First-in-human in vivo genome editing via AAV-zinc-finger nucleases for mucopolysaccharidosis I/II and hemophilia B.

Zinc-finger nuclease (ZFN)-based in vivo genome editing is a novel treatment that can potentially provide lifelong protein replacement with single intravenous administration. Three first-in-human open-label ascending single-dose phase 1/2 studies were performed in parallel (starting November 2017) primarily to assess safety and tolerability of ZFN in vivo editing therapy in mucopolysaccharidosis I (MPS I) (n = 3), MPS II (n = 9), and hemophilia B (n = 1). Treatment was well tolerated with no serious treatment-related adverse events. At the 1e13 vg/kg dose, evidence of genome editing was detected through albumin-transgene fusion transcripts in liver for MPS II (n = 2) and MPS I (n = 1) subjects. The MPS I subject also had a transient increase in leukocyte iduronidase activity to the lower normal range. At the 5e13 vg/kg dose, one MPS II subject had a transient increase in plasma iduronate-2-sulfatase approaching normal levels and one MPS I subject approached mid-normal levels of leukocyte iduronidase activity with no evidence of genome editing. The hemophilia B subject was not able to decrease use of factor IX concentrate; genome editing could not be assessed. Overall, ZFN in vivo editing therapy had a favorable safety profile with evidence of targeted genome editing in liver, but no long-term enzyme expression in blood.

Improvement of Local Cell Delivery Using Helix Transendocardial Delivery Catheter in a Porcine Heart.

Cardiac regeneration strategies using stem cells have shown variable and inconsistent results with respect to patient cardiac function and clinical outcomes. There has been increasing consensus that improving the efficiency of delivery may improve results. The Helix transendocardial delivery system (BioCardia Inc.) has been developed to enable percutaneous transendocardial biotherapeutic delivery. Therefore, we evaluated cell retention using this unique system compared with direct transepicardial injection and intracoronary infusion in an animal model.Twelve healthy swine were used in this study. 18Fluorodeoxyglucose (FDG)-labeled bone marrow mononuclear cells were delivered via percutaneous transendocardial route using the Helix system (TE group, n = 5), via direct transepicardial injection using a straight 27-gauge needle in an open chest procedure (TP group, n = 4), or via percutaneous intracoronary (IC) infusion (IC group, n = 3). One hour after cell delivery, the distribution of injected cells within the myocardium was assessed by PET-CT. Regions of interest were defined and their signals were compared in each group. Retention rates were calculated as a percentage of the comparing signal.The distribution of injected cells in the myocardium was higher in the TE group (17.9%) than in the TP group (6.0%, versus TE, P < 0.001) and the IC group (1.0%, versus TE, P < 0.001). Consistent with previous reports, there were signal distributions in the lungs, liver, and kidneys in qualitative whole body PET assessment.TE cell delivery using a helical infusion catheter is more efficient in cell retention than either TP delivery or IC delivery using PET-CT analysis.

Transendocardial mesenchymal stem cells and mononuclear bone marrow cells for ischemic cardiomyopathy: the TAC-HFT randomized trial.

IMPORTANCE: Whether culture-expanded mesenchymal stem cells or whole bone marrow mononuclear cells are safe and effective in chronic ischemic cardiomyopathy is controversial. OBJECTIVE: To demonstrate the safety of transendocardial stem cell injection with autologous mesenchymal stem cells (MSCs) and bone marrow mononuclear cells (BMCs) in patients with ischemic cardiomyopathy. DESIGN, SETTING, AND PATIENTS: A phase 1 and 2 randomized, blinded, placebo-controlled study involving 65 patients with ischemic cardiomyopathy and left ventricular (LV) ejection fraction less than 50% (September 1, 2009-July 12, 2013). The study compared injection of MSCs (n=19) with placebo (n = 11) and BMCs (n = 19) with placebo (n = 10), with 1 year of follow-up. INTERVENTIONS: Injections in 10 LV sites with an infusion catheter. MAIN OUTCOMES AND MEASURES: Treatment-emergent 30-day serious adverse event rate defined as a composite of death, myocardial infarction, stroke, hospitalization for worsening heart failure, perforation, tamponade, or sustained ventricular arrhythmias. RESULTS: No patient had a treatment-emergent serious adverse events at day 30. The 1-year incidence of serious adverse events was 31.6% (95% CI, 12.6% to 56.6%) for MSCs, 31.6% (95% CI, 12.6%-56.6%) for BMCs, and 38.1% (95% CI, 18.1%-61.6%) for placebo. Over 1 year, the Minnesota Living With Heart Failure score improved with MSCs (-6.3; 95% CI, -15.0 to 2.4; repeated measures of variance, P=.02) and with BMCs (-8.2; 95% CI, -17.4 to 0.97; P=.005) but not with placebo (0.4; 95% CI, -9.45 to 10.25; P=.38). The 6-minute walk distance increased with MSCs only (repeated measures model, P = .03). Infarct size as a percentage of LV mass was reduced by MSCs (-18.9%; 95% CI, -30.4 to -7.4; within-group, P = .004) but not by BMCs (-7.0%; 95% CI, -15.7% to 1.7%; within-group, P = .11) or placebo (-5.2%; 95% CI, -16.8% to 6.5%; within-group, P = .36). Regional myocardial function as peak Eulerian circumferential strain at the site of injection improved with MSCs (-4.9; 95% CI, -13.3 to 3.5; within-group repeated measures, P = .03) but not BMCs (-2.1; 95% CI, -5.5 to 1.3; P = .21) or placebo (-0.03; 95% CI, -1.9 to 1.9; P = .14). Left ventricular chamber volume and ejection fraction did not change. CONCLUSIONS AND RELEVANCE: Transendocardial stem cell injection with MSCs or BMCs appeared to be safe for patients with chronic ischemic cardiomyopathy and LV dysfunction. Although the sample size and multiple comparisons preclude a definitive statement about safety and clinical effect, these results provide the basis for larger studies to provide definitive evidence about safety and to assess efficacy of this new therapeutic approach. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00768066.

An open-label dose escalation study to evaluate the safety of administration of nonviral stromal cell-derived factor-1 plasmid to treat symptomatic ischemic heart failure.

RATIONALE: Preclinical studies indicate that adult stem cells induce tissue repair by activating endogenous stem cells through the stromal cell-derived factor-1:chemokine receptor type 4 axis. JVS-100 is a DNA plasmid encoding human stromal cell-derived factor-1. OBJECTIVE: We tested in a phase 1, open-label, dose-escalation study with 12 months of follow-up in subjects with ischemic cardiomyopathy to see if JVS-100 improves clinical parameters. METHODS AND RESULTS: Seventeen subjects with ischemic cardiomyopathy, New York Heart Association class III heart failure, with an ejection fraction ≤40% on stable medical therapy, were enrolled to receive 5, 15, or 30 mg of JVS-100 via endomyocardial injection. The primary end points for safety and efficacy were at 1 and 4 months, respectively. The primary safety end point was a major adverse cardiac event. Efficacy end points were change in quality of life, New York Heart Association class, 6-minute walk distance, single photon emission computed tomography, N-terminal pro-brain natruretic peptide, and echocardiography at 4 and 12 months. The primary safety end point was met. At 4 months, all of the cohorts demonstrated improvements in 6-minute walk distance, quality of life, and New York Heart Association class. Subjects in the 15- and 30-mg dose groups exhibited improvements in 6-minute walk distance (15 mg: median [range]: 41 minutes [3-61 minutes]; 30 mg: 31 minutes [22-74 minutes]) and quality of life (15 mg: -16 points [+1 to -32 points]; 30 mg: -24 points [+17 to -38 points]) over baseline. At 12 months, improvements in symptoms were maintained. CONCLUSIONS: These data highlight the importance of defining the molecular mechanisms of stem cell-based tissue repair and suggest that overexpression of stromal cell-derived factor-1 via gene therapy is a strategy for improving heart failure symptoms in patients with ischemic cardiomyopathy.

Assessment of safety, accuracy, and human CD34+ cell retention after intramyocardial injections with a helical needle catheter in a porcine model.

OBJECTIVES: Assess accuracy of Helix injections via fluoroscopic-mapping and evaluate delivery safety. BACKGROUND: Percutaneous intramyocardial-delivery of agents must be safe and accurate; retention is also important. A delivery system (Helical Infusion/Morph Guide-Catheter, Biocardia Inc) has been developed to improve maneuverability and stability of catheter-needle-myocardium intersection. METHODS: Accuracy and safety: 12 swine underwent LV and coronary angiography via 8F sheath. Targeted delivery was assigned into LAD, LCX, or RCA. System was advanced into LV and 6 targeted intramyocardial dye injections (5 mm apart) delivered using fluoroscopy. After euthanization, hearts underwent gross and histologic evaluation. Retention was assessed by iron-oxide and fluorochrome labeled CD34+ cells. Cells were injected into 6 swine using same techniques. Delivery system was advanced into LV, and injections delivered using fluoroscopy. Euthanization was performed at 2 hr and hearts formalin fixed. MRI was performed on 6 treated hearts and 4 untreated controls. Blinded analysis performed by 2 radiologists. Two treated hearts underwent immunohistological analysis. RESULTS: Accuracy and safety evaluation: 71/72 injections (98.6%) were within prespecified zone; 7/72 (9.7%) less than 5 mm apart. No adverse events occurred. MRI-presence of iron-oxide labeled CD34+ cells were correctly identified in 95% (19/20) of imaged injections. Anti-CD34+ antibody staining and fluorescence microscopy confirmed CD34+ cells in myocardium. Histology confirmed cell viability at fixation. CONCLUSIONS: Helix system was accurate and safe. Retention of CD34+ cells was confirmed by MRI and immunohistology. Further preclinical studies are needed to characterize retention over time and quantify efficiency. Studies are needed to confirm accuracy, safety, and retention in humans.

Comparison of allogeneic vs autologous bone marrow­derived mesenchymal stem cells delivered by transendocardial injection in patients with ischemic cardiomyopathy: the POSEIDON randomized trial.

CONTEXT: Mesenchymal stem cells (MSCs) are under evaluation as a therapy for ischemic cardiomyopathy (ICM). Both autologous and allogeneic MSC therapies are possible; however, their safety and efficacy have not been compared. OBJECTIVE: To test whether allogeneic MSCs are as safe and effective as autologous MSCs in patients with left ventricular (LV) dysfunction due to ICM. DESIGN, SETTING, AND PATIENTS: A phase 1/2 randomized comparison (POSEIDON study) in a US tertiary-care referral hospital of allogeneic and autologous MSCs in 30 patients with LV dysfunction due to ICM between April 2, 2010, and September 14, 2011, with 13-month follow-up. INTERVENTION: Twenty million, 100 million, or 200 million cells (5 patients in each cell type per dose level) were delivered by transendocardial stem cell injection into 10 LV sites. MAIN OUTCOME MEASURES: Thirty-day postcatheterization incidence of predefined treatment-emergent serious adverse events (SAEs). Efficacy assessments included 6-minute walk test, exercise peak VO2, Minnesota Living with Heart Failure Questionnaire (MLHFQ), New York Heart Association class, LV volumes, ejection fraction (EF), early enhancement defect (EED; infarct size), and sphericity index. RESULTS: Within 30 days, 1 patient in each group (treatment-emergent SAE rate, 6.7%) was hospitalized for heart failure, less than the prespecified stopping event rate of 25%. The 1-year incidence of SAEs was 33.3% (n = 5) in the allogeneic group and 53.3% (n = 8) in the autologous group (P = .46). At 1 year, there were no ventricular arrhythmia SAEs observed among allogeneic recipients compared with 4 patients (26.7%) in the autologous group (P = .10). Relative to baseline, autologous but not allogeneic MSC therapy was associated with an improvement in the 6-minute walk test and the MLHFQ score, but neither improved exercise VO2 max. Allogeneic and autologous MSCs reduced mean EED by −33.21% (95% CI, −43.61% to −22.81%; P < .001) and sphericity index but did not increase EF. Allogeneic MSCs reduced LV end-diastolic volumes. Low-dose concentration MSCs (20 million cells) produced greatest reductions in LV volumes and increased EF. Allogeneic MSCs did not stimulate significant donor-specific alloimmune reactions. CONCLUSIONS: In this early-stage study of patients with ICM, transendocardial injection of allogeneic and autologous MSCs without a placebo control were both associated with low rates of treatment-emergent SAEs, including immunologic reactions. In aggregate, MSC injection favorably affected patient functional capacity, quality of life, and ventricular remodeling. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01087996.

Transendocardial autologous bone marrow in myocardial infarction induced heart failure, two-year follow-up in an open-label phase I safety study (the TABMMI study).

AIMS: To assess the hypothesis that fluoroscopically-guided helical needle transendocardial delivery of autologous bone marrow (ABM) mononuclear cells (MNCs) in chronic post myocardial infarction patients is safe and improves ejection fraction (EF). METHODS AND RESULTS: Twenty ischaemic heart failure patients with an EF ≤40% were enrolled. ABMMNCs were prepared, counted for CD34+ and CD133+ content, and delivered percutaneously to the heart at 5 to 10 peri-infarct sites. Two-dimensional (2D) transthoracic echocardiography, EF measurements, Holter, and exercise tolerance time (ETT) were performed at baseline, one week (wk), and 6, 12, and 24 months (mo). 96±29 million ABMMNCs were injected into 8.5±2.6 peri-infarct sites over 42±17 minutes (n=20). There were no adverse events associated with the catheter-based cell transplantation procedure or significant increases in ventricular events on Holter. EF improved over baseline from 34.9±4.3% to 41.9±5.1% at 12 mo to 42.2±7.1% (p=0.00005) at 24 mo. ETT improvements were statistically significant from 246±113 sec to 373±183 sec at 12 mo and 371±181 sec at 24 mo (p=0.006). CONCLUSIONS: ABMMNCs delivered with the helical needle transendocardial catheter was safe in this uncontrolled open label study. Increased EF and ETT support the safety of the procedure and technologies involved and warrant additional investigation.

Intramyocardial stem cell injection in patients with ischemic cardiomyopathy: functional recovery and reverse remodeling.

RATIONALE: Transcatheter, intramyocardial injections of bone marrow-derived cell therapy produces reverse remodeling in large animal models of ischemic cardiomyopathy. OBJECTIVE: We used cardiac MRI (CMR) in patients with left ventricular (LV) dysfunction related to remote myocardial infarction (MI) to test the hypothesis that bone marrow progenitor cell injection causes functional recovery of scarred myocardium and reverse remodeling. METHODS AND RESULTS: Eight patients (aged 57.2±13.3 years) received transendocardial, intramyocardial injection of autologous bone marrow progenitor cells (mononuclear or mesenchymal stem cells) in LV scar and border zone. All patients tolerated the procedure with no serious adverse events. CMR at 1 year demonstrated a decrease in end diastolic volume (208.7±20.4 versus 167.4±7.32 mL; P=0.03), a trend toward decreased end systolic volume (142.4±16.5 versus 107.6±7.4 mL; P=0.06), decreased infarct size (P<0.05), and improved regional LV function by peak Eulerian circumferential strain in the treated infarct zone (-8.1±1.0 versus -11.4±1.3; P=0.04). Improvements in regional function were evident at 3 months, whereas the changes in chamber dimensions were not significant until 6 months. Improved regional function in the infarct zone strongly correlated with reduction of end diastolic volume (r(2)=0.69, P=0.04) and end systolic volume (r(2)=0.83, P=0.01). CONCLUSIONS: These data suggest that transcatheter, intramyocardial injections of autologous bone marrow progenitor cells improve regional contractility of a chronic myocardial scar, and these changes predict subsequent reverse remodeling. The findings support the potential clinical benefits of this new treatment strategy and ongoing randomized clinical trials.

Rationale and design of the Transendocardial Injection of Autologous Human Cells (bone marrow or mesenchymal) in Chronic Ischemic Left Ventricular Dysfunction and Heart Failure Secondary to Myocardial Infarction (TAC-HFT) trial: A randomized, double-blind, placebo-controlled study of safety and efficacy.

Although there is tremendous interest in stem cell (SC)-based therapies for cardiomyopathy caused by chronic myocardial infarction, many unanswered questions regarding the best approach remain. The TAC-HFT study is a phase I/II randomized, double-blind, placebo-controlled trial designed to address several of these questions, including the optimal cell type, delivery technique, and population. This trial compares autologous mesenchymal SCs (MSCs) and whole bone marrow mononuclear cells (BMCs). In addition, the study will use a novel helical catheter to deliver cells transendocardially. Although most trials have used intracoronary delivery, the optimal method is unknown and data suggest that the transendocardial approach may have important advantages. Several trials support the benefit of SCs in patients with chronic ischemic cardiomyopathy (ICMP), although the sample sizes have been small and the number of trials sparse. After a pilot phase of 8 patients, 60 patients with ICMP (left ventricular ejection fraction 15%-50%) will be randomized to group A (30 patients further randomized to receive MSC injection or placebo in a 2:1 fashion) or group B (30 patients further randomized to BMCs or placebo in a 2:1 fashion). All patients will undergo bone marrow aspiration and transendocardial injection of SCs or placebo. The primary and secondary objectives are, respectively, to demonstrate the safety and efficacy (determined primarily by cardiac magnetic resonance imaging) of BMCs and MSCs administered transendocardially in patients with ICMP.

Cell therapy for severe chronic heart failure: the Luxembourg experience.

Intracoronary infusion of autologous bone marrow cells (CTX) has been shown to improve myocardial function in post infarct patients and in patients with chronic ischemic cardiomyopathy. Whether CTX affects exercise-induced changes in cardiac deformation and mitral regurgitation (MR) in patients with end stage heart failure has not been studied. In this small pilot study, eleven patients with chronic ischemic cardiomyopathy, ejection fraction (EF) <25%, no inducible ischemia and heart failure class NYHA III underwent CTX. Symptom-limited bicycle exercise echocardiography was performed pre- and 4 months post CTX and maximum systolic strain (msyepsilon), peak systolic strain rate (psysr) and effective regurgitant orifice of MR (ERO) were determined. There were no complications related to the procedure. The overall clinical benefit of CTX was limited with a trend towards improvement (NYHA 3.0+/-0.1 pre and 2.7+/-0.2 post CTX, p=0.06). The EF did not improve after CTX. The wall motion score index (WMSI) did not change at rest but decreased significantly during exercise (1.48+/-0.16 vs. 1.44+/-0.17, p=0.01). In conclusion, CTX may improve cardiac deformation and MR during exercise in patients with severe chronic heart failure when viable areas are targeted.

Adenosine inhibits matrix metalloproteinase-9 secretion by neutrophils: implication of A2a receptor and cAMP/PKA/Ca2+ pathway.

Matrix metalloproteinases (MMPs), and in particular MMP-9 secreted by neutrophils, are capable of degrading the matrix components of the heart and are thought to be the driving force behind myocardial matrix remodeling after infarction. Adenosine, a naturally produced nucleoside, has been shown to have cardioprotective effects and to inhibit secretion of various cytokines. The aim of our study was to determine the effect of adenosine on the secretion of MMP-9 by neutrophils. Neutrophils were isolated from healthy volunteers through Ficoll and Dextran sedimentation. Neutrophils were activated by N-formylmethionyl-leucyl-phenylalanine (fMLP) in the presence or absence of adenosine or adenosine analogs. Zymography and enzyme linked immunosorbent assay were used to measure MMP-9 secretion. Adenosine (1 micromol/L) decreased the fMLP-induced MMP-9 secretion by 30+/-2% (n=8, P<0.001). The effect was dose-dependent and was not specific to fMLP because adenosine also inhibited MMP-9 secretion by LPS- or H(2)O(2)-stimulated neutrophils. The effect of adenosine was mimicked by the adenosine A2a receptor agonist CGS21680 and was inhibited by both the A2a antagonist SCH5826 and A2a RNA silencing. The A3 agonist IB-MECA moderately decreased fMLP-induced MMP-9 secretion. Agonists and antagonists of the other types of adenosine receptors had no significant effect. Adenosine increased intracellular cAMP concentration and accelerated the return to baseline of the intracytoplasmic calcium peak. The inhibition of MMP-9 secretion by adenosine, as well as the calcium effect, was prevented by the protein kinase A inhibitor H-89. In conclusion, we show here that adenosine inhibits MMP-9 secretion by neutrophils. Our results suggest that this effect implies the A2a receptor and is mediated through the cAMP/PKA/Ca(2+) pathway. Therefore, adenosine may represent a new approach to prevent matrix degradation and remodeling after myocardial injury.

Improvement of exercise-induced cardiac deformation after cell therapy for severe chronic ischemic heart failure.

BACKGROUND: Intracoronary infusion of autologous bone marrow cells (CTX) has been shown to improve myocardial function in postinfarct patients and in patients with chronic ischemic cardiomyopathy. Whether CTX affects exercise-induced changes in cardiac deformation and mitral regurgitation (MR) in patients with end-stage heart failure has not been studied. METHODS AND RESULTS: In this small pilot study, 11 patients with chronic ischemic cardiomyopathy, ejection fraction (EF) <25%, no inducible ischemia and heart failure class New York Heart Association (NYHA) III underwent CTX. Symptom-limited bicycle exercise echocardiography was performed pre- and 4 months post-CTX and maximum systolic strain (msyepsilon), peak systolic strain rate (psysr), and effective regurgitant orifice of MR (ERO) were determined. There were no complications related to the procedure. The overall clinical benefit of CTX was limited with a trend towards improvement (NYHA 3.0 +/- 0.1 pre- and 2.7 +/- 0.2 post-CTX, P = .06). The EF did not improve after CTX. The wall motion score index did not change at rest but decreased significantly during exercise (1.48 +/- 0.16 versus 1.44 +/- 0.17, P = .01). In patients with non-viable areas, msyepsilon, psysr, and ERO were not affected by CTX. However, in patients with viable areas, msyepsilon and psysr appeared to increase during exercise and ERO appeared to decrease from 19 +/- 5 to 16 +/- 5 mm(2). This effect was not apparent at rest and more pronounced with inferior viability. CONCLUSION: CTX may improve cardiac deformation and MR during exercise in patients with severe chronic heart failure when viable areas are targeted.

Matrix metalloproteinase-9 is a marker of heart failure after acute myocardial infarction.

BACKGROUND: Matrix metalloproteinases (MMPs) have been associated with the development of left ventricular remodeling after myocardial infarction (MI). We sought to determine whether peripheral levels of MMPs can be used as a risk marker for the development of congestive heart failure (CHF) after acute MI. METHODS AND RESULTS: Plasma levels of MMP-2, MMP-9, C-reactive protein (hs-CRP), tumor necrosis factor-alpha (TNF-alpha), and pro-brain natriuretic peptide (pro-BNP) were measured in 109 consecutive patients with acute MI treated with primary mechanical reperfusion. Echocardiographic assessment of left ventricular wall motion index was performed during admission. Patients were followed for the development of CHF. Left ventricular function and volumes were determined after 2 years with radionuclide ventriculography. During 2-year follow-up, 15 patients developed congestive heart failure (CHF). Using multivariate analysis, MMP-9 levels were the only circulating factor predictive of late onset CHF. Patients who had high MMP-9 levels had a significant risk of late onset CHF (OR of 6.5, P < or = .006) and left ventricular remodeling (DeltaEF = -9%, P = .03, and Deltaend-diastolic volume = +13 mL, P = .03). MMP-2, TNF-alpha, hs-CRP, creatine kinase, and pro-BNP were not predictive of late onset CHF. CONCLUSION: MMP-9 levels may hold prognostic significance in MI patients.

Plasma storage at -80 degrees C does not protect matrix metalloproteinase-9 from degradation.

Recently, matrix metalloproteinase-9 (MMP-9) has been identified as a cardiovascular risk marker and is increasingly being determined in clinical studies. Among other matrix metalloproteinases, MMP-9 is known to be self-activable, as the cleavage of the propeptide leads to the formation of an active enzyme. In such a case the issue of storage of biological samples such as plasmas is of outstanding importance, as an enzymatic activity, although minimal, may remain at common storage temperature, i.e., -80 degrees C. Since 2000 our institute has created a plasma library from patients presenting with acute myocardial infarction. Recently, the evaluation of the MMP-9 led to the surprise of finding a dramatically low level of detectable enzyme in the oldest plasma samples. By using zymography, enzyme-linked immunosorbent assay and Western blots, we evaluated new and old samples and found that MMP-9 degrades over time. After 2 years, the detectable total MMP-9 dropped by 65%, and the asymptotic profile of the curve reached a residual 1% level after 43 months. These results were confirmed by zymography and western blotting. TIMP-1, the natural inhibitor of MMP-9 and MMP-2, remained rather stable over time. The results suggest that human plasma MMP-9 levels should be determined as soon as possible after sampling.