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Bertin, S.

Publications and source records attributed to Bertin, S..

5 recordsLinked to original sources

Multi-omics profiling reveals microenvironmental remodeling as a key driver of house dust mite-induced lung cancer progression

Chronic exposure to the common aeroallergen house dust mite (HDM) induces lung inflammation and DNA damage, but its impact on lung cancer development remains largely unexplored. Using whole-genome sequencing, RNA-seq, and DNA methylation profiling, we assessed HDM effects in lung epithelial cell lines and a mouse orthotopic lung cancer model. HDM accelerated tumor growth without altering mutational burden. Transcriptomic and epigenetic analyses revealed tissue-specific effects: in normal lung, HDM enhanced pro-inflammatory and immune activation programs, whereas in tumors it suppressed T cell responses, antigen presentation, and chemokine signaling. Immune deconvolution showed a shift toward myeloid enrichment and lymphoid suppression, with reduced cytotoxic T and NK signatures. Notably, HDM-driven tumor promotion was abolished in Il17a-/- but not Il1b-/-mice, identifying IL-17A as a critical mediator. These findings demonstrate that chronic aeroallergen exposure reshapes the lung microenvironment to promote immune suppression and accelerate lung cancer progression. HighlightsChronic house dust mite (HDM) exposure accelerates lung tumor growth through non-mutagenic, immune-mediated mechanisms. HDM activates pro-inflammatory and immune programs in normal lung tissue but suppresses antitumor T cell responses in tumors. Multi-omics profiling reveals epigenetic silencing of immune genes and a myeloid-enriched, lymphoid-deficient tumor microenvironment. HDM-driven tumor promotion depends on IL-17A but not IL-1{beta}, establishing IL-17A as a central driver of lung tumor promotion.

cancer biology↗

Inducible non-human primate models of retinal degeneration for testing end stage therapies and understanding disease mechanisms

The anatomical differences between the retinas of humans and most animal models pose a challenge for testing novel therapies. Non-human primate (NHP) retina is anatomically closest to the human retina with the presence of a high acuity region called the fovea. However, there is a lack of relevant NHP models for retinal degeneration that can be used for preclinical studies of vision restoration. To address this unmet need we aimed to generate inducible NHP models of photoreceptor degeneration. We generated three cynomolgus macaque models using distinct strategies. We used two genetically targeted strategies using optogenetics and Crispr-Cas9 to ablate specifically rods to mimic rod-cone dystrophy. Additionally, we created an acute model by physical separation of the photoreceptors and retinal pigment epithelium using a polymer patch. Retinal degeneration was evaluated in all three models by in-life exams such as fundus imaging, optical coherence tomography, adaptive optics and electroretinography. In the genetic models we observed punctuate areas of degeneration in the injected area marked by disorganization of outer segments, loss of rod photoreceptors and thinning of the outer nuclear layer. In the acute model, the degeneration was faster and involved both rods and cones. Among the three distinct NHP models, the Crispr-Cas9 based approach was the most advantageous model in view of recapitulating disease specific features and its ease of implementation. The acute model however resulted in the fastest degeneration making it the most relevant model for testing end-stage vision restoration therapies such as stem cell transplantation.

bioengineering↗

Gnas ablation in CD11c+ cells prevents high-fat diet-induced obesity by elevating adipose tissue catecholamine levels and thermogenesis

CD11c+ immune cells are a potential therapeutic target for treatment of obesity-related insulin resistance and type 2 diabetes (T2D). In obesity, CD11c+ immune cells are recruited to white adipose tissue and create an inflammatory state that causes both insulin and catecholamine resistance. In this study, we found that ablation of Gnas, the gene that encodes Gas, in CD11c expressing cells protects mice from high-fat diet-induced obesity, glucose intolerance and insulin resistance. Gnas{Delta}CD11c mice (KO) had increased oxygen consumption, energy expenditure, and beigeing of white adipose tissue (WAT). Transplantation studies showed that the lean phenotype was conferred by bone marrow-derived cells and the absence of T and B cells by crossing the KO to a Rag1-/- background did not alter the phenotype. Notably, we observed elevated norepinephrine and elevated cAMP signaling in the WAT of KO mice. The KO adipose tissue also had reduced expression of catecholamine transport and degradation enzymes. Collectively, our results identified an important role of Gas in CD11c+ cells in whole body metabolism regulation by controlling norepinephrine levels in WAT, modulating catecholamine-induced lipolysis and increasing thermogenesis that together created a lean phenotype.

immunology↗

Systemic and local immune response to intraocular AAV vector administration in non-human primates

The positive clinical outcomes in adeno-associated virus (AAV)-mediated retinal gene therapy have often been attributed to the low immunogenicity of AAVs along with the immune-privilege of the eye. However, several recent preclinical studies and clinical trials have shown potential for inflammatory responses to AAV mediated gene therapy. Our current understanding of the factors contributing to intraocular inflammation such as the existence of serum antibodies against AAVs prior to injection and their contribution to increases in antibody levels post-injection is incomplete. The parameters that regulate the generation of new antibodies in response to the AAV capsid or transgene post-injection after intraocular administration are also insufficiently described. In this study we carried out a retrospective analysis of the pre-existing serum antibodies in correlation with changes in antibody levels after intraocular injections of AAV in non-human primates (NHPs). We analyzed NHP serums for the presence of both Binding Antibodies (BABs), as well as a subset of these called Neutralizing Antibodies (NABs) that impede AAV transduction upon binding. We observed significantly higher pre-existing serum BABs against AAV8 compared to other serotypes. We observed a dose-dependent increase in both BABs and NABs in the serums collected post-injection, irrespective of the serotype or the mode of injection. Lastly, we were able to demonstrate a co-relation between the serum BAB levels with clinical grading of inflammation and levels of transgene expression.

immunology↗

Optogenetic therapy: High spatiotemporal resolution and pattern recognition compatible with vision restoration in non-human primates

Restoring vision using optogenetics is an ideal medical application because the eye offers a direct window to access and stimulate the pathological area: the retina. Optogenetic therapy could be applied to diseases with photoreceptor degeneration such as retinitis pigmentosa. Here, we select the specific optogenetic construct that is now used in the clinical trial and assess the opsin functional efficacy on non-human primates retinal ganglion cells (RGCs). We chose the microbial opsin ChrimsonR and showed that the vector AAV2.7m8 produced greater transfection in RGCs compared to AAV2, and that ChrimsonR attached to tdTomato (ChR-tdT) is more efficiently expressed than ChrimsonR. The 600 nm light activates the RGCs transfected with the vector AAV2.7m8-ChR-tdT from an irradiance of 1015 photons.cm-2.s-1. Vector doses of 5.1010 and 5.1011 vg/eye transfect up to 7000 RGCs/mm2 in the perifovea, with no significant immune reaction. Furthermore, using a multielectrode array we recorded RGCs responses starting from 1ms stimulus duration. Using the recorded activity we were able to decode stimulus information and estimate a theoretical visual acuity of 20/249, above legal blindness. Altogether, our results pave the way for the ongoing clinical trial with the AAV2.7m8-ChrimsonR-tdT vector for vision restoration in patients affected by retinitis pigmentosa. One Sentence SummaryWe select here the vector and genetic construct best suited to provide vision restoration in patients suffering from retinopathies, we demonstrate temporal resolution compatible with high dynamic visual scenes and a visual acuity above legal blindness.

neuroscience↗