Abstract 543: Clinical Development of Cardiac Reprogramming Gene Therapy

2020 ◽  
Vol 127 (Suppl_1) ◽  
Author(s):  
Huanyu Zhou ◽  
Laura M Lombardi ◽  
Christopher A Reid ◽  
Jin Yang ◽  
Chetan Srinath ◽  
...  
Keyword(s):  
Heart Failure ◽  
Gene Therapy ◽  
Clinical Application ◽  
Cardiac Fibroblasts ◽  
Target Cells ◽  
Large Animal ◽  
Safety And Efficacy ◽  
Treat Heart Failure ◽  
Ability To Regenerate

Heart failure affects an estimated 38 million people worldwide and is typically caused by cardiomyocyte (CM) loss or dysfunction. Although CMs have limited ability to regenerate, a large pool of non-myocytes, including cardiac fibroblasts (CFs), exist in the postnatal heart. In vivo reprogramming of non-myocytes into functional CMs is emerging as a potential new approach to treat heart failure and substantial proof-of-concept has been achieved in this new field. However, challenges remain in terms of clinical application. First, reported human reprogramming cocktails often consist of five to seven factors that require multiple AAV vectors for delivery. Thus, a less complex cocktail that is able to fit into one AAV vector is needed for this technology to impact human health. Second, the lack of specificity in AAV tropism further complicates the safety and regulatory landscape. A means to limit the expression of reprogramming factors to target cells is critical for maximizing long-term safety. Lastly, although promising studies in small animals have already been reported, safety and efficacy results in large animal MI models are critical to justify cardiac reprogramming in human clinical trials. We have developed a novel human cardiac reprogramming cocktail that consists of only two transcription factors and one miRNA. This new cocktail has been engineered into a single AAV cassette to efficiently reprogram human CFs into cardiomyocytes. We also substantially improved transduction of hCFs through AAV capsid engineering and eliminated CMs expression through a microRNA de-targeting method. Moreover, our novel cardiac reprogramming gene therapy improved cardiac function in both rat and swine MI models upon delivery at various time-points after MI without inducing arrhythmias. Given these promising safety and efficacy results in larger animals, we endeavor to translate direct cardiac reprogramming for clinical application.

Abstract 16635: Enhanced Cardiac Delivery of a Small Soluble Antifibrotic Peptide With Liposomal Encapsulation

Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Swati D Sonkawade ◽  
Shirley Xu ◽  
Saraswati Pokharel ◽  
Umesh C Sharma
Keyword(s):  
Membrane Trafficking ◽  
Cardiac Fibrosis ◽  
Cardiac Fibroblasts ◽  
Target Cells ◽  
Large Animal ◽  
Inhibitory Peptide ◽  
Free Peptide ◽  
Large Animal Models ◽  
Distribution Studies

Introduction: N-acetyl-ser-asp-lys-pro (Ac-SDKP) is an enodogenous anti-fibrotic peptide with a great potential for use as a “ replacement therapy ” in fibrotic myocardial remodeling. However, its therapeutic use is limited by its short half-life (4.5 mins) and a negligible bioavailibity. Hypothesis: We hypothesize that liposomal encapsulation of Ac-SDKP (L-Ac-SDKP) enhances its stability, and improves delivery into the myocardial target cells at a higher efficiency than free Ac-SDKP. This will maximize retention time, allowing intermittent dosing and minimizing off-target effects. Methods: We synthesized L-Ac-SDKP using zwitterionic lipid formulation for better cell membrane penetration. We used Fluorophore (FITC)-conjugated Ac-SDKP as a tracer, and scrambled peptides and blank liposomes as controls. After confirming an enhanced uptake efficiency of L-Ac-SDKP into the adult cardiac fibroblasts, we performed in vivo L-Ac-SDKP uptake and distribution studies in a model of cardiac fibrosis induced by 30Gy of thoracic ionizing radiation exposure. Results: Confocal microscopy of the cultured cardiac fibroblasts showed L-Ac-SDKP distribution localized to perinuclear areas corroborating its known effects on cell-cycle and nuclear membrane trafficking compared to the free peptide. Along with flow cytometry analysis L-Ac-SDKP uptake was seen in 98% of cells as opposed to 7% when treated with free Ac-SDKP. In vivo, the mouse model of myocardial fibrosis showed significantly increased L-Ac-SDKP uptake (33±3 fold), compared to normal controls (14±3 fold) after 5 daily injections. Quantification of Ac-SDKP in the cardiac homogenate reached a maximum therapeutic concentration of 1.4 pg/mg after 2 doses in irradiated mice, whereas even higher concentration could be achieved after 5 cumulative doses. Conclusion: We conclude that liposomal-conjugation is a highly effective therapeutic approach for targeting cardiac fibrosis using a potent fibroblast inhibitory peptide, Ac-SDKP as a therapeutic agent. Translational studies in large animal models are currently in progress for further testing its therapeutic utility.

Non-Viral Vectors for Gene Delivery

2018 ◽  
Vol 9 (1) ◽  
pp. 4-11 ◽  
Author(s):  
Aparna Bansal ◽  
Himanshu
Keyword(s):  
Gene Therapy ◽  
Viral Vectors ◽  
Transfection Efficiency ◽  
Gene Transfection ◽  
Expression System ◽  
Target Cells ◽  
Specific Expression ◽  
Naked Dna

Introduction: Gene therapy has emerged out as a promising therapeutic pave for the treatment of genetic and acquired diseases. Gene transfection into target cells using naked DNA is a simple and safe approach which has been further improved by combining vectors or gene carriers. Both viral and non-viral approaches have achieved a milestone to establish this technique, but non-viral approaches have attained a significant attention because of their favourable properties like less immunotoxicity and biosafety, easy to produce with versatile surface modifications, etc. Literature is rich in evidences which revealed that undoubtedly, non–viral vectors have acquired a unique place in gene therapy but still there are number of challenges which are to be overcome to increase their effectiveness and prove them ideal gene vectors. Conclusion: To date, tissue specific expression, long lasting gene expression system, enhanced gene transfection efficiency has been achieved with improvement in delivery methods using non-viral vectors. This review mainly summarizes the various physical and chemical methods for gene transfer in vitro and in vivo.

Abstract 2883: Retroinfusion-facilitated Inotropic AAV9-S100A1 Gene Therapy Restores Global Cardiac Function In A Clinically Relevant Pig Heart Failure Model

Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Sven T Pleger ◽  
Changguang Shan ◽  
Jan Kziencek ◽  
Oliver Mueller ◽  
Raffi Bekeredjian ◽  
...  
Keyword(s):  
Heart Failure ◽  
Gene Therapy ◽  
Gene Transfer ◽  
Cardiac Function ◽  
Left Ventricular ◽  
Large Animal ◽  
Circumflex Artery ◽  
Cell Counts ◽  
Clinical Conditions

Background: Cardiac expression of the Ca-dependent inotropic protein S100A1 is decreased in human end-stage heart failure (HF) and cardiomyocyte-targeted viral-based S100A1 gene transfer rescued failing myocardium in small animal models in vivo and in vitro via improved systolic and diastolic sarcoplasmic reticulum Ca-handling. We therefore hypothesized that cardioselective AAV9-S100A1 gene therapy will improve cardiac performance in a large animal experimental HF model under clinical conditions. Methods and Results: Left ventricular (LV) posterolateral myocardial infarction (MI) was induced in pigs by occlusion of the left coronary circumflex artery and resulted in LV failure (HF) 2 weeks post-MI reflected by a 40% and 27% reduction in LV +dp/dt max. and EF, respectively, as assessed by LV catheterization and echocardiography. Post-MI HF pigs were then randomized for retroinfusion of AAV9-luciferase (luc; n=6, 1.5×10 13 total viral particles, tvp) and AAV9-S100A1 (S100A1; n=6, 1.5×10 13 tvp) driven by a cardioselective promoter via the anterior cardiac vein while the left anterior descending artery was temporarily occluded. 14 weeks after cardiac gene transfer, the S100A1-treated HF group showed significantly enhanced S100A1 protein expression (+46.7±17.9%, P<0.05 vs. control groups) in targeted remote LV myocardium and improved indices of cardiac function and remodeling (luc vs. S100A1: +dp/dtmax: 983±81 vs. 1526±83 mmHg/s, EF: 39±2.1 vs. 61±3.7 %, P<0.05 S100A1 vs. luc, LV endsystolic diameter: luc 4.45±0.1 vs. S100A1 3.43 ±0.1 cm, P<0.05 S100A1 vs. luc, HR: 72±4 vs. 69±2, beats/min, P=n.s. S100A1 vs. luc). Importantly, analyses of renal, hepatic and hematopoetic function showed no alteration as assessed by unchanged transaminases, retention values and white blood cell counts compared to sham pigs. Conclusions: Our translational study provides proof of concept that AAV9-S100A1 based HF gene therapy is feasible and restores cardiac function in a large animal HF model under clinical conditions. Next, certified toxicological analysis and different AAV9-S100A1 dosage protocols will be assessed to eventually advance to first phase I/II clinical studies determining therapeutic efficiency of cardiac S100A1 gene therapy in HF patients.

Pirfenidone exhibits cardioprotective effects by regulating myocardial fibrosis and vascular permeability in pressure-overloaded hearts

2015 ◽  
Vol 309 (3) ◽  
pp. H512-H522 ◽  
Author(s):  
Kiyoshi Yamagami ◽  
Toru Oka ◽  
Qi Wang ◽  
Takamaru Ishizu ◽  
Jong-Kook Lee ◽  
...  
Keyword(s):  
Heart Failure ◽  
Endothelial Cells ◽  
Vascular Permeability ◽  
Molecular Mechanisms ◽  
Cardiac Fibrosis ◽  
Transforming Growth Factor ◽  
Cardiac Fibroblasts ◽  
Chronic Phase ◽  
Vehicle Group

Although cardiac fibrosis causes heart failure, its molecular mechanisms remain elusive. In this study, we investigated the mechanisms of cardiac fibrosis and examined the effects of the antifibrotic drug pirfenidone (PFD) on chronic heart failure. To understand the responsible mechanisms, we generated an in vivo pressure-overloaded heart failure model via transverse aortic constriction (TAC) and examined the effects of PFD on chronic-phase cardiac fibrosis and function. In the vehicle group, contractile dysfunction and left ventricle fibrosis progressed further from 4 to 8 wk after TAC but were prevented by PFD treatment beginning 4 wk after TAC. We isolated cardiac fibroblasts and vascular endothelial cells from the left ventricles of adult male mice and investigated the cell-type-specific effects of PFD. Transforming growth factor-β induced upregulated collagen 1 expression via p38 phosphorylation and downregulated claudin 5 (Cldn5) expression in cardiac fibroblasts and endothelial cells, respectively; both processes were inhibited by PFD. Moreover, PFD inhibited changes in the collagen 1 and Cldn5 expression levels, resulting in reduced fibrosis and serum albumin leakage into the interstitial space during the chronic phase in TAC hearts. In conclusion, PFD inhibited cardiac fibrosis by suppressing both collagen expression and the increased vascular permeability induced by pressure overload.

scholarly journals Cardiac AAV9-S100A1 Gene Therapy Rescues Post-Ischemic Heart Failure in a Preclinical Large Animal Model

2011 ◽  
Vol 3 (92) ◽  
pp. 92ra64-92ra64 ◽  
Author(s):  
S. T. Pleger ◽  
C. Shan ◽  
J. Ksienzyk ◽  
R. Bekeredjian ◽  
P. Boekstegers ◽  
...  
Keyword(s):  
Heart Failure ◽  
Gene Therapy ◽  
Animal Model ◽  
Ischemic Heart ◽  
Large Animal Model ◽  
Large Animal ◽  
Ischemic Heart Failure

scholarly journals CRISPR-Cas9 in gene therapy: much control on breaking, little control on repairing

2015 ◽  
Author(s):  
Kaveh Daneshvar
Keyword(s):  
Gene Therapy ◽  
Dna Repair ◽  
Immune Responses ◽  
Genome Editing ◽  
Biomedical Research ◽  
Target Cells ◽  
Target Dna ◽  
In Vivo Delivery ◽  
Target Effects

Recent advances in CRISPR-Cas9 genome editing tool have made great promises to basic and biomedical research as well as gene therapy. Efforts to make the CRISPR-Cas9 system applicable in gene therapy are largely focused on two aspects: 1) increasing the specificity of this system by eliminating off-target effects, and 2) optimizing in vivo delivery of the CRISPR-Cas9 DNA constructs to target cells and limiting the expression of Cas9 and gRNA to prevent toxicity immune responses. However, there is an unnoted but crucial consideration about the mode of DNA repair at the lesion caused by CRISPR-Cas9. In this commentary, I briefly highlight recent publications on in vivo use of the CRISPR-Cas9 system in gene therapy. I then discuss the undesired on-target DNA repair events that can occur as a result of the activity of CRISPR-Cas9. Overall, this commentary underscores the need for more study on controlled DNA repair in systems targeted with CRISPR-Cas9 genome editing tools.

P1599Sodium channel gene therapy with dual adeno-associated viral vectors

2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
G J J Boink ◽  
J Wang ◽  
M Klerk ◽  
V M Christoffels ◽  
H L Tan ◽  
...  
Keyword(s):  
Gene Therapy ◽  
Sodium Channel ◽  
Mrna Expression ◽  
Neonatal Rat ◽  
Target Cells ◽  
Aav Vector ◽  
Channel Gene ◽  
Cardiac Sodium Channel

Abstract Background Sodium channel gene therapy carries significant potential for treatment of acquired and inherited arrhythmias. However, delivery is challenging to the length of the transgene that exceeds the packaging capacity of Adeno-Associated Virus (AAV), the most advanced long-term gene therapy vector to date. To overcome this issue, we have developed dual AAV vectors for the delivery of the skeletal muscle sodium channel 1 (SkM1). Purpose To achieve cardiac delivery of SkM1 and other large therapeutic genes using dual AAV vectors. Methods Dual AAV vectors were constructed, containing SkM1 gene fragments that allow reconstruction in the target cells by trans-splicing and recombination. An oversized single AAV vector containing SkM1 served as a control. HEK293T cells and neonatal rat ventricular cardiomyocytes (NRVMs) were transduced with dual AAV vectors or oversized single AAV vector at an MOI of 50,000 per vector. Etoposide and Teniposide were added 2h before transduction to improve the efficiency. SkM1 mRNA and protein were isolated 3 days post transduction and the expression was detected by RT-qPCR and Western blot. Results Robust full-length SkM1 protein expression was detected in both HEK cells and NRVMs transduced by dual AAV vectors while no expression was detected in the control. Transduction with dual AAV vectors also showed significantly higher SkM1 mRNA expression in both cell types (4 to 29-fold) comparing to oversized single AAV vector. Moreover, a relatively high level of SkM1 mRNA expression was achieved in NRVM; 22-fold higher than the native cardiac sodium channel. Conclusion Efficient delivery and expression of SkM1 was successfully achieved in vitro by hybrid dual AAV vectors. This approach supports the application of SkM1 and other sodium channel antiarrhythmic gene therapies. In vivo validation and functional testing are currently in on-going.

scholarly journals Efficient and Highly Specific Gene Transfer Using Mutated Lentiviral Vectors Redirected with Bispecific Antibodies

mBio ◽  
2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Christina L. Parker ◽  
Timothy M. Jacobs ◽  
Justin T. Huckaby ◽  
Dimple Harit ◽  
Samuel K. Lai
Keyword(s):  
Gene Therapy ◽  
Gene Delivery ◽  
Fluorescent Protein ◽  
Ex Vivo ◽  
Endosomal Escape ◽  
Bispecific Antibodies ◽  
Target Cells ◽  
Specific Gene ◽  
Targeted Gene Delivery

ABSTRACT Despite their exceptional potencies, the broad tropism of most commonly used lentivirus (LV) vectors limits their use for targeted gene delivery in vivo. We hypothesized that we could improve the specificity of LV targeting by coupling (i) reduction of their binding to off-target cells with (ii) redirection of the vectors with a bispecific antibody (bsAb) that binds both LV and receptors on target cells. As a proof of concept, we pseudotyped nonreplicating LV using a mutated Sindbis envelope (mSindbis) with ablated binding to native receptors, while retaining the capacity to facilitate efficient fusion and endosomal escape. We then evaluated the transduction potencies of the mSindbis LV for HER2-positive (HER2+) (SKBR3) breast and HER2-negative (HER2−) (A2780) cells when redirected with different bsAbs. mSindbis LV alone failed to induce appreciable green fluorescent protein (GFP) expression in either cell. When mixed with HER2-targeting bsAb, mSindbis LV was exceptionally potent, transducing 12% to 16% of the SKBR3 cells at a multiplicity of infection (MOI [ratio of viral genome copies to target cells]) of 3. Transduction was highly specific, resulting in ∼50-fold-greater selectivity toward SKBR3 cells versus A2780 cells. Redirecting mSindbis LV led to a 10-fold improvement in cell-specific targeting compared to redirecting wild-type Sindbis LV with the same bsAb, underscoring the importance of ablating native virus tropism in order to maximize targeting specificity. The redirection of mutated LV using bsAb represents a potent and highly versatile platform for targeted gene therapy. IMPORTANCE The goal of gene therapy is specific delivery and expression of therapeutic genes to target cells and tissues. Common lentivirus (LV) vectors are efficient gene delivery vehicles but offer little specificity. Here, we report an effective and versatile strategy to redirect LV to target cells using bispecific antibodies (bsAbs) that bind both cell receptors and LV envelope domains. Importantly, we ablated the native receptor binding of LV to minimize off-target transduction. Coupling bsAb specificity and ablated native LV tropism synergistically enhanced the selectivity of our targeted gene delivery system. The modular nature of our bsAb-based redirection enables facile targeting of the same LV to diverse tissues/cells. By abrogating the native broad tropism of LV, our bsAb-LV redirection strategy may enable lentivirus-based gene delivery in vivo, expanding the current use of LV beyond ex vivo applications.

Abstract 76: Meox1 is a Cell-cycle Oscillator Required for Mitotic Transition and Proliferation in Cardiac Fibroblasts

2014 ◽  
Vol 115 (suppl_1) ◽  
Author(s):  
Shuichiro Higo ◽  
Yoshihiro Asano ◽  
Yuki Masumura ◽  
Yasushi Sakata ◽  
Masafumi Kitakaze ◽  
...  
Keyword(s):  
Heart Failure ◽  
Cell Cycle ◽  
Cardiac Fibroblasts ◽  
Tissue Fibrosis ◽  
Cell Cycle Synchronization ◽  
M Phase ◽  
A Cell ◽  
End Stage

Background: Tissue fibrosis plays important roles in the pathogenesis of chronic diseases, including heart failure. The mechanism underlying interstitial fibroblast proliferation is a promising analytical target for therapeutic applications. Here we developed quantitative epigenome profiling to identify a critical regulator in interstitial cell populations that emerges during the progression of heart failure. Methods and Results: We subjected pressure-overloaded hearts of mice to trimethylated histone H3 lysine 4 (H3K4me3) ChIP-sequence and RNA-sequence. Expression analysis followed by quantitative H3K4me3 profiling identified 45 fibrosis-related genes with significant H3K4me3 enrichment in failing hearts, including Meox1 transcription factor. Meox1 emerged in the interstitial fibrotic region in failing heart, and intriguingly Meox1 was expressed in the limited population of cardiac fibroblasts both in vivo and in vitro. Meox1-positive fibroblasts were increased in response to a paracrine signal from cardiomyocytes, and knockdown of Meox1 completely inhibited the reactive proliferation of cardiac fibroblasts stimulated by conditioned medium from cardiomyocytes. Gene expression profiling combined with siRNAs clarified that Meox1 depletion resulted in down regulation in the mitosis-related genes including Aurora B kinase. Indeed, Meox1 depletion decreased the cells under mitosis, but conversely increased the proportion of DNA synthesizing cells, thereby inhibited mitotic transition. The cell-cycle synchronization analysis and promoter analysis using live-cell imaging clarified that Meox1 oscillated throughout the cell-cycle and specifically emerged in G2/M phase. Finally, we revealed that Meox1 heterogenously expressed in the interstitial fibrotic are of human ventricular heart tissues from patients with end-stage heart failure. Notably, Meox1 expression was significantly correlated with the fibrosis-related genes in diseased ventricular heart tissues (n=15), suggesting the pathological relevance in clinical settings. Conclusion: Our findings identify a novel cell-cycle regulator and propose that Meox1 is a potential target for therapies aimed at preventing tissue fibrosis.

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