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Maturana, C. J.

Publications and source records attributed to Maturana, C. J..

2 recordsLinked to original sources

The Alphaherpesvirus Latency Associated Promoter 2 (LAP2) Drives Strong Transgene Expression in Peripheral Tissue Depending on Administration Route and AAV Serotype

Adeno-associated virus (AAV) has shown great translational potential in treating a variety of diseases often requiring strong and ubiquitous transgene expression. However, the genetic payload of AAV vectors is limited to <4.9 kb and some commonly used gene promoters are large in sizeable and susceptible to transcriptional silencing. We validated a short (404 bp), strong and persistent promoter obtained from the genome of pseudorabies virus (PRV) called alphaherpesvirus latency-associated promoter 2 (LAP2). We evaluated the biodistribution and potency of transgene expression in mouse peripheral tissue and organs when using AAV8-LAP2 and AAV9-LAP2, both of which achieved transgene expression like that of the ubiquitous promoter, EF1. LAP2 drives potent transgene expression in liver and kidney after systemic retro-orbital administration and in skeletal muscle after intramuscular delivery. Additionally, we observed broad transduction throughout the lung albeit at lower levels than other tissues. Notably, in skeletal muscle LAP2 resulted in preferential transduction of myofiber types 2. A direct side-by-side comparison between LAP2 and EF1, demonstrates that regardless of the AAV serotype and route of administration, LAP2 is as powerful and persistent as EF1 promoter despite being 66% smaller in size, thus allowing for larger therapeutic payloads.

cell biology↗

SMALL ALPHAHERPESVIRUS LATENCY-ASSOCIATED PROMOTERS DRIVE EFFICIENT AND LONG-TERM TRANSGENE EXPRESSION IN THE CENTRAL NERVOUS SYSTEM

Recombinant adeno-associated viral vectors (rAAV) are used as gene therapy vectors to treat central nervous system (CNS) diseases. Despite their safety and broad tropism, important issues need to be corrected such as the limited payload capacity and the lack of small gene promoters providing long-term, pan-neuronal transgene expression in the CNS. Commonly used gene promoters are relatively large and can be repressed a few months after CNS transduction, risking the long-term performance of single-dose gene therapy applications. We used a whole-CNS screening approach based on systemic delivery of AAV-PHP.eB, iDisco+ tissue-clearing and light-sheet microscopy, to identify three small latency-associated promoters (LAP) from the herpesvirus pseudorabies virus (PRV). These promoters are LAP1 (404bp), LAP2 (498bp) and LAP1_2 (880bp). They drive chronic transcription of the virus encoded latency-associated transcript (LAT) during productive and latent phases of PRV infection. We observed stable, pan-neuronal transgene transcription and translation from AAV-LAP in the CNS for six months post AAV transduction. In several CNS areas, the number of cells expressing the transgene was higher for LAP2 than the large conventional EF1 promoter (1264bp). Our data suggests that the LAP are suitable candidates for viral vector-based CNS gene therapies requiring chronic transgene expression after one-time viral-vector administration.

neuroscience↗