Gene Therapy Delivery Research Articles

New MiniPromoter Ple389 (ADORA2A) drives selective expression in medium spiny neurons in mice and non-human primates.

Compact cell type-specific promoters are important tools for basic and preclinical research and clinical delivery of gene therapy. In this work, we designed novel MiniPromoters to target D1 and D2 type dopaminoceptive medium spiny neurons in the striatum by manually identifying candidate regulatory regions or employing the OnTarget webserver. We then empirically tested the designs in rAAV-PHP.B for specificity and robustness in three systems: intravenous injection in mice, intracerebroventricular injection in mice, and intracerebroventricular injection in non-human primates. Twelve MiniPromoters were designed from eight genes: seven manually and five using OnTarget. When delivered intravenously in mice, three MiniPromoters demonstrated highly selective expression in the striatum, with Ple389 (ADORA2A) showing high levels of dopamine D2-receptor cell co-localization. The same three MiniPromoters also displayed enriched expression in the striatum when delivered intracerebroventricularly in mice with high levels of DARPP32 co-localization. Finally, Ple389 (ADORA2A) was intracerebroventricularly injected in non-human primates and showed enriched expression in the striatum as in the mouse. Ple389 (ADORA2A) demonstrated expression in the medium spiny neurons in all three systems tested and exhibited the highest level of D2-MSNs and DARPP32 co-labeling in mice, demonstrating its potential as a tool for gene therapy approaches for Parkinson and Huntington disease treatment.

Advancements in p53-Based Anti-Tumor Gene Therapy Research

The p53 gene is one of the genes most closely associated with human tumors and has become a popular target for tumor drug design. Currently, p53-based gene therapy techniques have been developed, but these therapies face challenges such as immaturity, high safety hazards, limited efficacy, and low patient acceptance. However, researchers are no less enthusiastic about the treatment because of its theoretical potential to treat cancer. In this paper, the advances in p53-based gene therapy and related nucleic acid delivery technologies were reviewed and prospected in order to support further development in this field.

Gene Therapy in Cardiovascular Disease: Recent Advances and Future Directions in Science: A Science Advisory From the American Heart Association.

Cardiovascular disease remains the foremost cause of morbidity and mortality globally, affecting millions of individuals. Recent discoveries illuminate the substantial role of genetics in cardiovascular disease pathogenesis, encompassing both monogenic and polygenic mechanisms and identifying tangible targets for gene therapies. Innovative strategies have emerged to rectify pathogenic variants that cause monogenic disorders such as hypertrophic, dilated, and arrhythmogenic cardiomyopathies and hypercholesterolemia. These include delivery of exogenous genes to supplement insufficient protein levels caused by pathogenic variants or genome editing to correct, delete, or modify mutant sequences to restore protein function. However, effective delivery of gene therapy to specified cells presents formidable challenges. Viral vectors, notably adeno-associated viruses and nonviral vectors such as lipid and engineered nanoparticles, offer distinct advantages and limitations. Additional risks and obstacles remain, including treatment durability, tissue-specific targeting, vector-associated adverse events, and off-target effects. Addressing these challenges is an ongoing imperative; several clinical gene therapy trials are underway, and many more first-in-human studies are anticipated. This science advisory reviews core concepts of gene therapy, key obstacles, patient risks, and ongoing research endeavors to enable clinicians to understand the complex landscape of this emerging therapy and its remarkable therapeutic potential to benefit cardiovascular disease.

Placental gene therapy in nonhuman primates: a pilot study of maternal, placental, and fetal response to non-viral, polymeric nanoparticle delivery of IGF1.

Currently, there are no placenta-targeted treatments to alter the in utero environment for administration to pregnant women who receive a diagnosis of fetal growth restriction (FGR). Water-soluble polymers have a distinguished record of clinical relevance outside of pregnancy. We have demonstrated the effective delivery of polymer-based nanoparticles containing a non-viral human insulin-like growth factor 1 (IGF1) transgene to correct placental insufficiency in small animal models of FGR. Our goals were to extend these studies to a proof-of-concept study in the pregnant macaque, establish feasibility of nanoparticle-mediated gene therapy delivery to trophoblasts, and investigate the acute maternal, placental, and fetal responses to treatment. Pregnant macaques underwent ultrasound-guided intraplacental injections of nanoparticles (GFP- or IGF1-expressing plasmid under the control of the trophoblast-specific PLAC1 promoter complexed with a HPMA-DMEAMA co-polymer) at approximately gestational day 100 (term = 165 days). Fetectomy was performed 24 h (GFP; n = 1), 48 h (IGF1; n = 3) or 10 days (IGF1; n = 3) after nanoparticle delivery. Routine pathological assessment was performed on biopsied maternal tissues and placental and fetal tissues. Maternal blood was analyzed for complete blood count (CBC), immunomodulatory proteins and growth factors, progesterone (P4), and estradiol (E2). Placental ERK/AKT/mTOR signaling was assessed using Western blot and qPCR. Fluorescent microscopy and in situ hybridization confirmed placental uptake and transient transgene expression in villous syncytiotrophoblast. No off-target expression was observed in either maternal or fetal tissues. Histopathological assessment of the placenta recorded observations not necessarily related to the IGF1 nanoparticle treatment. In maternal blood, CBCs, P4, and E2 remained within the normal range for pregnant macaques across the treatment period. Changes to placental ERK and AKT signaling at 48 h and 10 days after IGF1 nanoparticle treatment indicated an upregulation in placental homeostatic mechanisms to prevent overactivity in the normal pregnancy environment. The lack of adverse maternal reaction to nanoparticle-mediated IGF1 treatment, combined with changes in placental signaling to maintain homeostasis, indicates no deleterious impact of treatment during the acute phase of study.

Applications and Developments of Gene Therapy Drug Delivery Systems for Neurological Disorders

AbstractNeurological diseases (NDs) such as Alzheimer's disease, Parkinson's disease, ischemic strokes, spinal cord injuries, and other similar conditions that continue to pose a substantial health and economic burden on a global scale. It is crucial to tackle the difficulties provided by current medications due to the adverse effects and its immunological reactions to develop improved treatments for neurodegenerative illnesses. Gene therapy is currently being extensively used in preclinical and clinical studies for various diseases because of its ability to enhance the delivery and effectiveness of treatments. Various gene delivery techniques, including messenger RNA, small interfering RNA, antisense oligonucleotides, microRNA, CRISPR/Cas9 system, and plasmid DNA, have been created to address these difficulties. The goal of this study is to provide a clear overview of the pathophysiological underpinnings of NDs illnesses while also illuminating recent developments in gene delivery vector technologies. It goes over the main classifications of these vectors, their individual benefits and drawbacks, and their specific applications in the delivery of gene therapy.

Advances in glial cell line-derived neurotrophic factor

Glial cell line-derived neurotrophic factor (GDNF) is a potent neurotrophic factor with significant research value due to its profound effects on dopaminergic, cholinergic, and motor neurons. Initially identified for its neuroprotective role in dopaminergic neurons, GDNF has been found to support various neuronal populations and plays a crucial role in neural development, maintenance, and repair. This review provides a comprehensive overview of the molecular characteristics, tissue distribution, physiological function of GDNF and its protective effect on a series of diseases, emphasizing its potential therapeutic applications. Meanwhile, this study discusses the challenges in delivering GDNF across the blood-brain barrier and explores current strategies to enhance its clinical efficacy, including the use of gene therapy and innovative delivery methods. In summary, the review underscores the promise of GDNF as a therapeutic agent for neurodegenerative diseases and nerve injuries, highlighting the need for further research to translate these findings into clinical practice.

Identification of a novel neutralization epitope in rhesus AAVs

Adeno-associated viruses (AAVs) are popular gene therapy delivery vectors, but their application can be limited by anti-vector immunity. Both preexisting neutralizing antibodies (NAbs) and post-administration NAbs can limit transgene expression and reduce the clinical utility of AAVs. The development of novel AAVs will advance our understanding of AAV immunity and may also have practical applications. In this study, we identified five novel AAV capsids from rhesus macaques. RhAAV4282 exhibited 91.4% capsid sequence similarity with AAV7 and showed similar tissue tropism with slightly diminished overall signal. Despite this sequence homology, RhAAV4282 and AAV7 showed limited cross-neutralization. We determined a cryo-EM structure of the RhAAV4282 capsid at 2.57Å resolution and identified a small segment within the hypervariable region IV, involving seven amino acids that formed a shortened external loop in RhAAV4282 compared with AAV7. We generated RhAAV4282 and AAV7 mutants that involved swaps of this region and showed that this region partially determined neutralization phenotype. We termed thisregion the hypervariable region IV neutralizing epitope (HRNE). Our data suggests that modification of the HRNE can lead to AAVs with altered neutralization profiles.

Kidney-Targeting Mesoscale Nanoparticles for Delivery of Gene Therapy in CKD

Kidney-Targeting Mesoscale Nanoparticles for Delivery of Gene Therapy in CKD

Neuroimaging Applications for the Delivery and Monitoring of Gene Therapy for Central Nervous System Diseases.

Neurological disease due to single gene defects represents a targetable entity for adeno-associated virus (AAV) mediated gene therapy. The delivery of AAV-mediated gene therapy to the brain is challenging, owing to the presence of the blood-brain barrier. Techniques in gene transfer, such as convection-enhanced intraparenchymal delivery and image-guided delivery to the cerebrospinal fluid (CSF) spaces of the brain has led the field into highly accurate delivery techniques, which provide correction of genetic defects in specific brain regions or more broadly. These techniques commonly use magnetic resonance imaging (MRI), computed tomography (CT), and fluoroscopic guidance. Even more, the neuroimaging changes evaluated by MRI, MR spectroscopy (MRS), diffusion tensor imaging (DTI), and functional MRI (fMRI) can serve as important biomarkers of therapy effect and overall disease progression. Here, we discuss the role of neuroimaging in delivering AAV vectors and monitoring the effect of gene therapy.

Vesiclemania: ILGD INSTAND 2024 - A German extravaganza of tiny packages!

The 2024 IGLD INSTAND Symposium brought together leading experts in EV research. Key themes included the importance of methodological rigor and standardization, emphasized through the latest MISEV 2023 guidelines, and advances in EV isolation technologies. Several presentations explored the clinical applications of EVs, including their use in stem cell treatments, liquid biopsies, and as gene therapy delivery systems using EV-mediated CRISPR/Cas9. Discussions also focused on the interplay between EVs and the immune system, such as their role in modulating viral infections and their therapeutic potential in pathological situations and cancer. In conclusion, the event emphasized the need for inter-laboratory reproducibility and collaborative research to ensure EV technologies are primed for clinical translation, underscoring the importance of collaborative efforts to drive innovations in the field.

Nanodiamond: A Promising Carbon‐Based Nanomaterial for Therapeutic and Regenerative Dental Applications

AbstractNanodiamonds (NDs) are utilized for various purposes in dentistry, such as tissue regeneration, gene therapy, and medication delivery. Despite the examination of their potential for dental uses, there is currently no published review summarizing the conducted investigations. Additional investigations are required to comprehend the biological compatibility of NDs in dentistry. NDs have been proven effective for a variety of applications in dentistry because of unique qualities such as target cell selectivity, nanometer size, and fluorescence. Nanodiamonds find various applications in dentistry, encompassing roles in directed tissue regeneration, reinforcing polymers, and administering medications for treating infections and cancer. Researchers have also suggested the potential use of nanodiamonds as coatings for antibacterial or bioactive dental implants. Nevertheless, investigations on their biological compatibility have been scarce and insufficient so far, necessitating significantly further studies to envision the potential use of NDs in dentistry. It is believed that within the ten years to come, these emerging substances will discover several kinds of daily usage in dental practice.

Gene therapy for Duchenne Muscular Dystrophy: assessing the readiness of Italian centres of expertise.

Duchenne muscular dystrophy (DMD) is a heritable disorder that causes a rapid and progressive loss of ambulatory skills. There is no curative therapy for this pathology, that is currently managed with a combination of physiotherapy and pharmacological interventions limiting the progression of the disease (e.g. corticosteroids, cardiac medications). However, a new opportunity is represented by gene therapy, a promising treatment that, however, requires significant expertise during the whole delivery of care and a solid organisational infrastructure. An organisational strategy that could effectively support its delivery to DMD patients in Italy is the hub-and-spoke model. However, an accurate portrait of the present network of DMD centres of expertise in Italy and of their readiness in the delivery of gene therapy is paramount, to facilitate access to this experimental medicine in the future. In this context, the present study aimed to map the DMD centres of expertise in Italy and later evaluate their preparedness in terms of gene therapy delivery. For this purpose, a series of items was proposed to 30 centres in Italy, of which 20 responded. After assessing the readiness of the involved centres in terms of patient preparation, therapy infusion, close surveillance, and long-term follow-up, we proposed a suitable organizational model, namely a flexible hub-and-spoke model, for the delivery of gene therapy in the Italian DMD network and solutions to tackle the challenges emerged from the survey. Overall, the present study detected an adequate readiness of the Italian DMD centres of expertise, despite observing a significant room for improvement in digital infrastructures, culture, and training.

Nanoparticle-mediated delivery of placental gene therapy via uterine artery catheterization in a pregnant rhesus macaque

Nanoparticles offer promise as a mechanism to non-invasively deliver targeted placental therapeutics. Our previous studies utilizing intraplacental administration demonstrate efficient nanoparticle uptake into placental trophoblast cells and overexpression of human IGF1 (hIGF1). Nanoparticle-mediated placental overexpression of hIGF1 in small animal models of placental insufficiency and fetal growth restriction improved nutrient transport and restored fetal growth. The objective of this pilot study was to extend these studies to the pregnant nonhuman primate and develop a method for local delivery of nanoparticles to the placenta via maternal blood flow from the uterine artery. Nanoparticles containing hIGF1 plasmid driven by the placenta-specific PLAC1 promoter were delivered to a mid-gestation pregnant rhesus macaque via a catheterization approach that is clinically used for uterine artery embolization. Maternal-fetal interface, fetal and maternal tissues were collected four days post-treatment to evaluate the efficacy of hIGF1 treatment in the placenta. The uterine artery catheterization procedure and nanoparticle treatment was well tolerated by the dam and fetus through the four-day study period following catheterization. Nanoparticles were taken up by the placenta from maternal blood as plasmid-specific hIGF1 expression was detected in multiple regions of the placenta via in situ hybridization and qPCR. The uterine artery catheterization approach enabled successful delivery of nanoparticles to maternal circulation in close proximity to the placenta with no concerns to maternal or fetal health in this short-term feasibility study. In the future, this delivery approach can be used for preclinical evaluation of the long-term safety and efficacy of nanoparticle-mediated placental therapies in a rhesus macaque model.

Virus-like Particles for Disease Diagnosis and Drug Delivery Applications

Abstract: Virus-like particles (VLPs) are nanoscale, self-assembling cage structures made out of proteins with practical uses in biomedicine. They might be used to create better vaccinations, imaging equipment, gene and drug therapy delivery systems, and in vitro diagnostic equipment. VLPs are nanostructures that might be used in medicine, immunization, and diagnostics, among other areas. Many VLPs-based vaccines are now in use for the treatment of infectious diseases, and many more are on their way to clinical testing thanks to recent advancements in biomedical engineering. Although VLPs exhibit promising qualities in terms of efficacy, safety, and diversity, they may become more widely used in the future. Vaccines based on virus-like particles (VLPs) might serve as an effective addition to current immunization strategies for the prevention and treatment of emerging infectious diseases. The growing field of healthcare prevention has become increasingly interested in VLPs, leading to the discovery of various VLP-based candidate vaccines for vaccination towards a wide range of infectious pathogens, one of the most recent that has been developed is the vaccine against SARS-CoV-2, the effectiveness of that is now being tested. VLPs can elicit both antibody and cell-mediated immune responses, unlike standard inactivated viral vaccines. However, several problems persist with this surface display method and will need fixing in the future. VLPs-based medicinal delivery, nanoreactors for treatment, and imaging systems are being developed with promising results. The latest developments in the generation and fabrication of VLPs involve explorations of several expression systems for their creation and their application as vaccines for the avoidance of infectious diseases and malignancies. This manuscript offers the most advanced perspective on biomedical applications based on VLPs, as well as details innovative methods for manufacturing, functionalization, and delivery of VLPs.

Immunogenicity risk assessment of empty capsids present in adeno-associated viral vectors using predictive innate immune responses

Immunogenicity of gene therapy and the impacts on safety and efficacy are of increasing interest in the pharmaceutical industry. Unique structural aspects of gene therapy delivery vectors, such as adeno-associated viral (AAV) vectors, are expected to activate the innate immune system. The risk of innate immune activation is critical to understand due to the potential impacts on safety and on subsequent adaptive immune responses. In this study, we investigated the responses of key innate immune players—dendritic cells, natural killer (NK) cells, and the complement system—to AAV8 capsids. Immunogenicity risk was also predicted in the presence empty AAV capsids for AAV gene therapy. Compared to genome-containing "full" AAV8 capsids, empty AAV8 capsids more strongly induced proinflammatory cytokine production and migration by human and mouse dendritic cells, but the “full” capsid increased expression of co-stimulatory markers. Furthermore, in an NK cell degranulation assay, we found mixtures of empty and full AAV8 capsids to activate expression of TNF-α, IFN-γ, and CD107a more strongly in multiple NK cell populations compared to either capsid type alone. Serum complement C3a was also induced more strongly in the presence of mixed empty and full AAV8 capsid formulations. Risk for innate immune activation suggests the importance to determine acceptable limits of empty capsids. Immunogenicity risk assessment of novel biological modalities will benefit from the aforementioned in vitro innate immune activation assays providing valuable mechanistic information.

Oxidative Stress and Cataract Formation: Evaluating the Efficacy of Antioxidant Therapies.

This comprehensive review investigates the pivotal role of reactive oxygen species (ROS) in cataract formation and evaluates the potential of antioxidant therapies in mitigating this ocular condition. By elucidating the mechanisms of oxidative stress, the article examines how ROS contribute to the deterioration of lens proteins and lipids, leading to the characteristic aggregation, cross-linking, and light scattering observed in cataracts. The review provides a thorough assessment of various antioxidant strategies aimed at preventing and managing cataracts, such as dietary antioxidants (i.e., vitamins C and E, lutein, and zeaxanthin), as well as pharmacological agents with antioxidative properties. Furthermore, the article explores innovative therapeutic approaches, including gene therapy and nanotechnology-based delivery systems, designed to bolster antioxidant defenses in ocular tissues. Concluding with a critical analysis of current research, the review offers evidence-based recommendations for optimizing antioxidant therapies. The current literature on the use of antioxidant therapies to prevent cataract formation is sparse. There is a lack of evidence-based conclusions; further clinical studies are needed to endorse the use of antioxidant strategies in patients to prevent cataractogenesis. However, personalized treatment plans considering individual patient factors and disease stages can be applied. This article serves as a valuable resource, providing insights into the potential of antioxidants to alleviate the burden of cataracts.

Transforming Medicine with Nanobiotechnology: Nanocarriers and Their Biomedical Applications.

Nanobiotechnology, at the intersection of nanotechnology and biology, represents a burgeoning field poised to revolutionize medicine through the use of advanced nanocarriers. These nanocarriers, endowed with distinctive physiobiological attributes, are instrumental in diverse therapeutic domains including drug delivery for microbial infections, cancer treatment, tissue engineering, immunotherapy, and gene therapy. Despite the transformative potential, several challenges hinder their efficacy, such as limited drug capacity, suboptimal targeting, and poor solubility. This review delves into the latest advancements in nanocarrier technologies, examining their properties, associated limitations, and the innovative solutions developed to address these issues. It highlights promising nanocarrier systems like nanocomposites, micelles, hydrogels, microneedles, and artificial cells that employ advanced conjugation techniques, sustained and stimulus-responsive release mechanisms, and enhanced solubility. By exploring these novel structures and their contributions to overcoming existing barriers, the article emphasizes the vital role of interdisciplinary research in advancing nanobiotechnology. This field offers unparalleled opportunities for precise and effective therapeutic delivery, underscoring its potential to reshape healthcare through personalized, targeted treatments and improved drug performance.

Biodegradable silica nanoparticles for efficient linear DNA gene delivery

Targeting, safety, scalability, and storage stability of vectors are still challenges in the field of nucleic acid delivery for gene therapy. Silica-based nanoparticles have been widely studied as gene carriers, exhibiting key features such as biocompatibility, simplistic synthesis, and enabling easy surface modifications for targeting. However, the ability of the formulation to incorporate DNA is limited, which restricts the number of DNA molecules that can be incorporated into the particle, thereby reducing gene expression. Here we use polymerase chain reaction (PCR)-generated linear DNA molecules to augment the coding sequences of gene-carrying nanoparticles, thereby maximizing nucleic acid loading and minimizing the size of these nanocarriers. This approach results in a remarkable 16-fold increase in protein expression six days post-transfection in cells transfected with particles carrying the linear DNA compared with particles bearing circular plasmid DNA. The study also showed that the use of linear DNA entrapped in DNA@SiO2 resulted in a much more efficient level of gene expression compared to standard transfection reagents. The system developed in this study features simplicity, scalability, and increased transfection efficiency and gene expression over existing approaches, enabled by improved embedment capabilities for linear DNA, compared to conventional methods such as lipids or polymers, which generally show greater transfection efficiency with plasmid DNA. Therefore, this novel methodology can find applications not only in gene therapy but also in research settings for high-throughput gene expression screenings.

Abstract We105: cBIN1 Gene Therapy Improves Left Ventricular Filling Pressure in a Canine Model of Ischemic Dilated Cardiomyopathy

Introduction: In heart failure patients, increased left ventricular end diastolic pressure (LVEDP) is pathognomonic of myocardial dysfunction. Previously, we presented that gene therapy with exogeneous cardiac bridging integrator 1 (cBIN1), a membrane scaffolding protein that organizes T-tubule microdomains and is decreased in failing hearts, recovers systolic function in a canine model of chronic ischemic dilated cardiomyopathy (IDCM). The effect of catheter-based delivery of cBIN1 gene therapy on increased LVEDP is unclear. Hypothesis: We tested the hypothesis that cBIN1 gene therapy improves LVEDP in a canine model of IDCM. Methods: Twelve healthy dogs (30±2 kg) underwent left anterior descending artery ligation and developed IDCM with LVEF <40% and NT-proBNP >900 pmol/L over 3–4 months. Animals received a single application at 20 subendocardial LV sites of either AAV9-GFP (control, n=6) or AAV9-cBIN1 (n=6) using a MyoStar catheter-based injection. Pressure-volume loops were acquired in vivo, including measurement of LVEDP, end-systolic pressure-volume relation (ESPVR), isovolumic relaxation time (IVRT) and isovolumetric contraction time (IVCT). Measurements were performed on the day prior to administering the therapy ( pre-therapy ) and 5–8 weeks post-intramyocardial injection ( post-therapy ). For statistics, student t-test was used, and p<0.05 refers as significant. Results are reported as mean±SD. Results: In AAV9-GFP control-treated dogs, compared with pre-therapy, post-therapy LVEDP elevated significantly (13±1 vs. 17±1 mmHg, p=0.002, Figure A ), whereas in the cBIN1-treated cohort, elevated LVEDP improved significantly (13±4 vs. 11±3 mmHg, p=0.042). With control therapy, ESPVR exhibited a significant decrease in contractility (1.40±0.44 vs. 1.81±0.49 mmHg/mL, p=0.001, Figure B ), whereas cBIN1 therapy caused a substantial improvement in ESPVR (1.54±0.71 vs. 1.34±0.43 mmHg/mL, p=0.022, Figure B ). At the post-therapy time-point, compared with control therapy, cBIN1 therapy improved IVRT (96±10 vs. 72±8 ms, p<0.001, Figure C ) and IVCT (49±4 vs. 40±3 ms, p=0.009, Figure D ). Conclusion: cBIN1 gene therapy reduces elevated LV filling pressure and improves overall hemodynamics in a canine model of chronic IDCM.

Innovative approaches in characterizing and developing methods for lipoidal vesicular drug delivery systems

Lipoidal vesicular systems, including liposomes, ethosomes, and transferosomes, represent a significant advancement in targeted drug delivery, offering enhanced bioavailability, controlled release, and specific targeting capabilities. This review discusses the types of lipoidal vesicular systems, their methods of characterization, method development, applications, advantages, challenges, and future perspectives. These systems have shown immense potential in diverse therapeutic areas, including cancer therapy, infectious diseases, gene therapy, and transdermal drug delivery. Despite the challenges in stability, scalability, and targeting, ongoing research and technological advancements promise to expand their applications and improve therapeutic outcomes.