retinal dysfunction in a pig model of CLN3 Batten disease

CLN3 Batten disease is a lethal pediatric autosomal recessive neurodegenerative disease caused by mutations in the CLN3 gene. Typically, the disease manifests as vision loss early in life and progresses to neurological dysfunction and death in young adulthood. Therapeutic development has focused on treating the central nervous system. However, such therapies may not protect against vision loss, which has a significant impact on quality of life. We have shown that a splice-switching antisense oligonucleotide (ASO) delivered to the central nervous system can reduce neurological disease burden in mouse models of CLN3 disease. Here, we report on a similar ASO approach for treating CLN3 Batten disease retinal dysfunction in a pig model of the disease, which is more representative of human vision. A single intravitreal injection of ASO induces robust exon skipping in the retina for up to 12 months. The ASO treatment resulted in higher amplitudes on electroretinograms, suggesting mitigation of retinal dysfunction at early timepoints of disease. One ASO that efficiently induces exon skipping in vivo was well-tolerated and targets a region of CLN3 that is conserved in humans, making it a promising candidate for treating the disease in humans. Our findings demonstrate the potential utility of an ASO-based approach to treat retinal dysfunction in CLN3 Batten disease and generally supports the use of ASOs for treating eye diseases. One Sentence SummarySplice-switching antisense oligonucleotides delivered by intravitreal injection are safe and show efficacy in preventing early retinal dysfunction in a pig model of CLN3 Batten disease.

molecular biology↗

bioRxiv2024

Delivering large genes using adeno-associated virus and the CRE-lox DNA recombination system

Adeno-associated virus (AAV) is a safe and efficient gene delivery vehicle for gene therapies. However, its relatively small packaging capacity limits its use as a gene transfer vector. Here, we describe a strategy to deliver large genes that exceed the AAVs packaging capacity using up to four AAV vectors and the CRE-lox DNA recombination system. We devised novel lox sites by combining non-compatible and reaction equilibrium-modifying lox site variants. These lox sites facilitate sequence-specific and near-unidirectional recombination of AAV vector genomes, enabling efficient reconstitution of up to 16 kb of therapeutic genes in a pre-determined configuration. Using this strategy, we have developed AAV gene therapy vectors to deliver IFT140, PCDH15, CEP290, and CDH23 and demonstrate efficient production of full-length proteins in cultured mammalian cells and mouse retinas. Notably, this approach significantly surpasses the trans-splicing and split-intein-based reconstitution methods in efficiency, requiring lower doses, minimizing or eliminating the production of truncated protein products, and offering flexibility in selecting splitting positions. The CRE-lox approach described here provides a simple and effective platform for producing AAV gene therapy vectors beyond AAVs packaging capacity.

molecular biology↗

bioRxiv2022

Knockout of Bbs10 results in lack of cone electrical function and progressive retinal degeneration of rods and cones

Bardet Biedl Syndrome (BBS) is an autosomal recessive disorder caused by mutations in at least 22 different genes. A constant feature is early onset retinal degeneration leading to blindness, with variable central obesity, polydactyly, renal failure, and developmental anomalies. BBS type 10 (BBS10) is a common form caused by mutations in the BBS10 gene encoding a chaperonin-like protein. There are currently no treatments for the progressive vision loss. To aid in treatment development, a BBS10 mouse model was developed by knocking out the Bbs10 gene. Using optical coherence tomography (OCT), electroretinography (ERG), and a visually guided swim assay (VGSA), we demonstrate that Bbs10-/- mice have progressive retinal degeneration. Cone electrical function was absent although cones were anatomically present on histology and retained partial function based on VGSA. The retinal outer nuclear layer (photoreceptor nuclei) progressively thinned as demonstrated on OCT and histology, and rod electrical activity decreased over time on ERG. These phenotypes are more rapidly progressive than retinal degeneration in the Bbs1M390R/M390R knock-in mouse. They are consistent with a cone-rod dystrophy distinct from typical rod-cone degeneration in retinitis pigmentosa and recapitulate aspects of retinal degeneration observed in humans with BBS10. This study has implications for BBS10 gene therapy.

genetics↗