Biology subjects

Blouin, V.

Publications and source records attributed to Blouin, V..

2 recordsLinked to original sources

bioRxiv2026

Intracellular accumulation of AAV6 genomes governs microglia reactivity and the inflammatory response in retinal gene therapy

Adeno-associated viral (AAV) vectors possess immense potential for gene therapy applications. However, microglia can mount an immune response against AAV vectors. Yet, microglia are therapeutic targets since they play a driving role in the progression of neurodegenerative diseases. Thus, it is critical to understand the cellular processes driving the microglia-mediated immune response against AAV vectors. To this end, we modelled AAV6 induced inflammation upon retinal gene therapy in minipigs. Upon AAV6 administration, the IBA1+ cells demonstrated a morphological transition to the amoeboid form, indicating microglial reactivity. We also observed the invasion of peripheral immune cells in the retina. To elucidate the underlying molecular mechanisms, we transduced human iPSC derived microglia-like cells (iMGLs) in vitro with AAV6 and AAV8 respectively. Only AAV6 transduced iMGLs exhibited morphological features and a transcriptomic signature of microglial reactivity. The magnitude of intracellular AAV6 viral genomes was significantly higher as compared to the AAV8 condition. The elevated levels of intracellular AAV6 genomes induced a DNA damage response in AAV6-transduced iMGLs, which is a key feature of neuroinflammation-linked microglial reactivity. Thus, our work highlights the impact of intracellular viral genome accumulation on microglial reactivity and its implications for retinal gene therapy associated inflammation.

neuroscience↗

bioRxiv2022

AAV2/9-mediated gene transfer into murine lacrimal gland leads to a long-term targeted tear film modification

Corneal blindness is the fourth leading cause of blindness worldwide. Since the corneal epithelium is constantly renewed, non-integrative gene transfer cannot be used to treat corneal diseases. In numerous of these diseases, the tear film has been reported to be defective. Tears are a complex biological fluid secreted by the lacrimal apparatus. Their composition is modulated according to the context. For instance, after a corneal wound, the lacrimal gland secretes reflex tears, which contain specific growth factors supporting the wound healing process. In specific pathological contexts, such as dry eye diseases, the tear composition can support neither corneal homeostasis, nor wound healing. Here, we propose to use the lacrimal gland as bioreactor to produce and secrete specific factors to support corneal physiology. In this study, we used an AAV2/9-mediated gene transfer to supplement the tear film. First, we demonstrate that a single injection of AAV2/9 is sufficient to transduce all epithelial cell types of the lacrimal gland efficiently and widely. Then, we show that lacrimal gland physiology and corneal integrity are maintained after the injection of an AAV2/9-mediated nerve growth factor expression in the lacrimal gland. Remarkably, this injection induces an important and long-lasting secretion of this growth factor in the tear film. Altogether, our findings provide a new clinically applicable approach to tackle corneal blindness.

physiology↗