Ticiana Ferreira Larocca

Safety and neurological assessments after autologous transplantation of bone marrow mesenchymal stem cells in subjects with chronic spinal cord injury.

IntroductionThe administration of stem cells holds promise as a potential therapy for spinal cord injury (SCI). Mesenchymal stem cells have advantages for clinical applications, since they can be easily obtained, are suitable for autologous transplantation and have been previously shown to induce regeneration of the spinal cord in experimental settings. Here we evaluated the feasibility, safety and potential efficacy of autologous transplantation of mesenchymal stem cells in subjects with chronic complete SCI.MethodWe conducted a phase I, non-controlled study in 14 subjects of both genders aging between 18 to 65 years, with chronic traumatic SCI (>6 months), at thoracic or lumbar levels, classified as American Spinal Injury Association (ASIA) A - complete injury. Baseline somatosensory evoked potentials (SSEP), spinal magnetic resonance imaging (MRI) and urodynamics were assessed before and after treatment. Pain rating was performed using the McGill Pain Questionnaire and a visual analogue score scale. Bone marrow-derived mesenchymal stem cells were cultured and characterized by flow cytometry, cell differentiation assays and G-band karyotyping. Mesenchymal stem cells were injected directly into the lesion following laminectomy and durotomy.ResultsCell transplantation was an overall safe and well-tolerated procedure. All subjects displayed variable improvements in tactile sensitivity and eight subjects developed lower limbs motor functional gains, principally in the hip flexors. Seven subjects presented sacral sparing and improved American Spinal Injury Association impairment scale (AIS) grades to B or C – incomplete injury. Nine subjects had improvements in urologic function. One subject presented changes in SSEP 3 and 6 months after mesenchymal stem cells transplantation. Statistically significant correlations between the improvements in neurological function and both injury size and level were found.ConclusionIntralesional transplantation of autologous mesenchymal stem cells in subjects with chronic, complete spinal cord injury is safe, feasible, and may promote neurological improvements.Trial registrationClinicalTrials.gov NCT01325103 – Registered 28 March 2011

Transplantation of adipose tissue mesenchymal stem cells in experimental chronic chagasic cardiopathy.

BACKGROUND Chagas disease, caused by the protozoan Trypanosoma cruzi, is a major cause of heart failure in Latin America. Tissue therapy has been investigated as a possible therapeutic option for patients with cardiovascular disease. OBJECTIVE This study evaluated the effects of therapy with mesenchymal stem cells in an experimental model of chronic Chagasic cardiomyopathy. METHODS C57BL/6 mice were infected with 1000 trypomastigotes from the Colombian strain of T. cruzi and, after six months of infection, were treated with mesenchymal human stem cells from adipose tissue (STAT) or with Dulbecco/Vogt modified Eagles minimal essential medium - DMEM (control). The treated group received two intraperitoneal injections of STAT (1x10(6) cells/dose), with a month interval between the two doses. Before and after the first and second months of treatment, the chagasic and normal control animals underwent cardiopulmonary exercise testing and electrocardiography. All animals were sacrificed under anesthesia after two months of treatment for histopathological analysis of the heart. RESULTS No improvement was observed in arrhythmias and cardiovascular function in the group of animals treated with STAT; however, sections of mice hearts in this group revealed a significant reduction in the number of inflammatory cells (p<0.0001) and areas of fibrosis (p<0.01) in comparison with chagasic animals treated with DMEM. CONCLUSION Thus, it is concluded that administration of intraperitoneal STAT can reduce inflammation and fibrosis in the heart of mice chronically infected with T. cruzi; however, there were no effects on the cardiac function two months after transplantation.

Evaluation of Galectin-3 as a Novel Biomarker for Chagas Cardiomyopathy

Objectives: Chagas cardiomyopathy has worse long-term outcomes than other cardiomyopathies. A biomarker strategy to refer subjects for noninvasive cardiac imaging may help in the early identification of cardiac damage in subjects with Chagas disease. Galectin-3 (Gal-3) is a mediator of cardiac fibrosis shown to be upregulated in animal models of decompensated heart failure. Here we assessed the correlation of Gal-3 with myocardial fibrosis in patients with Chagas disease. Methods: This study comprised 61 subjects with Chagas disease. All subjects underwent clinical assessments, Doppler echocardiography and magnetic resonance imaging. Plasmatic Gal-3 was determined by ELISA. Results: Delayed enhancement (DE) was identified in 37 of 61 subjects (64%). The total amount of myocardial fibrosis was 9.4% [interquartile interval (IQI): 2.4-18.4]. No differences were observed in Gal-3 concentration according to the presence or absence of myocardial fibrosis, with a median Gal-3 concentration of 11.7 ng/ml (IQI: 9.4-15) in subjects with DE versus 12.9 ng/ml (IQI: 9.2-14) in subjects without DE (p = 0.18). No correlation was found between myocardial fibrosis and Gal-3 concentration (r = 0.098; p = 0.47). Conclusions: There is no correlation between the degree of myocardial fibrosis and the concentration of Gal-3 in subjects with Chagas disease.

Assessment of Galectin-3 Polymorphism in Subjects with Chronic Chagas Disease.

Background Galectin-3, a β-galactoside binding lectin, has been described as a mediator of cardiac fibrosis in experimental studies and as a risk factor associated with cardiovascular events in subjects with heart failure. Previous studies have evaluated the genetic susceptibility to Chagas disease in humans, including the polymorphisms of cytokine genes, demonstrating correlations between the genetic polymorphism and cardiomyopathy development in the chronic phase. However, the relationship between the galectin-3 single nucleotide polymorphism (SNP) and phenotypic variations in Chagas disease has not been evaluated. Objective The present study aimed to determine whether genetic polymorphisms of galectin-3 may predispose to the development of cardiac forms of Chagas disease. Methods Fifty-five subjects with Chagas disease were enrolled in this observational study. Real-time polymerase chain reaction (PCR) was used for genotyping the variants rs4644 and rs4652 of the galectin-3 gene. Results For the SNP rs4644, the relative risk for the cardiac form was not associated with the genotypes AA (OR = 0.79, p = 0.759), AC (OR = 4.38, p = 0.058), or CC (OR = 0.39, p = 0.127). Similarly, for the SNP rs4652, no association was found between the genotypes AA (OR = 0.64, p = 0.571), AC (OR = 2.85, p = 0.105), or CC (OR = 0.49, p = 0.227) and the cardiac form of the disease. Conclusion Our results showed no association between the different genotypes for both SNPs of the galectin-3 gene and the cardiac form of Chagas disease.

Lack of association between serum syndecan-4, myocardial fibrosis and ventricular dysfunction in subjects with chronic Chagas disease

Background Syndecan-4 is a transmembrane glycoprotein associated with inflammation and fibrosis. Increased syndecan-4 levels were previously detected after acute myocardial infarction and in subjects with heart failure. However, the levels of syndecan-4 in subjects with Chagas disease have not so far been investigated. The aim of this study was to investigate the potential role of serum sydencan-4 as a novel biomarker for myocardial fibrosis and cardiac dysfunction in subjects with Chagas disease. Methods This study comprised subjects with Chagas disease (n = 56), being 14 (25%) with the indeterminate form, 16 (29%) with the cardiac form without ventricular dysfunction, and 26 (46%) with the cardiac form with ventricular dysfunction. Results Syndecan-4 serum concentrations did not correlate with presence or absence of myocardial fibrosis (P = 0.386) nor disease severity in subjects with Chagas disease (P = 0.918). Additionally, no correlation was found either between the degree of myocardial fibrosis and serum syndecan-4 [r = 0.08; P = 0.567] or between left ventricular ejection fraction and syndecan-4 [r = 0.02; P = 0.864]. In contrast, NT-proBNP levels correlated with ejection fraction and myocardial fibrosis. Conclusions Our results demonstrate the lack of correlations between serum syndecan-4, myocardial fibrosis and cardiac dysfunction in subjects with Chagas disease. Further studies are required to show if syndecan-4 concentrations can be marker for prognosis assessment or disease progression.

Transplantation of autologous bone marrow stem cells in patients with chronic spinal cord injury

Stem cells are being investigated by their potential use in regenerative medicine. There is currently a lack of effective clinical therapy for a number conditions, such as severe spinal cord injury (SCI). SCI can lead to chronic paraplegia, considered an irreversible condition. The administration of stem cells has been tested as a potential therapy for SCI. In the present study we evaluated the feasibility, safety and potential efficacy of autologous mesenchymal stem cells (MSC) transplantation in patients with chronic complete SCI. We conducted a phase I/II, non-controlled study in 14 patients of both genders aging between 18-65 years, with ASIA A classified chronic traumatic SCI. Baseline somatosensory evoked potentials (SSEP), spinal magnetic resonance imaging (MRI) and urodynamics were assessed before and after treatment. Pain rating was performed using the McGill Pain Questionnaire and a visual analogue score scale. Bone marrow-derived MSC were cultured and characterized by flow cytometry, cell differentiation assays and G-band karyotyping, showing morphological and phenotypic characteristics of MSC, as well as genetic stability. MSC were injected directly into the lesion following laminectomy and durotomy. Transplantation of bone marrow derived MSC was an overall safe procedure. All of the patients were discharged within 48 hours after surgery. Only one patient developed a post-operatory complication, evolving a liquoric fistula that was treated by an additional surgical procedure. Nine patients had improvements in urologic function. All patients displayed variable improvements in sensitivity and 8 patients developed lower limbs motor functional gains, principally in the hip flexors. All patients had variable improvements in ASIA global scores. Additionally, 6 patients had changes in the AIS score to grade B and one to grade C. A direct correlation between motor gain and lesion level and an inverse correlation between light touch gain and lesion volume were found 6 months after transplantation. One patient presented changes in SSEP 3 and 6 months after MSC transplantation. Although there is an abundance of studies describing the natural history of neurologic functional gains during the first year post-SCI, there is a lack of data regarding the degree of neurological recovery that may naturally occur during prolonged follow up investigation. In the present study, we enrolled only patients with chronic and complete spinal cord injury (ASIA A) whom had previously been subjected to decompressive surgery and lengthy rehabilitation protocols without acquiring significant motor or sensory gains. Although this was not a controlled study, based on the patient profiles and the expected spontaneous gains, our study showed potential benefits of MSC transplantation treatment, in variable degrees of motor and sensory improvements, clinical pain measures and urodynamics parameters. The use of MSC presents several advantages, such as isolation from bone marrow aspirates and large-scale expansion in cell culture procedures, which are feasible to be performed in autologous transplantations. We conclude that intralesional transplantation of autologous MSC in spinal cord injury patients is safe and feasible, and may provide some progressive benefits. We are currently beginning new clinical trials based on MSC therapy for SCI.

Assessment of syndecan-4 expression in the hearts of Trypanosoma cruzi-infected mice and human subjects with chronic Chagas disease cardiomyopathy

BackgroundChronic Chagas cardiomyopathy (CCC) is characterized by the presence of a multifocal inflammatory response and myocardial damage, leading to fibrosis, arrhythmias and ventricular dysfunction. The expression of syndecan-4, a transmembrane proteoglycan, was previously found to be increased in the hearts of mice chronically infected with Trypanosoma cruzi. The possible involvement of syndecan-4 in the disease pathogenesis, however, remains unknown. Here we evaluated the pattern of expression of syndecan-4 in the heart tissue of T. cruzi infected mice and subjects with Chagas cardiomyopathy, correlating with the degree of inflammation and fibrosis.MethodsThe expression of syndecan-4 was evaluated by immunofluorescence and RT-qPCR in the hearts of C57Bl/6 mice at different time points after infection with the Colombian strain of T. cruzi. Immunostainings for syndecan-4 were performed in heart samples obtained from CCC patients and other etiologies of heart failure. The number of infiltrating inflammatory cells and area of fibrosis were also evaluated and quantified.ResultsIn the experimental model, the number of infiltrating inflammatory cells and fibrosis area in the hearts progressively increased after the acute phase of infection, while syndecan-4 expression remained elevated in similar levels in both the acute and chronic phases. Confocal microscopy analysis demonstrated the localization of syndecan-4 expression in blood vessels, co-localized with α-SMA, a marker for vascular smooth muscle cells (VSMCs). Confocal microscopy analysis of human hearts samples showed a similar pattern of syndecan-4 expression in blood vessels. No correlation between syndecan-4 expression and inflammation or fibrosis was found in the hearts from subjects with CCC. We also compared the expression of syndecan-4 evaluated in subjects with CCC, idiopathic dilated cardiomyopathy and ischemic cardiomyopathy. No differences in the number of syndecan-4 positive vessels/mm2 were found comparing the three groups (P = 0.466), whereas CCC patients presented a higher number of infiltrating inflammatory cells, compared to the other etiologies of heart failure. Additionally, no correlation between syndecan-4 and fibrosis or numbers of inflammatory cells was found.ConclusionsSyndecan-4 is expressed in the heart during the acute and chronic phases of Chagas disease, in association with VSMCs, independently of the degree of myocardial fibrosis or the number of infiltrating inflammatory cells.

The Presence and Extension of Myocardial Fibrosis in the Undetermined Form of Chagas’ Disease: A Study Using Magnetic Resonance

Background Previous data has shown that patients in the indeterminate form of Chagas disease may present myocardial fibrosis as shown on through magnetic resonance imaging (MRI). However, there is little information available regarding the degree of severity of myocardial fibrosis in these individuals. This variable has the potential to predict the evolution of Chagas’ disease into its cardiac form. Objectives To describe the frequency and extent of myocardial fibrosis evaluated using an MRI in patients in the indeterminate form, and to compare it with other forms of the disease. Methods Patients were admitted one after another. Their clinical history was collected and they were submitted to laboratory exams and an MRI. Results Sixty-one patients with Chagas’ disease, with an average age of 58 ± 9 years old, 17 patients in the indeterminate form, 16 in the cardiac form without left ventricular (LV) dysfunction and 28 in the cardiac form with LV dysfunction were studied. P <0.05 was considered to be statistically significant. Late enhancement was detected in 37 patients (64%). Myocardial fibrosis was identified in 6 individuals in indeterminate form (41%; 95% CI 23-66) in a proportion similar to that observed in cardiac form without LV dysfunction (44%); p = 1.0. Among the individuals with fibrosis, the total area of the affected myocardium was 4.1% (IIQ: 2.1 - 10.7) in the indeterminate form versus 2.3% (IIQ: 1-5) in the cardiac form without LV (p = 0.18). The left ventricular fraction ejection in subjects in the indeterminate form was similar to that of the individuals in the cardiac form without ventricular dysfunction (p = 0.09). Conclusion The presence of fibrosis in the indeterminate form of Chagas’ disease has a frequency and extension similar to that of in the cardiac form without dysfunction, suggesting that the former is part of a subclinical disease spectrum, rather than lacking cardiac involvement.

Image-guided percutaneous intralesional administration of mesenchymal stromal cells in subjects with chronic complete spinal cord injury: a pilot study

BACKGROUND AIMS The potential of cell therapies to improve neurological function in subjects with spinal cord injury (SCI) is currently under investigation. In this context, the choice of cell type, dose, route and administration regimen are key factors. Mesenchymal stromal cells (MSCs) can be easily obtained, expanded and are suitable for autologous transplantation. Here we conducted a pilot study that evaluated safety, feasibility and potential efficacy of intralesional MSCs transplantation performed through image-guided percutaneous injection, in subjects with chronic complete SCI. METHODS Five subjects with chronic traumatic SCI (>6 months), at thoracic level, classified as American Spinal Cord Injury Association impairment scale (AIS) grade A, complete injury, were included. Somatosensory evoked potentials (SSEP), spinal magnetic resonance imaging (MRI) and urodynamics were assessed before and after treatment. Autologous MSCs were injected directly into the lesion site through percutaneous injection guided by computerized tomography (CT). RESULTS Tomography-guided percutaneous cell transplantation was a safe procedure without adverse effects. All subjects displayed improvements in spinal cord independence measure (SCIM) scores and functional independence measure (FIM), mainly due to improvements in bowel movements and regularity. Three subjects showed improved sensitivity to tactile stimulation. Two subjects improved AIS grade to B, incomplete injury, although this was sustained in only one of them during the study follow-up. CONCLUSION Autologous bone marrow MSC transplantation, performed through CT-guided percutaneous injection, was shown to be safe and feasible. Further studies are required to demonstrate efficacy of this therapeutic scheme.

Optimization of oncological 18F‐FDG PET/CT imaging based on a multiparameter analysis

PURPOSE This paper describes a method to achieve consistent clinical image quality in (18)F-FDG scans accounting for patient habitus, dose regimen, image acquisition, and processing techniques. METHODS Oncological PET/CT scan data for 58 subjects were evaluated retrospectively to derive analytical curves that predict image quality. Patient noise equivalent count rate and coefficient of variation (CV) were used as metrics in their analysis. Optimized acquisition protocols were identified and prospectively applied to 179 subjects. RESULTS The adoption of different schemes for three body mass ranges (<60 kg, 60-90 kg, >90 kg) allows improved image quality with both point spread function and ordered-subsets expectation maximization-3D reconstruction methods. The application of this methodology showed that CV improved significantly (p < 0.0001) in clinical practice. CONCLUSIONS Consistent oncological PET/CT image quality on a high-performance scanner was achieved from an analysis of the relations existing between dose regimen, patient habitus, acquisition, and processing techniques. The proposed methodology may be used by PET/CT centers to develop protocols to standardize PET/CT imaging procedures and achieve better patient management and cost-effective operations.