Search Results (346)

The IQSEC2 protein is a guanine nucleotide exchange factor for Arf6. Pathogenic variants in the X-linked IQSEC2 gene are associated with drug-resistant epilepsy, severe intellectual disability, and autism. The vast majority of disease-causing variants introduce premature termination codons into the IQSEC2 gene, resulting in little or no IQSEC2 protein being produced. Approximately 20% of cases are missense variants in the seven functional domains of the IQSEC2 protein. We sought to determine whether an adeno-associated virus (AAV) containing the IQSEC2 gene could rescue abnormal phenotypes in mice in two different Iqsec2 mouse models with premature Iqsec2 termination codons resulting in a knockout of the Iqsec2 gene expression and in mice with an A350V Iqsec2 missense mutation. In the Iqsec2 knockout mice, the AAV significantly improved growth, corrected behavioral abnormalities, and normalized the seizure threshold. Behavioral abnormalities were partially rescued in A350V mice, which expression studies suggest may have been due to the feedback inhibition of the endogenous Iqsec2 allele by viral IQSEC2. We propose that the success in the Iqsec2 knockout mice warrants a proof-of-concept study for gene replacement therapy in boys with IQSEC2 premature termination variants. Full article

Currently, the development of adeno-associated virus (AAV)-based gene therapy is a promising method for treating various diseases and is gaining increasing popularity. However, the use of AAV has certain drawbacks and faces limitations such as immune responses and an increased risk of insertional mutagenesis, which have not always been adequately considered in the context of AAV therapy. Moreover, a significant limitation for the application of AAV lies in the challenge of producing it in large quantities. This article discusses the use of AAV in treating various diseases, reviews AAV production approaches, highlights challenges with insufficient viral titers during production, and explores potential solutions at key stages of AAV drug production. Full article

Rett syndrome is a severe neurodevelopmental disorder that occurs primarily in females and is caused by mutations in the methyl-CpG-binding protein 2 (MECP2) gene located on the X chromosome. Though MECP2 acts as a representative transcriptional regulator and affects gene expression both directly and indirectly, a complete understanding of this disease and the treatment mechanism has not been established yet. MECP2 plays a particularly important role in synaptic development, neuronal maturation, and epigenetic regulation in the brain. In this study, we summarize the molecular structure of MECP2, mutation-specific pathogenesis, and the role of MECP2 in regulating chromatin remodeling, RNA splicing, and miRNA processing to provide a comprehensive understanding of Rett syndrome. Additionally, we describe abnormal phenotypes manifested in various brain regions and other tissues owing to MECP2 dysfunction. Finally, we discuss current and future therapeutic approaches, including AAV-based gene therapy, RNA editing, X chromosome reactivation, and pharmacological interventions. Understanding the diverse functions and pathological mechanisms of MECP2 provides an important foundation for developing targeted therapies for Rett syndrome. Full article

Maturity-onset diabetes of the young type 10 (MODY10) is a monogenic diabetes subtype caused by heterozygous mutations in the insulin gene (INS), leading to defective proinsulin processing, endoplasmic reticulum (ER) stress, and β-cell dysfunction. Current management relies on sulfonylureas or insulin therapy, but these fail to address the underlying genetic defect. Recent research has elucidated the molecular mechanisms of MODY10, including ER stress induced by proinsulin misfolding, activation of the unfolded protein response (UPR), and β-cell apoptosis. Emerging therapies such as Adeno-Associated Virus (AAV)-mediated gene delivery to induce the glucose-responsive hepatic insulin expression, plasmid-based single-chain insulin analogs, and cell-based therapies show promise in preclinical studies. However, critical challenges remain, including immune responses to AAV vectors, incomplete correction of dominant-negative mutant effects, and the need for long-term safety data. This review summarizes current knowledge on MODY10 genetics, pathophysiology, and therapeutic innovations, while identifying key gaps for future research to enable precision medicine approaches. Full article

Myopia is one of the major public health conditions with significant complications. This study investigates the role of transforming growth factor (TGF)-β2, complement activation, and inflammasome pathways in myopia progression using a Brown Norway rat model. Myopia was induced, and complement regulation was manipulated using gene therapy via adeno-associated virus (AAV) vectors delivering CD55 or CD55 siRNA. Results showed that TGF-β2 exacerbated myopia by upregulating complement components C3 and C5, suppressing CD55, and activating inflammasome pathways through nuclear factor (NF)-κB signaling, leading to axial elongation and increased refractive errors. Overexpression of CD55 via AAV gene therapy effectively counteracted these effects, reducing axial length elongation and inflammation by suppressing inflammasome markers interleukin (IL)-1β and NLR family pyrin domain containing 3 (NLRP3), as confirmed by real-time quantitative PCR and immunofluorescence analyses. Conversely, silencing CD55 intensified TGF-β2-induced effects, further promoting axial elongation and inflammation. These findings highlight the critical role of CD55 in modulating TGF-β2-driven complement and inflammasome activation during myopia progression. The study suggests that gene therapy targeting CD55 could serve as a novel therapeutic strategy to mitigate myopia and related inflammatory processes, offering a promising avenue for managing this significant public health challenge. Full article

Myopathies and muscular dystrophies are a diverse group of rare or ultra-rare diseases that significantly impact patients’ quality of life and pose major challenges for diagnosis and treatment. Despite their heterogeneity, many share common molecular mechanisms, particularly involving sarcomeric dysfunction, impaired autophagy, and disrupted gene expression. This review explores the genetic and pathophysiological foundations of major myopathy subtypes, including cardiomyopathies, metabolic and mitochondrial myopathies, congenital and distal myopathies, myofibrillar myopathies, inflammatory myopathies, and muscular dystrophies. Special emphasis is placed on the role of autophagy dysregulation in disease progression, as well as its therapeutic potential. We discuss emerging diagnostic approaches, such as whole-exome sequencing, advanced imaging, and muscle biopsy, alongside therapeutic strategies, including physiotherapy, supplementation, autophagy modulators, and gene therapies. Gene therapy methods, such as adeno-associated virus (AAV) vectors, CRISPR-Cas9, and antisense oligonucleotide, are evaluated for their promise and limitations. The review also highlights the potential of drug repurposing and artificial intelligence tools in advancing diagnostics and personalized treatment. By identifying shared molecular targets, particularly in autophagy and proteostasis networks, we propose unified therapeutic strategies across multiple myopathy subtypes. Finally, we discuss international research collaborations and rare disease programs that are driving innovation in this evolving field. Full article

Skeletal muscle, constituting ~40% of body mass, serves as a primary effector for movement and a key metabolic regulator through myokine secretion. Hereditary myopathies, including dystrophinopathies (DMD/BMD), limb–girdle muscular dystrophies (LGMD), and metabolic disorders like Pompe disease, arise from pathogenic mutations in structural, metabolic, or ion channel genes, leading to progressive weakness and multi-organ dysfunction. Gene therapy has emerged as a transformative strategy, leveraging viral and non-viral vectors to deliver therapeutic nucleic acids. Adeno-associated virus (AAV) vectors dominate clinical applications due to their efficient transduction of post-mitotic myofibers and sustained transgene expression. Innovations in AAV engineering, such as capsid modification (chemical conjugation, rational design, directed evolution), self-complementary genomes, and tissue-specific promoters (e.g., MHCK7), enhance muscle tropism while mitigating immunogenicity and off-target effects. Non-viral vectors (liposomes, polymers, exosomes) offer advantages in cargo capacity (delivering full-length dystrophin), biocompatibility, and scalable production but face challenges in transduction efficiency and endosomal escape. Clinically, AAV-based therapies (e.g., Elevidys^® for DMD, Zolgensma^® for SMA) demonstrate functional improvements, though immune responses and hepatotoxicity remain concerns. Future directions focus on AI-driven vector design, hybrid systems (AAV–exosomes), and standardized manufacturing to achieve “single-dose, lifelong cure” paradigms for muscular disorders. Full article

Retinitis pigmentosa is a group of inherited retinal dystrophies characterized by progressive photoreceptor cell loss leading to irreversible vision loss. Affecting approximately 1 in 4000 individuals worldwide, retinitis pigmentosa exhibits significant genetic heterogeneity, with mutations in genes such as RHO, PRPF31, RPE65, USH2A, and NR2E3, which contribute to its diverse clinical presentation. This review outlines the genetic basis of retinitis pigmentosa and explores cutting-edge gene-based therapeutic strategies. Luxturna (voretigene neparvovec-rzyl), the first FDA-approved gene therapy targeting RPE65 mutations, represents a milestone in precision ophthalmology, while OCU400 is a gene-independent therapy that uses a modified NR2E3 construct to modulate retinal homeostasis across different RP genotypes. Additionally, CRISPR–Cas genome-editing technologies offer future potential for the personalized correction of specific mutations, though concerns about off-target effects and delivery challenges remain. The article also highlights MCO-010, a novel optogenetic therapy that bypasses defective phototransduction pathways, showing promise for patients regardless of their genetic profile. Moreover, QR-1123, a mutation-specific antisense oligonucleotide targeting the P23H variant in the RHO gene, is under clinical investigation for autosomal dominant RP and has shown encouraging preclinical results in reducing toxic protein accumulation and preserving photoreceptors. SPVN06, another promising candidate, is a mutation-agnostic gene therapy delivering RdCVF and RdCVFL via AAV to support cone viability and delay degeneration, currently being evaluated in a multicenter Phase I/II trial for patients with various rod–cone dystrophies. Collectively, these advances illustrate the transition from symptom management toward targeted, mutation-specific therapies, marking a major advancement in the treatment of RP and inherited retinal diseases. Full article

Gene replacement using adeno-associated viral (AAV) vectors has become a major therapeutic avenue for neurodegenerative diseases (NDD). In single-gene diseases with loss-of-function mutations, the objective of gene therapy is to express therapeutic transgenes abundantly in cell populations that are implicated in the pathological phenotype. X-ALD is one of these orphan diseases. It is caused by ABCD1 gene mutations and its main clinical form is adreno-myelo-neuropathy (AMN), a disabling spinal cord axonopathy starting in middle-aged adults. Unfortunately, the main cell types involved are yet poorly identified, complicating the choice of cells to be targeted by AAV vectors. Pioneering gene therapy studies were performed in the Abcd1^-/y mouse model of AMN with AAV9 capsids carrying the ABCD1 gene. These studies tested ubiquitous or cell-specific promoters, various routes of vector injection, and different ages at intervention to either prevent or reverse the disease. The expression of one of these vectors was studied in the spinal cord of a healthy primate. In summary, gene therapy has made promising progress in the Abcd1^-/y mouse model, inaugurating gene replacement strategies in AMN patients. Because X-ALD is screened neonatally in a growing number of countries, gene therapy might be applied in the future to patients before they become overtly symptomatic. Full article

Cardiovascular disease encompasses a wide group of conditions that affect the heart and blood vessels. Of these diseases, cardiomyopathies and arrhythmias specifically have been well-studied in their relationship to cardiac dyads, nanoscopic structures that connect electrical signals to muscle contraction. The proper development and positioning of dyads is essential in excitation–contraction (EC) coupling and, thus, beating of the heart. Three proteins, namely CMYA5, JPH2, and BIN1, are responsible for maintaining the dyadic cleft between the T-tubule and junctional sarcoplasmic reticulum (jSR). Various other dyadic proteins play integral roles in the primary function of the dyad—translating a propagating action potential (AP) into a myocardial contraction. Ca²⁺, a secondary messenger in this process, acts as an allosteric activator of the sarcomere, and its cytoplasmic concentration is regulated by the dyad. Loss-of-function mutations have been shown to result in cardiomyopathies and arrhythmias. Adeno-associated virus (AAV) gene therapy with dyad components can rescue dyadic dysfunction, which results in cardiomyopathies and arrhythmias. Overall, the dyad and its components serve as essential mediators of calcium homeostasis and excitation–contraction coupling in the mammalian heart and, when dysfunctional, result in significant cardiac dysfunction, arrhythmias, morbidity, and mortality. Full article

Atherosclerosis is a complex disease characterized by pathological thickening of the arterial intima. The mechanisms underlying the induction and progression of atherosclerosis are convoluted and remain under active investigation, with key components such as lipid accumulation and local inflammation being identified. Several risk factors (e.g., metabolic disorders, genetic background, diet, infections) have been shown to exacerbate disease progression, but their roles as clinically relevant markers remain to be established. Despite the growing body of evidence on the molecular pathogenesis of atherosclerosis, there is no effective preventive treatment against the development of this disease. In this review, we focus on gene targets for gene therapy as a novel potential approach to cure and prevent atherosclerosis. We critically review recent research demonstrating the therapeutic potential of viral vector-based (adeno-associated virus (AAV) and lentivirus) gene therapy for the treatment of atherosclerosis. We also summarize alternative gene targets and approaches (e.g., non-coding RNA (ncRNA), micro RNA (miRNA), small interfering RNA (siRNA), antisense oligonucleotide (ASO), CRISPR/Cas9) that aim to limit disease progression. We highlight the importance of local inflammation in the pathogenesis of atherosclerosis and propose gene targets with anti-inflammatory activity to inhibit the pathological inflammatory response. In addition, we provide perspectives on the future development of gene therapeutics and their potential applications. We anticipate that recent advances in gene therapy will help to identify new and effective targets to prevent atherosclerosis. Full article

Adeno-associated virus (AAV) vectors have emerged as powerful tools for in vivo gene therapy, enabling long-term transgene expression in targeted tissues with minimal pathogenicity. This review examines the AAV serotypes used in clinical gene therapy trials for neurodegenerative (central nervous system, CNS) diseases, highlighting their tropisms, engineering advances, and translational progress. We discuss how capsid modifications, cell-specific promoters, and novel delivery routes are enhancing AAV tropism and reducing immunogenicity to overcome current limitations. Key clinical trials in neurodegenerative disorders (such as Parkinson’s, Alzheimer’s, and Huntington’s disease) are summarized, including delivery methods (intravenous, intracoronary, intrathecal, etc.) and outcomes. We further outline the regulatory landscape with recent approvals of AAV-based therapies and ongoing efforts to address safety challenges like immune responses and vector dose toxicity. A more translational, forward-looking perspective is adopted to consider combination therapies (e.g., AAV with immune modulation or genome editing) and strategic directions to improve the next generation of AAV vectors. Overall, continued innovation in AAV vector design and delivery, alongside careful clinical evaluation, is accelerating the translation of gene therapies for neurodegenerative diseases. Full article

Adeno-associated virus (AAV) vectors face a critical translational challenge in ocular gene therapy due to pre-existing neutralizing antibodies (NAbs) whose seroprevalence limits patient eligibility. Standard NAb detection using non-ocular cell models (Human Embryonic Kidney 293T) may inadequately predict retinal transduction inhibition due to cell type-related variations in receptor usage and immunogenicity. This study established parallel NAb detection platforms utilizing human retinal pigment epithelial (ARPE-19) cells and standard 293T cells to systematically evaluate clinical serum samples against ophthalmologically relevant AAV serotypes (2, 5, 8, 9) via luciferase reporter-based transduction inhibition assays. Comparative analysis demonstrated ARPE-19 exhibited 42–48% higher NAb titers against AAV5/9 compared to 293T cells, with distinct serotype-biased neutralization hierarchies observed between cellular models. Furthermore, female-derived sera exhibited significantly elevated NAbs against particular serotypes in the ARPE-19 system. Critically, inter-serotype cross-neutralization correlation patterns differed substantially between cellular platforms. These findings demonstrate that physiologically relevant retinal cellular models provide essential immunological profiling data, revealing NAb characteristics obscured in standard assays. Consequently, employing retinal cell-based platforms is crucial for optimizing AAV serotype selection, patient stratification, and predicting clinical outcomes in ocular gene therapy. Full article

Recombinant adeno-associated virus (rAAV) is the leading vector for gene replacement therapy; however, the roles and regulation of host proteins in rAAV production remain incompletely understood. In this comparative proteomic analysis, we focused on proteins in the nucleus, the epicenter of DNA uptake, transcription, capsid assembly, and packaging. HEK-293 cells were analyzed under the following three conditions: (i) untransfected, (ii) mock-transfected with the ITR and an unrelated plasmid, and (iii) triple-transfected with rAAV2 production plasmids. Cells were harvested at 24 and 72 h post-transfection, and nuclear fractions were processed using filter-aided sample preparation (FASP) followed by nano-scale liquid chromatography–tandem mass spectrometry (nLC-Orbitrap MS/MS). Across all samples, we identified 3384 proteins, revealing significant regulatory changes associated with transfection and rAAV production. Transfection alone accounted for some of the most substantial proteomic shifts, while rAAV production induced diverse regulatory changes linked to cell cycle control, structure, and metabolism. STRING analysis of significantly regulated proteins also identified an enrichment of those associated with the Gene Ontology (GO) term ‘response to virus’. Additionally, we examined proteins with reported relation to adenoviral components. Our findings help to unravel the complexity of rAAV production, identify interesting targets for further investigation, and may contribute to improving rAAV yield. Full article