Search Results (341)

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

Background: Fabry disease (FD) is an X-linked lysosomal storage disorder caused by mutations in the GLA gene, resulting in α-galactosidase A (α-Gal A) deficiency and progressive accumulation of globotriaosylceramide (Gb3). Current therapies, such as enzyme replacement and chaperone therapy, have limitations, including incomplete biodistribution and mutation-specific efficacy. Gene therapy using adeno-associated virus (AAV) vectors presents a promising alternative. Methods: In this study, we assessed the dose-dependent effects of AAV8 and AAV9 vectors encoding human GLA in Gla knockout (Gla^−/y) mice by measuring α-Gal A activity and monitoring safety. To evaluate therapeutic efficacy, symptomatic Fabry mice (G3S^Tg/+Gla^−/y) were used. Results: AAV9-GLA produced significantly higher and more sustained enzyme activity than AAV8-GLA across plasma, liver, heart, and kidney. In symptomatic mice, AAV9-GLA achieved superior reductions in serum Gb3 and lyso-Gb3 levels, greater Gb3 clearance in heart and kidney tissues, and improved proteinuria. Anti-GLA IgG titers remained below threshold for the first four weeks and increased modestly by week eight, indicating a limited humoral immune response. No significant clinical signs or weight loss were observed in Gla^−/y mice over the 3.5-month study period, supporting the favorable safety profile of AAV-mediated gene therapy. Conclusions: These findings demonstrate that AAV9 provides enhanced biodistribution and therapeutic efficacy compared to AAV8, supporting its potential for the treatment of Fabry disease. Full article

Adeno-associated virus (AAV) vectors have emerged as the leading platform for retinal gene therapy due to their favorable safety profile, low immunogenicity, and ability to mediate long-term transgene expression within the immune-privileged ocular environment. By integrating diverse strategies such as gene augmentation and gene editing, AAV-based therapies have demonstrated considerable promise in treating both inherited and acquired retinal disorders. However, their clinical translation remains limited by several key challenges, including restricted packaging capacity, suboptimal transduction efficiency, the risk of gene therapy-associated uveitis, and broader societal concerns such as disease burden and ethical oversight. This review summarizes recent advances aimed at overcoming these barriers, with a particular focus on delivery route-specific disease applicability, multi-vector systems, and capsid engineering approaches to enhance payload capacity, targeting specificity, and biosafety. By synthesizing these developments, we propose a conceptual and technical framework for a more efficient, safer, and broadly applicable AAV platform to accelerate clinical adoption in retinal gene therapy. Full article

Gene therapy for hemophilia B offers the advantage of a single administration with sustained therapeutic effects. This study evaluated the systemic safety, efficacy, biodistribution, and immunogenicity of AAV8-FIX-TripleL, a recombinant adeno-associated virus type 8 (AAV8) vector encoding a modified factor IX (FIX) variant with increased activity. In this good laboratory practice (GLP)-compliant study, 180 male FIX-knockout hemophilia B mice were randomized into 12 groups (n = 15) and received intravenous AAV8-FIX-TripleL at therapeutic (5 × 10¹¹ VG/kg) or supraphysiological (5 × 10¹² VG/kg) doses on Day 1. The mice were sacrificed on Days 2, 15, 28, and 91 for comprehensive evaluations, including hematological and biochemical assessments, histopathological examination, FIX protein/activity analysis, immunogenicity assessment, and vector biodistribution via quantitative polymerase chain reaction (qPCR) in major organs. AAV8-FIX-TripleL demonstrated dose-dependent increases in FIX activity and protein levels, with FIX activity exceeding physiological levels and the maintenance of a favorable safety profile. Biodistribution analysis confirmed predominant hepatic accumulation and vector persistence up to 91 days post-injection, with minimal off-target distribution. These findings indicate that AAV8-FIX-TripleL is a promising gene therapy candidate for hemophilia B, as it has robust expression, sustained efficacy, and a favorable safety profile, and that further translational studies are warranted. Full article

Dry age-related macular degeneration (AMD) is a leading cause of vision loss in individuals over 50, yet no approved therapies exist for early or intermediate stages of the disease. Oxidative stress is a central driver of retinal degeneration in AMD, and sodium iodate (NaIO₃)-induced injury serves as a well-characterized model of oxidative damage to the retinal pigment epithelium (RPE) and photoreceptors. BMI1, a poly-comb group protein involved in DNA repair, mitochondrial function, and cellular renewal, has emerged as a promising therapeutic target for retinal neuroprotection. We evaluated the efficacy of AAV-mediated BMI1 gene delivery in murine models using two administration routes: subretinal (SR) and suprachoroidal (SC). AAV5.BMI1 (1 × 10⁹ vg/eye) was delivered SR in Balb/c mice and evaluated at 4 and 15 weeks post-injection. AAV8.BMI1 (5 × 10⁹ or 1 × 10¹⁰ vg/eye) was administered SC in C57BL/6 mice and assessed at 4 weeks. Control groups received BSS or AAV8.stuffer. Following NaIO₃ exposure, retinal structure and function were analyzed by optical coherence tomography (OCT), electroretinography (ERG), histology, and molecular assays. SC delivery of AAV8.BMI1 achieved the highest levels of retinal BMI1 expression with no evidence of local or systemic toxicity. Treated eyes showed dose-dependent preservation of outer nuclear layer (ONL) thickness and significantly improved ERG responses indicating structural and functional protection. These findings support SC AAV.BMI1 gene therapy as a promising, minimally invasive, and translatable approach for early intervention in intermediate AMD. Full article

Neutralizing antibodies (nAbs) are an important component of the immune system, which plays a dual role in modern medicine. On the one hand, they significantly limit the effectiveness of gene therapy based on viral vectors, reducing the effectiveness of treatment of diseases such as spinal muscular atrophy, which is especially evident with repeated administration of therapeutic vectors. On the other hand, nAbs is a promising tool for combating viral infections. This review systematizes current data on the mechanisms of nAbs formation against AAV vectors, analyzes the factors influencing their production, and discusses strategies to overcome this limitation, including modification of vectors and the development of methods to suppress the immune response. Special attention is paid to the prospects of using nAbs as therapeutic agents against viral infections. The key problems and possible directions of research development in this area are considered, which is important for improving approaches to the treatment of both rare genetic and infectious diseases. Full article