Due to the poor healing capacity of tendons, the healing process is slow, with a risk of re-rupture post-injury. In this study, we found that miR-494-3p was one of the miRNAs with significant expression differences after...Due to the poor healing capacity of tendons, the healing process is slow, with a risk of re-rupture post-injury. In this study, we found that miR-494-3p was one of the miRNAs with significant expression differences after tendon injury by sequencing in the rat Achilles tendon injury model. Therefore, we hypothesized that regulating miR-494-3p expression in tendons could improve tendon healing. Considering the long healing process of the tendons and the short half-life of miRNA, we hope to achieve the best efficacy by delivering miR-494-3p using a sustained-release nanoparticle hydrogel system. In the results, with an increase in miR-494-3p, the tendon biomechanics were significantly improved after 2-week repair, and the content of collagen I (Col I) also increased. Through bioinformatics prediction, double luciferase, and immunohistochemistry experiments, we confirmed that miR-494-3p targeting CXXC finger protein 4 (CXXC4) promoted tendon healing. In conclusion, the miR-494-3p/nanoparticles hydrogel delivery system can protect and sustainedly transfer miR-494-3p into tenocytes, block the translation of CXXC4, increase the expression of Col I, and ultimately improve tendon healing. A nanoparticle hydrogel delivery system of miRNA was constructed and applied to injured tendons. Finally, we confirmed that the miR-494-3p/nanoparticles hydrogel delivery system can protect and sustainedly transfer miR-494-3p into tenocytes, block the translation of CXXC4, increase the expression of Col I, and ultimately improve tendon healing.
Jalatyan T, Aznauryan E, Hasan R
… +10 more, Vardanyan V, Nersisyan S, Thompson DB, Davidsohn N, Thomas S, van Haren S, Tam J, Milanova D, Church GM, Nersisyan L
Naturally occurring adeno-associated viruses (AAVs) are an integral part of gene therapy, yet engineering novel AAV variants is necessary to expand targetable tissues and treatable diseases. Directed evolution, particula...Naturally occurring adeno-associated viruses (AAVs) are an integral part of gene therapy, yet engineering novel AAV variants is necessary to expand targetable tissues and treatable diseases. Directed evolution, particularly through DNA shuffling of the capsid genes of wild-type AAV serotypes, is a widely employed strategy to generate novel chimeric variants with desired properties. Yet, the computational analysis of such chimeric sequences presents challenges. We introduce hafoe, a novel computational tool designed for the exploratory analysis of chimeric AAV libraries, which does not require extensive bioinformatics expertise. hafoe accurately deciphers the serotype composition and enrichment patterns of chimeric AAV variants across different tissues. Validation against synthetic datasets demonstrates that hafoe identifies parental serotype compositions with an accuracy of 96.3% to 97.5%. Additionally, we engineered chimeric AAV capsid libraries and screened novel AAV variants for tropism to human dermal fibroblasts and dendritic cells, as well as canine muscle, and liver tissues. Using hafoe we identified and characterized enriched AAV variants in these tissues for potential use in gene therapy and vaccine development. Overall, hafoe can provide valuable insights that may further support the rational design of AAV vectors based on parental serotype and sequence preferences of the capsid genes in target tissues.
Gaucher disease (GD) is a rare genetically inherited illness caused by loss of lysosomal acid β-glucosidase (β-GCase) that leads to progressive accumulation of substrates, sphingolipid glucosylceramide (GL1) and glucosyl...Gaucher disease (GD) is a rare genetically inherited illness caused by loss of lysosomal acid β-glucosidase (β-GCase) that leads to progressive accumulation of substrates, sphingolipid glucosylceramide (GL1) and glucosylsphingosine (lyso-GL1). The protein-based enzyme replacement therapy (ERT) requires frequent dosing due to short drug half-life causing challenges in long-term patient compliance. JCXH-301 is a lipid nanoparticle (LNP) encapsulated messenger RNA (mRNA) encoding β-GCase. Intravenous administration of JCXH-301 delivered the target mRNA to various tissues in mice with intracellular expression of β-GCase predominantly in macrophages and dendritic cells in the spleen and bone marrow. In GBA1 D427V homozygous mice treated with JCXH-301, the dose-dependent in vivo production of functional β-GCase resulted in reduction of serum lyso-GL1, a key biomarker of GD. The therapeutic effect of JCXH-301 was sustained for a duration significantly longer than that of protein-based ERT Cerezyme. JCXH-301 administration induced minimal pro-inflammatory cytokines in the liver and spleen. Taken together, these results provide proof-of-concept for using LNP-delivered mRNA as a new drug modality to restore the β-GCase genetic deficiency for GD treatment.
Adenosine deaminase type 2 deficiency (DADA2) is caused by bi-allelic loss-of-function mutations in ADA2. While anti-TNF therapy is effective for the autoinflamatory and vasculitic components of the disease it does not c...Adenosine deaminase type 2 deficiency (DADA2) is caused by bi-allelic loss-of-function mutations in ADA2. While anti-TNF therapy is effective for the autoinflamatory and vasculitic components of the disease it does not correct marrow failure or immunodeficiency. Allogeneic stem cell transplantation (HSCT) offers a potential cure but is limited by challenges such as graft-versus-host-disease and donor availability. We previously demonstrated that lentiviral-mediated ADA2 gene therapy could restore ADA2 enzyme activity in patient-derived cells, correct macrophage inflammatory activation and reduce endothelial activation in vitro. Here, we evaluated the biodistribution and engraftment potential of lentivirally transduced healthy donor and patient-derived haematopoietic stem cells (HSC) in vivo using a humanised NBSGW mouse model. Transduced healthy HSC retained multilineage differentiation and engraftment capacity, without functional impairment. PCR analysis confirmed the absence of viral integration in non-haematopoietic organs, and histology showed no abnormal tissue changes, underscoring the safety and precision of this approach. In DADA2 patient-derived HSC, ADA2 transduction restored protein expression and enzyme activity, supporting improved cellular function and enhanced engraftment potential. These findings provide a strong foundation for advancing ADA2 gene therapy as a therapeutic strategy for DADA2, bringing it closer to clinical application.
Optimization of recombinant adeno-associated virus (rAAV) production is essential for effective gene therapy applications. However, multiple factors affect the rAAV productivity in mammalian cells, and often they interac...Optimization of recombinant adeno-associated virus (rAAV) production is essential for effective gene therapy applications. However, multiple factors affect the rAAV productivity in mammalian cells, and often they interact with each other, making the optimization process highly challenging. In our previous work, we showed how coupling mixture design (MD) with face-centered central composite design (FCCD) was the most suitable design of experiments (DOE) approach for optimizing rAAV2 productivity and cell viability. In this study, we built on this method and demonstrate that combining MD with FCCD can be used to optimize the percentage of full capsids in rAAV2 upstream preparation. Additionally, we investigate the influence of the gene of interest (GOI) on the optimal conditions for viral particle production and packaging efficiency. By integrating MD and FCCD methodologies, we achieved an improvement of almost 100-fold in Log(Vp) in the case of egfp-expressing rAAV, and a 12-fold increase in bdnf-expressing full rAAV capsids, suggesting that this combined approach is a versatile and effective strategy for optimizing rAAV production processes. These findings emphasize the need for a comprehensive understanding of the factors influencing rAAV production to enhance the efficiency and efficacy of viral vector applications in gene therapy.
Camelo CG, Mendonça RH, Moreno CAM
… +11 more, Ferreira JCOA, Ortega AB, van der Linden V, Campos RSM, van der Linden H, da Cunha NSC, Gurgel-Giannetti J, Chaves JM, Miranda SMC, Ziegler A, Zanoteli E
Onasemnogene abeparvovec (OA) is the first gene replacement therapy (GT) approved for 5q spinal muscular atrophy (SMA). While effective, it can cause severe side effects, including thrombotic microangiopathy (TMA). The p...Onasemnogene abeparvovec (OA) is the first gene replacement therapy (GT) approved for 5q spinal muscular atrophy (SMA). While effective, it can cause severe side effects, including thrombotic microangiopathy (TMA). The pathophysiology, risk factors, and management of viral-vector-related TMA remain unclear. This study aimed to evaluate TMA frequency among Brazilian patients treated with OA and characterize their clinical and laboratory profiles. This retrospective, multicenter study analyzed 294 Brazilian patients with 5q SMA treated with OA between October 2020 and September 2024, of whom seven (2.4%) developed TMA. The average age at OA administration was 20.4 months, and the average weight was 11.5 kg. Three patients had documented infections before OA administration. TMA symptoms appeared within 6-10 days post-infusion. All patients showed hemolytic anemia, thrombocytopenia, and at least one organ dysfunction. Treatment included plasmapheresis in two cases and increased corticosteroid doses in four cases. One patient died from TMA complications. Whole exome sequencing in five patients identified no pathogenic variants linked to TMA. TMA is a rare but severe complication of OA therapy for SMA. Prompt recognition and management, often with corticosteroids, are crucial for improving outcomes.
The treatment of chronic disease (CKD) is a great challenge in healthcare that requires an innovative approach to address its complex nature. RNA nanotechnology has emerged rapidly and received attention in the last few...The treatment of chronic disease (CKD) is a great challenge in healthcare that requires an innovative approach to address its complex nature. RNA nanotechnology has emerged rapidly and received attention in the last few years because of its significant aptitude for therapies. Hence, the present study aimed to design, construct, and characterize a multifunctional (anti-miR-34a DNA aptamer-kidney targeted) RNA nanoparticle (RNPs) based on bacteriophage phi29 packaging RNA three-way junction (pRNA-3WJ), and then explore their in vivo toxicity and therapeutic potentials in mice model of CKD. After confirming the safety and specific targeting capability of the prepared core 3WJ (3WJ) and the therapeutic 3WJ (3WJ-Kapt/anti-miR-34a) RNPs to renal tissue using healthy mice, CKD was induced in C57BL/6 mice using adenine. CKD mice were treated with a single intravenous injection of 3WJ or 3WJ-Kapt/anti-miR-34a. Every week, 5 mice of each group were selected randomly for sample collection for 4 weeks post-treatment. The anti-miR-34a 3WJ-RNPs have shown stability, safety, and efficacy in renal targeting using DNA aptamer, by targeting miR-34a in renal tissue, 3WJ-Kapt/anti-miR-34a suppressed profibrotic gene expression and induced anti-fibrotic pathways' expression. Our present study provides preliminary and pioneering evidence for the promising treatment of renal fibrosis and CKD through targeting miR-34a in the renal tissue by 3WJ-RNPs. The CKD mice showed marked time-dependent up-regulation of the renal profibrotic pathways, including TGF-β, FGF2, and WNT/β-catenin pathways. The same mice showed suppressed renal expression of the antifibrotic pathways, including α and β Klotho, SMAD7, and SIRT1. The prepared anti-miR-34a 3WJ-RNPs have shown stability, safety, and efficacy in renal targeting using DNA aptamer. By targeting miR-34a in renal tissue, 3WJ-Kapt/anti-miR-34a suppressed profibrotic gene expression and induced anti-fibrotic pathways' expression. Our present study provides preliminary and pioneer evidence for the promising treatment of renal fibrosis and CKD through targeting miR-34a in the renal tissue by 3WJ-RNPs.
Abou Haidar E, Prabhakar S, Cheah PS
… +16 more, Hanlon KS, Espinoza P, Crain AV, Patel N, Radcliff GW, Cheng M, Hernández IC, Minderler S, de la Cruz D, Ng C, da Hora CC, Charest A, Stemmer-Rachamimov A, Jowett N, Breakefield XO, Maguire CA
Genetic diseases such as Neurofibromatosis type 1 (NF1) and Charcot-Marie Tooth disease involve Schwann cells (SCs) associated with peripheral nerves. Gene therapy using adeno-associated virus (AAV) vector mediated gene...Genetic diseases such as Neurofibromatosis type 1 (NF1) and Charcot-Marie Tooth disease involve Schwann cells (SCs) associated with peripheral nerves. Gene therapy using adeno-associated virus (AAV) vector mediated gene delivery is a promising strategy to treat these diseases. However, AAV-mediated transduction of SCs in vivo after intravascular delivery is relatively inefficient, with a lack of extensive characterization of different capsids to date. Here, we performed an in vivo selection with an AAV9 capsid peptide display library in a mouse model of NF1. We chose one capsid variant, AAV-SC3, which was present in NF1 nerves for comparison to two benchmark capsids after systemic injection. AAV-SC3 significantly outperformed one of the two benchmark capsids at levels of transgene mRNA in the neurofibroma. Immunofluorescence microscopy revealed transgene expressing Sox10-positive SCs throughout the neurofibroma with AAV-SC3 injection. Next, we performed a pooled screen with four of the top capsids from our initial selection and AAV9 and identified one capsid, AAV-SC4, with enhanced biodistribution to and transduction of normal sciatic nerve in mice. This capsid displayed a peptide with a known laminin-binding motif, which may provide a conduit for future laminin-targeting strategies. Our results provide a baseline for future AAV-based gene therapies developed for NF1 or other diseases that affect SCs.
Heparin cofactor II (HCII) is a critical anticoagulant protein that inactivates thrombin. In our previous mouse studies, we demonstrated that GalNAc-HCII, a small interfering RNA (siRNA) targeting HCII conjugated with N-...Heparin cofactor II (HCII) is a critical anticoagulant protein that inactivates thrombin. In our previous mouse studies, we demonstrated that GalNAc-HCII, a small interfering RNA (siRNA) targeting HCII conjugated with N-acetylgalactosamine (GalNAc), exhibited promising therapeutic effects in hemophilia A mouse models. Further evaluation in large animal models, especially with FVIII inhibitors, is essential before GalNAc-HCII can proceed to clinical trials. In this study, we successfully established, for the first time, an acquired hemophilia A canine model by multiple intravenous injections of a rabbit-dog chimeric neutralizing anti-canine FVIII antibody. In the control group, the Beagle dogs exhibited spontaneous bleeding symptoms accompanied by prolonged activated partial thromboplastin time (APTT). After administration, GalNAc-HCII (0.8 and 1.6 mg/kg) demonstrated potent, dose-dependent, and durable HCII inhibitory effects. After 5 days, in normal dogs, GalNAc-HCII reduced HCII levels to 32.67% ± 3.07% and 10.62% ± 1.74% with 0.8 and 1.6 mg/kg GalNAc-HCII, respectively. In hemophilic dogs, GalNAc-HCII treatment significantly improved hemostatic function. Specifically, in the carotid artery thrombosis model, the thrombus formation time was shortened [29.7 ± 2.08 min (0.8 mg/kg) and 18.0 ± 1.0 min (1.6 mg/kg) vs. 40 min (control), P < 0.01]; in the knee joint puncture-induced bleeding model, joint bleeding and synovitis were alleviated; and in the saphenous vein bleeding model, the number of hemostatic events increased. Furthermore, repeated administration of GalNAc-HCII effectively reduced the prolonged APTT. This study demonstrates the efficacy of GalNAc-HCII in hemophilic dogs, suggesting it as a promising novel therapeutic option for patients with hemophilia, including those with FVIII inhibitors.
Liu L, Song L, Liu T
… +19 more, Hui K, Hu C, Yang J, Pi X, Yan Y, Liu S, Zhang Y, Chen H, Cao Y, Zhou L, Qiao Y, Yu D, Yin C, Li X, Zhang C, Li D, Wang Z, Liu Z, Jiang X
Resistance to radiotherapy is a significant challenge in the clinical management of non-small cell lung cancer (NSCLC). This study investigates a novel multimodal therapeutic strategy that combines oncolytic Newcastle di...Resistance to radiotherapy is a significant challenge in the clinical management of non-small cell lung cancer (NSCLC). This study investigates a novel multimodal therapeutic strategy that combines oncolytic Newcastle disease virus (NDV) with an anti-VEGFR2 single-chain variable fragment (NDV-anti-VEGFR2) to enhance radiosensitivity in NSCLC. We engineered NDV-anti-VEGFR2 and assessed its efficacy in sensitizing Calu-1 cells to radiation. In vitro results demonstrated that NDV-anti-VEGFR2 significantly inhibited tumor cell proliferation when combined with radiotherapy. In vivo experiments revealed that NDV-anti-VEGFR2, combined with radiation, achieved a tumor growth inhibition rate of 86.48%, surpassing the effects of NDV or radiation alone. Mechanistic investigations indicated that NDV-anti-VEGFR2 mitigated hypoxia by downregulating HIF-1α and impaired DNA repair pathways, as evidenced by reduced levels of RAD51 and γ-H2AX. These findings suggest that NDV-anti-VEGFR2 not only normalizes tumor vasculature but also enhances the cytotoxic effects of radiation by compromising DNA repair mechanisms. Collectively, our results support the clinical potential of NDV-anti-VEGFR2 combined with radiotherapy as a promising strategy to overcome radiotherapy resistance in NSCLC. Future studies in immunocompetent models are warranted to elucidate the immune-mediated effects of this innovative therapeutic approach.
Recombinant adeno-associated viruses (AAVs) have become increasingly popular as gene therapy vectors in recent years. Like all viruses, AAVs undergo dynamic structural changes in response to varying temperature and pH co...Recombinant adeno-associated viruses (AAVs) have become increasingly popular as gene therapy vectors in recent years. Like all viruses, AAVs undergo dynamic structural changes in response to varying temperature and pH conditions. However, the specific capsid regions involved in these processes remain unknown. In this study, we employed Hydrogen-Deuterium Exchange Mass Spectrometry (HDX-MS) to investigate the impact of pH and temperature on the structure and conformational dynamics of AAV capsids. Our analysis identified specific regions of the capsid that are sensitive to these environmental changes. Additionally, our data elucidated the structural basis for DNA uncoating or leakage triggered by low pH or high temperature. Detailed structural characterization of AAVs by HDX-MS in this study deepens our understanding of viral capsid conformational dynamics and stability in AAV transduction and manufacturing and storage conditions, paving the way for formulation development and next-generation capsid engineering.
Transcranial Magnetic Resonance Guided Focused Ultrasound can oscillate intravenously delivered microbubbles and transiently open the blood brain barrier (BBB) in a targeted brain region. However, high microbubble doses...Transcranial Magnetic Resonance Guided Focused Ultrasound can oscillate intravenously delivered microbubbles and transiently open the blood brain barrier (BBB) in a targeted brain region. However, high microbubble doses or Focused ultrasound pressures (FUS) leads to injury. So, we administered nitrous oxide (NO), an anesthetic gas to determine reduced need of FUS pressure and microbubble dose for opening BBB. Swiss Webster mice were treated with NO or medical air (MA) at varying FUS pressures, while the microbubble dose was kept constant and the vice-versa. Consequently, BBB opening was quantified by acoustic emissions and enhancement rate on T1-weighted MR. To compare the effect of NO on gene delivery, following BBB opening with either MA or NO, a viral vector expressing GFP was subsequently delivered. Additionally, Immunohistochemical studies quantified viral transfection efficacy and assessed acute cell injury. We observed that NO significantly potentiates acoustic emissions and enhancement rate on post-contrast MRI images, compared to MA at all measured pressures (0.39, 0.45, 0.67 MPa). Furthermore, NO reduces the microbubble dose to 0.02μl/kg and FUS pressures to 0.28 and 0.39 MPa for BBB disruption and enhanced viral gene delivery, respectively. Hence, NO potentiates microbubble oscillations, allowing reduced microbubble dose and FUS pressures and improved viral gene delivery.
Gene therapy with AAV vectors is a promising approach for treating numerous genetic disorders but is often hindered by preexisting antibodies that neutralize the vectors. Given that females may exhibit stronger immune re...Gene therapy with AAV vectors is a promising approach for treating numerous genetic disorders but is often hindered by preexisting antibodies that neutralize the vectors. Given that females may exhibit stronger immune responses than males, this study hypothesizes that females may have higher preexisting antibody titers against AAV. Serum samples from two U.S. cohorts were analyzed for antibody titers, antibody subtypes, and transduction inhibition activity against AAV serotypes AAV1, AAV2, AAV5, AAV8, and AAV9. We found that among seropositive samples, females had higher preexisting antibody levels and neutralizing activities against AAV9 and other serotypes. Immunoglobulin subclass analysis showed IgG1 dominance in both sexes, but females had higher IgA levels, whereas males had higher levels of IgG2. We further evaluated the cellular level of this differential immune response to AAV by stimulation of male and female human PBMCs. We observed dose-dependent increase in cytokines and chemokines in female PBMCs which suggests a differential inflammatory response. Altogether, our findings suggest that the enhanced immune response in females could lead to neutralization and faster clearance of AAV vectors with potential to impact the efficacy of gene therapy.
Chimeric peptides hold promising potential to be introduced as an ideal gene delivery platform based on their advantages over viral carriers, including but not limited to the safety profile and specific targeting. Howeve...Chimeric peptides hold promising potential to be introduced as an ideal gene delivery platform based on their advantages over viral carriers, including but not limited to the safety profile and specific targeting. However, their gene transfer efficiency needs improvement. Here, we designed a new multi-functional chimeric peptide for enhanced gene delivery by adding a cyclic TAT motif to a previously designed MPG2H peptide to enable the targeting of cells with independent/dependent endocytosis cell entry mechanisms. CTATMPG2H was expressed and purified using affinity chromatography; then it was characterized through a gel retardation assay, circular dichroism (CD) spectropolarimetry, transmission electron microscopy (TEM) dynamic light scattering (DLS), and zeta potential analysis. CTATMPG2H was compared with MiRGD as a chimeric peptide control in all steps. After assessing the platform stability in various conditions, its gene transfer efficiency was evaluated in the HEK293T cell line with reporter genes. Additionally, mouse bone marrow-derived dendritic cells (BMDCs) were transfected to test CTATMPG2H potential in immunotherapy. The results illustrated a safe gene transfer profile for CTATMPG2H comparable to MiRGD and Polyethyleneimine (PEI). Flow cytometry results showed up to 48% gene transfer rate for CTATMPG2H to dendritic cells with minimal toxicity (viability rate ~80%). Moreover, the in silico investigation showed that the synergistic effects of electrostatic, hydrogen, and hydrophobic interactions enhance the stability and binding affinity of peptide-pDNA complexes, ensuring robust and specific targeting of nucleic acids. This research sets a foundation for future in vivo studies and potential clinical applications, aiming for safer and more effective gene therapy strategies.
Supported by encouraging trial outcomes, onasemnogene abeparvovec (OA) was authorized for spinal muscular atrophy (SMA). Nevertheless, efficacy of OA in advanced SMA patients remains underexplored. This investigation ass...Supported by encouraging trial outcomes, onasemnogene abeparvovec (OA) was authorized for spinal muscular atrophy (SMA). Nevertheless, efficacy of OA in advanced SMA patients remains underexplored. This investigation assessed clinical effectiveness and adverse effects of OA in a cohort including advanced SMA, and compared to historical survival data for SMA type 1 patients in Thailand. We conducted observational cohort study at Siriraj Hospital, Thailand, from May 2019 to April 2022. The study enrolled eight SMA patients receiving OA therapy. The cohort comprised five SMA type 1 patients treated at 16.7 months (6.5-24.9 months) and three SMA type 2 patients treated at 20.3 months (19-31.5 months). Before receiving OA, all Type 1 patients required 24-hour invasive ventilation and feeding support. Post-treatment, Three of five showed gradual improvement in motor scores, but none achieved new motor milestones. Survival rate was not improved, with all experiencing fatalities. Conversely, Type 2 patients exhibited motor score improvement without serious adverse events. OA did not significantly improve clinical outcomes or survival rates in advanced Type 1 SMA. These findings highlight need for additional caution when administering OA to severe SMA Type 1 and more specific guidelines in selecting subgroups for treatment.
Filz von Reiterdank I, Mojoudi M, Bento R
… +8 more, Taggart MS, Dinicu AT, Wojtkiewicz G, Coert JH, Mink van der Molen AB, Weissleder R, Parekkadan B, Uygun K
Developing new strategies for local monitoring and delivery of immunosuppression is critical to making allografts safer and more accessible. Ex vivo genetic modification of grafts using machine perfusion presents a promi...Developing new strategies for local monitoring and delivery of immunosuppression is critical to making allografts safer and more accessible. Ex vivo genetic modification of grafts using machine perfusion presents a promising approach to improve graft function and modulate immune responses while minimizing risks of off-target effects and systemic immunogenicity in vivo. This proof-of-concept study demonstrates the feasibility of using normothermic machine perfusion (NMP) to mimic in vitro conditions for effective gene delivery. In this study, lentiviral vectors encoding the secreted biomarker Gaussia Luciferase (GLuc) and red fluorescent protein (RFP) were introduced ex vivo to rodent livers during a 72-h machine perfusion protocol. After an initial 24-h exposure to viral vectors, the organs were maintained in perfusion for an additional 48 h to monitor gene expression, aligning with in vitro benchmarks. Control livers were perfused in similar fashion, but without viral injections. Virally perfused livers exhibited nearly a 10-fold increase in luminescence compared to controls (p < 0.0001), indicating successful genetic modification of the organs. These findings validate the use of machine perfusion systems and viral vectors to genetically engineer whole organs ex vivo, laying the groundwork for a broad range of applications in transplantation through genetic manipulation of organ systems. Future studies will focus on refining this technology to enhance precision in gene expression and explore its implications for clinical translation.
Lentiviral vectors (LVVs) are widely used in gene therapy due to their ability to infect both dividing and non-dividing cells. For LVV production, the creation of stable packaging cell lines with integrated genes necessa...Lentiviral vectors (LVVs) are widely used in gene therapy due to their ability to infect both dividing and non-dividing cells. For LVV production, the creation of stable packaging cell lines with integrated genes necessary for viral replication offer a more consistent and scalable alternative to transient plasmid transfection approach. Although the development of such stable LVV packaging cell lines has been reported, the molecular changes induced by stable and inducible viral gene expression and the impact of genome integrated viral genes on cellular pathways remain poorly characterized. For better insight, we investigated the molecular characteristics of a stable LVV packaging cell line and its host cell line (HEK293T/17) by comparing differential expressed genes. This pathway analysis revealed significant changes in pathway usage between packaging and host cell lines, influenced by different viral transgenes. Gag-pol expression was found to suppress host translational machinery, while rev and VSV-G expression modulated mitochondrial pathways, including oxidative phosphorylation. HIV-1 tat expression, on the other hand, activated histone-related genes. These regulatory shifts suggest a strategic reprogramming of host cellular states to favor viral replication, curbing protein synthesis and energy production to levels that support viral assembly but impair the host's immune defense and the production of immune-related proteins. Our findings provide a deeper understanding of the molecular changes associated with stable viral gene expression, which can inform the optimization of LVV production in gene therapy applications.
Heterozygous mutations in GNAO1 cause an ultra-rare neurodevelopmental disease called GNAO1 encephalopathy, characterized by infantile epilepsy and movement disorder. Here, we provide a functional characterization of the...Heterozygous mutations in GNAO1 cause an ultra-rare neurodevelopmental disease called GNAO1 encephalopathy, characterized by infantile epilepsy and movement disorder. Here, we provide a functional characterization of the hotspot mutation GNAO1 c.607G>A (p.G203R) and conduct early-phase development of an adeno-associated virus (AAV)-mediated gene therapy approach. The GNAO1 gene encodes the Gαo protein that is involved in neuronal signaling. We showed that the Gαo-G203R lost its ability to enhance forskolin-stimulated cAMP synthesis in HEK293T cells. In primary neuronal culture, Gαo-G203R had a dominant-negative effect on neuronal activity and GABA-dependent synaptic release. To ablate the mutant protein, we used selective silencing of the pathogenic variant using effectors of RNA interference (RNAi). We selected the short hairpin RNA (sh1500) that suppressed the c.607G>A transcripts, resulting in a 3.8-fold increase in the ratio of wild-type to mutant GNAO1 transcripts in patient-specific neurons. We also detected off-target effects of sh1500 as well as transcriptome changes associated with AAV transduction and RNAi activation. We improved the AAV construct by using an artificial miRNA (miR1500) and the neuron-specific hSyn promoter. Systemic administration of AAV9-hSyn-miR1500 did not cause pathological changes in Gnao1-GGA mice with a "humanized" target sequence. Importantly, AAV9 transduced Gαo-positive neurons in the striatum, thalamus, substantia nigra, and cerebellum, which we defined as primary targets for gene therapy. Our findings pave the road toward the development of AAV-RNAi approaches for dominant-negative GNAO1 variants.
Genetic engineering of microglial cells is a promising therapeutic avenue emerging with advancements in gene delivery techniques. Using a recently developed AAV capsid for efficient in vitro transduction we report the en...Genetic engineering of microglial cells is a promising therapeutic avenue emerging with advancements in gene delivery techniques. Using a recently developed AAV capsid for efficient in vitro transduction we report the engineering of microglia with CARs (CAR-Mic) targeting phagocytosis of amyloid beta 1‒42 (Aβ42). Functional screening of seven CAR constructs in human iPSC-derived microglia revealed up to 6-fold increases in internalized Aβ relative to viral control. CAR-driven phagocytic enhancement was selective for Aβ, dependent on intracellular domain signaling, and was confirmed in primary mouse microglia. These findings highlight the potential of using this approach to target dysfunctional microglia in Alzheimer's disease and other CNS disorders.