Effects of Repetitive Transendocardial CD34+ Cell Transplantation in Patients With Nonischemic Dilated Cardiomyopathy.

RATIONALE: Preclinical data in heart failure models suggest that repetitive stem cell therapy may be superior to single-dose cell administration. OBJECTIVE: We investigated whether repetitive administration of CD34+ cells is superior to single-dose administration in patients with nonischemic dilated cardiomyopathy. METHODS AND RESULTS: Of 66 patients with dilated cardiomyopathy, New York Heart Association functional class III, and left ventricular ejection fraction (LVEF) <40% enrolled in the study, 60 were randomly allocated to repetitive cell therapy (group A, n=30) or single-cell therapy (group B, n=30). Patients received G-CSF (granulocyte colony-stimulating factor) for 5 days, and 80 million CD34+ cells were collected by apheresis and injected transendocardially. In group A, cell therapy was repeated at 6 months. All patients were followed for 1 year, and the primary end point was the difference in change in LVEF between the groups. At baseline, the groups did not differ in age, sex, LVEF, NT-proBNP (N-terminal pro-B-type natriuretic peptide), or 6-minute walk test distance. When directly comparing groups A and B at 1 year, there was no significant difference in change in LVEF (from 32.2±9.3% to 41.2±6.5% in group A and from 30.0±7.0% to 37.9±5.3% in group B, P=0.40). From baseline to 6 months, both groups improved in LVEF (+6.9±3.3% in group A, P=0.001 and +7.1±3.5% in group B, P=0.001), NT-proBNP (-578±211 pg/mL, P=0.02 and -633±305 pg/mL, P=0.01), and 6-minute walk test (+87±21 m, P=0.03 and +92±25 m, P=0.02). In contrast, we observed no significant changes between 6 months and 1 year (LVEF: +2.1±2.3% in group A, P=0.19 and +0.8±3.1% in group B, P=0.56; NT-proBNP: -215±125 pg/mL, P=0.26 and -33±205 pg/mL, P=0.77; 6-minute walk test: +27±11 m, P=0.2 and +12±18 m, P=0.42). CONCLUSIONS: In patients with dilated cardiomyopathy, repetitive CD34+ cell administration does not seem to be associated with superior improvements in LVEF, NT-proBNP, or 6-minute walk test when compared with single-dose cell therapy. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT02248532.

Electroanatomic Properties of the Myocardium Predict Response to CD34+ Cell Therapy in Patients With Ischemic and Nonischemic Heart Failure.

BACKGROUND: We investigated a correlation between electromechanical properties of the myocardium and response to CD34+ cell therapy in patients with chronic heart failure. METHODS AND RESULTS: We enrolled 40 patients with ischemic cardiomyopathy (ICM) and 40 with nonischemic dilated cardiomyopathy (DCM). All patients were in New York Heart Association functional class III and had a left ventricular ejection fraction (LVEF) <40%. CD34+ cells were mobilized by granulocyte colony-stimulating factor and collected via apheresis. Electroanatomic mapping was performed to define areas of myocardial scar and hibernation, and CD34+ cells were injected transendocardially in the hibernating areas. Patient were followed for 6 months; responders were defined as patients with LVEF increase of >5%. At baseline, the groups did not differ in sex, LVEF, creatinine, N-terminal pro-B-type natriuretic peptide or electroanatomic parameters (scar area: 53 ± 18% in ICM vs 55 ± 23% in DCM [P = .83]; hibernating area: 23 ± 13% vs 22 ± 12% [P = .56]). At 6 months we found similar rates of responders in both groups (60% in ICM vs 65% in DCM [P = .95]). When compared with nonresponders, responders had less myocardial scar (47 ± 17% vs 58 ± 15% [P = .003]). CONCLUSIONS: In patients with chronic heart failure due to ICM and DCM we observed similar electroanatomic properties of the myocardium. In both groups, lower myocardial scar burden was associated with better clinical response to CD34+ cell therapy.

Intracoronary transplantation of CD34(+) cells is associated with improved myocardial perfusion in patients with nonischemic dilated cardiomyopathy.

BACKGROUND: We investigated the effects of intracoronary transplantation of CD34(+) cells on myocardial perfusion in patients with nonischemic dilated cardiomyopathy (DCM). METHODS AND RESULTS: We enrolled 21 patients with DCM (left ventricular ejection fraction [LVEF] <40%, New York Heart Association functional class III) who underwent peripheral stem cell mobilization with granulocyte-colony stimulating factor (G-CSF). CD34(+) cells were collected by means of apheresis. Patients underwent myocardial perfusion imaging, and CD34(+) cells were injected in the coronary artery supplying viable segments with reduced myocardial perfusion and regional dysfunction. Myocardial perfusion imaging was repeated 6 months later. Clinical response to stem cell therapy was predefined as a change in LVEF >5%. The majority of patients were men (81%) with an overall mean age 53 ± 9 years, LVEF 25 ± 5%, and 6-minute walking distance 354 ± 71 m. Myocardial perfusion defects at rest were observed in 86% of patients and were more common in the left anterior descending territory (50%). At 6 months' follow-up, there was a significant improvement in rest myocardial perfusion scores (6.3 ± 5.8 vs 3.1 ± 4.3; P < .001), LVEF (25 ± 7% vs 29 ± 8%; P = .005), and 6-minute walking distance (354 ± 71 m vs 404 ± 91 m; P < .001). Responders to stem cell therapy had lower summed rest perfusion score at both baseline (3.2 ± 3.0 vs 9.1 ± 6.3; P = .015) and follow-up (1.0 ± 1.5 vs 5.0 ± 5.1; P = .028). CONCLUSIONS: CD34(+) cell transplantation may lead to improved myocardial perfusion in patients with nonischemic DCM. Patients with less severe myocardial perfusion defects at baseline may have an increased likelihood to respond to intracoronary CD34(+) cell transplantation.

Mutations in the hemochromatosis gene and the clinical outcome of multiple sclerosis.

Multiple sclerosis (MS) is a common inflammatory disease of the central nervous system unsurpassed for its variability in disease outcome. Given a possible role for dysregulation of iron metabolism in MS disease pathogenesis, we investigated whether or not mutations in the HFE gene influence the prognosis of the disease. A cohort of sporadic MS cases, taken from opposite extremes of the putative distribution of long-term outcome using the most stringent clinical criteria to date, was used to determine the role of HFE on MS disease severity. This approach increases the effective sample size by some 40-fold. Genotyping the two sets of MS patients (112 benign and 51 malignant) provided no evidence to suggest that mutations in HFE have any outcome modifying activity, although small effects cannot be ruled out. The frequency of HFE mutations was not different in MS compared to the general population.

Transendocardial CD34+ Cell Transplantation in Noncompaction Cardiomyopathy: First-in-Man Case Study.

Noncompaction cardiomyopathy is a rare congenital heart disorder characterized by an arrest of the myocardial compaction process. This results in the altered formation of coronary microvessels with a resulting decrease in myocardial perfusion. Transendocardial CD34+ cell transplantation has been shown to increase myocardial perfusion and function in patients with non-ischemic heart failure. In our first-in-man case study, we investigated the feasibility, safety and clinical effect of transendocardial CD34+ cell therapy in a patient with noncompaction cardiomyopathy.

Prevalence of H63D, S65C and C282Y hereditary hemochromatosis gene mutations in Slovenian population by an improved high-throughput genotyping assay.

BACKGROUND: Hereditary hemochromatosis (HH) is a common genetic disease characterized by excessive iron overload that leads to multi-organ failure. Although the most prevalent genotype in HH is homozygosity for C282Y mutation of the HFE gene, two additional mutations, H63D and S65C, appear to be associated with a milder form of HH. The aim of this study was to develop a high-throughput assay for HFE mutations screening based on TaqMan technology and to determine the frequencies of HFE mutations in the Slovenian population. METHODS: Altogether, 1282 randomly selected blood donors from different Slovenian regions and 21 HH patients were analyzed for the presence of HFE mutations by an in-house developed real-time PCR assay based on TaqMan technology using shorter non-interfering fluorescent single nucleotide polymorphism (SNP)-specific MGB probes. The assay was validated by RFLP analysis and DNA sequencing. RESULTS: The genotyping assay of the H63D, S65C and C282Y mutations in the HFE gene, based on TaqMan technology proved to be fast, reliable, with a high-throughput capability and 100% concordant with genotypes obtained by RFLP and DNA sequencing. The observed frequency of C282Y homozygotes in the group of HH patients was only 48%, others were of the heterogeneous HFE genotype. Among 1282 blood donors tested, the observed H63D, S65C and C282Y allele frequency were 12.8% (95% confidence interval (CI) 11.5-14.2%), 1.8% (95% CI 1.4-2.5%) and 3.6% (95% CI 3.0-4.5%), respectively. Approximately 33% of the tested subjects had at least one of the three HH mutations, and 1% of them were C282Y homozygotes or compound heterozygotes C282Y/H63D or C282Y/S65C, presenting an increased risk for iron overload disease. A significant variation in H63D allele frequency was observed for one of the Slovenian regions. CONCLUSION: The improved real-time PCR assay for H63D, S65C and C282Y mutations detection is accurate, fast, cost-efficient and ready for routine screening and diagnostic procedures. The genotype frequencies in the Slovenian population agree with those reported for the Central European populations although some deviations where observed in comparison with other populations of Slavic origin. Regional distribution of the mutations should be considered when planning population screening.

Effects of Transendocardial CD34+ Cell Transplantation on Diastolic Parameters in Patients with Nonischemic Dilated Cardiomyopathy.

We sought to evaluate the physiological background and the effects of CD34+ cell transplantation on diastolic parameters in nonischemic dilated cardiomyopathy patients (DCM). We enrolled 38 DCM patients with NYHA class III and LVEF < 40% who underwent transendocardial CD34+ cell transplantation. Peripheral blood CD34+ cells were mobilized by G-CSF, collected via apheresis, and injected transendocardially in the areas of myocardial hibernation. Patients were followed for 1 year. At baseline, estimated filling pressures were significantly elevated (E/e' ≥ 15) in 18 patients (Group A), and moderately elevated (E/e '< 15) in 20 patients (Group B). The groups did not differ in age (54 ± 9 years vs. 52 ± 10 years; p = .62), gender (male: 85% vs. 78%; p = .57), or LVEF (31 ± 7% vs. 34 ± 6%; p = .37). When compared to Group B patients in Group A had more segments with myocardial scar (4.9 ± 2.7 vs. 2.7 ± 2.9; p = .03), myocardial hibernation (2.2 ± 1.6 vs. 0.9 ± 1.1; p = .02), and longer average local relaxation time on electroanatomical mapping (378 ± 41 ms vs. 333 ± 34 ms, p = .01). During follow-up there was an improvement in diastolic parameters in Group A (E/e': from 24.3 ± 12.1 to 16.3 ± 8.0; p = .005), but not in Group B (E/e': from 10.2 ± 3.7 to 13.2 ± 9.1; p = .19). Accordingly, in Group A, we found an increase in 6-minute walk distance (from 463 ± 83 m to 546 ± 91 m; p = .03), and a decrease in NT-proBNP (from 2140 ± 1743 pg/ml to 863 ± 836 pg/ml; p = .02). In nonischemic DCM, diastolic dysfunction appears to correlate with areas of myocardial scar and hibernation. Transendocardial CD34+ cell transplantation may improve diastolic parameters in this patient cohort. Stem Cells Translational Medicine 2017;6:1515-1521.

Imaging and 1-day kinetics of intracoronary stem cell transplantation in patients with idiopathic dilated cardiomyopathy.

BACKGROUND: Stem cell transplantation is an emerging method of treatment for patients with cardiovascular disease. There are few studies completed or ongoing on stem cell therapy in patients with idiopathic dilated cardiomyopathy (IDCM). Information on stem cell homing and distribution in the myocardium after transplantation might provide important insight into effectiveness of transplantation procedure. AIM: To assess early engraftment, retention and migration of intracoronarily transplanted stem cells in the myocardium of patients with advanced dilated cardiomyopathy of non-ischaemic origin using stem cell labeling with (99m)Tc-exametazime (HMPAO). MATERIALS, METHODS: Thirty-five patients with IDCM and advanced heart failure were included in the study. Autologous hematopoietic (CD34+) stem cells were harvested by peripheral blood apheresis after bone marrow stimulation, labeled with (99m)Tc-HMPAO, tested for viability and injected into coronary vessel supplying areas of myocardium selected by myocardial perfusion scintigraphy as dysfunctional yet viable. Imaging was performed 1h and 18h after transplantation. RESULTS: Myocardial stem cell retention ranged from 0 to 1.44% on early and 0-0.97% on delayed imaging. Significant efflux of stem cells occurred from site of delivery in this time period (p<0.001). Stem cell viability was not affected by labeling. CONCLUSION: Stem cell labeling with (99m)Tc-HMPAO is a feasible method for stem cell tracking after transplantation in patients with IDCM.

Efficacy of CD34+ Stem Cell Therapy in Nonischemic Dilated Cardiomyopathy Is Absent in Patients With Diabetes but Preserved in Patients With Insulin Resistance.

UNLABELLED: We evaluated the association of diabetes and insulin resistance with the response to cell therapy in patients with nonischemic dilated cardiomyopathy (DCM). A total of 45 outpatients with DCM received granulocyte colony-stimulating factor for 5 days. CD34(+) cells were then collected by apheresis and injected transendocardially. Twelve patients had diabetes mellitus (DM group), 17 had insulin resistance (IR group), and 16 displayed normal glucose metabolism (no-IR group). After stimulation, we found higher numbers of CD34(+) cells in the IR group (94 ± 73 × 10(6) cells per liter) than in the no-IR group (54 ± 35 × 10(6) cells per liter) or DM group (31 ± 20 × 10(6) cells per liter; p = .005). Similarly, apheresis yielded the highest numbers of CD34(+) cells in the IR group (IR group, 216 ± 110 × 10(6) cells; no-IR group, 127 ± 82 × 10(6) cells; DM group, 77 ± 83 × 10(6) cells; p = .002). Six months after cell therapy, we found an increase in left ventricular ejection fraction in the IR group (+5.6% ± 6.9%) and the no-IR group (+4.4% ± 7.2%) but not in the DM group (-0.9% ± 5.4%; p = .035). The N-terminal pro-brain natriuretic peptide levels decreased in the IR and no-IR groups, but not in the DM group (-606 ± 850 pg/ml; -698 ± 1,105 pg/ml; and +238 ± 963 pg/ml, respectively; p = .034). Transendocardial CD34(+) cell therapy appears to be ineffective in DCM patients with diabetes. IR was associated with improved CD34(+) stem cell mobilization and a preserved clinical response to cell therapy. SIGNIFICANCE: The present study is the first clinical study directly evaluating the effects of altered glucose metabolism on the efficacy of CD34(+) stem cell therapy in patients with nonischemic dilated cardiomyopathy. The results offer critical insights into the physiology of stem cell mobilization in heart failure and possibly an explanation for the often conflicting results obtained with stem cell therapy for heart failure. These results demonstrate that patients with dilated cardiomyopathy and diabetes do not benefit from autologous CD34(+) cell therapy. This finding could serve as a useful tool when selecting heart failure patients for future clinical studies in the field of stem cell therapy.

Development and bioevaluation of nanofibers with blood-derived growth factors for dermal wound healing.

The aim of our work was to produce a modern nanomaterial with incorporated blood-derived growth factors, produced by electrospinning, applicable in treatment of chronic wounds. Platelet-rich plasma was chosen as a natural source of growth factors. Results showed that platelet-rich plasma stimulates keratinocyte and fibroblast cell growth in vitro. Its optimal concentration in growth medium was 2% (v/v) for both types of skin cells, while higher concentrations caused alterations in cell morphology, with reduced cell mobility and proliferation. In the next step hydrophilic nanofibers loaded with platelet-rich plasma were produced from chitosan and poly(ethylene oxide), using electrospinning. The morphology of nanofibers was stable in aqueous conditions for 72 h. It was shown that electrospinning does not adversely affect the biological activity of platelet-rich plasma. The effects of nanofibers with incorporated platelet-rich plasma on cell proliferation, survival, morphology and mobility were examined. Nanofibers limited cell mobility, changed morphology and stimulated cell proliferation. Despite of the small amount of blood-derived growth factors introduced in cell culture via platelet-rich plasma-loaded nanofibers, such nanofibrillar support significantly induced cell proliferation, indicating synergistic effect of nanotopography and incorporated growth factors. The overall results confirm favorable in vitro properties of produced nanofibers, indicating their high potential as a nanomaterial suitable for delivery of platelet-rich plasma in wound healing applications.

Effects of transendocardial CD34+ cell transplantation in patients with ischemic cardiomyopathy.

BACKGROUND: We investigated the effects of transendocardial CD34(+) cell transplantation in patients with ischemic cardiomyopathy. METHODS AND RESULTS: In a prospective crossover study, we enrolled 33 patients with ischemic cardiomyopathy with New York Heart Association class III and left ventricular ejection fraction <40%. In phase 1, patients were treated with medical therapy for 6 months. Thereafter, all patients underwent transendocardial CD34(+) cell transplantation. Peripheral blood CD34(+) cells were mobilized by granulocyte colony stimulating factor, collected via apheresis, and injected transendocardially in the areas of hibernating myocardium. Patients were followed up for 6 months after the procedure (phase 2). Two patients died during phase 1 and none during phase 2. The remaining 31 patients were 85% men, aged 57±6 years. In phase 1, we found no change in left ventricular ejection fraction (from 25.2±6.2% to 27.1±6.6%; P=0.23), N-terminal pro B-type natriuretic peptide (from 3322±3411 to 3672±5165 pg/mL; P=0.75) or 6-minute walk distance (from 373±68 to 411±116 m; P=0.17). In contrast, in phase 2 there was an improvement in left ventricular ejection fraction (from 27.1±6.6% to 34.9±10.9%; P=0.001), increase in 6-minute walk distance (from 411±116 to 496±113 m; P=0.001), and a decrease in N-terminal pro B-type natriuretic peptide (from 3672±5165 to 1488±1847 pg/mL; P=0.04). The average number of injected CD34(+) cells was 90.6±7.5×10(6). Higher doses of CD34(+) cells and a more diffuse distribution of transendocardial cell injections were associated with better clinical response. CONCLUSIONS: Transendocardial CD34(+) cell transplantation may be associated with improved left ventricular function, decreased N-terminal pro B-type natriuretic peptide levels, and better exercise capacity in patients with ischemic cardiomyopathy. These effects seem to be particularly pronounced in patients receiving diffusely distributed cell injections and high-dose cell therapy. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique identifier: NCT01350310.