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1.  Liver as a Source for Thymidine Phosphorylase Replacement in Mitochondrial Neurogastrointestinal Encephalomyopathy 
PLoS ONE  2014;9(5):e96692.
Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is a rare autosomal recessive mitochondrial disease associated with mutations in the nuclear TYMP gene. As a result, the thymidine phosphorylase (TP) enzyme activity is markedly reduced leading to toxic accumulation of thymidine and therefore altered mitochondrial DNA. MNGIE is characterized by severe gastrointestinal dysmotility, neurological impairment, reduced life expectancy and poor quality of life. There are limited therapeutic options for MNGIE. In the attempt to restore TP activity, allogenic hematopoietic stem cell transplantation has been used as cellular source of TP. The results of this approach on ∼20 MNGIE patients showed gastrointestinal and neurological improvement, although the 5-year mortality rate is about 70%. In this study we tested whether the liver may serve as an alternative source of TP. We investigated 11 patients (7M; 35–55 years) who underwent hepatic resection for focal disorders. Margins of normal liver tissue were processed to identify, quantify and localize the TP protein by Western Blot, ELISA, and immunohistochemistry, and to evaluate TYMP mRNA expression by qPCR. Western Blot identified TP in liver with a TP/GAPDH ratio of 0.9±0.5. ELISA estimated TP content as 0.5±0.07 ng/μg of total protein. TP was identified in both nuclei and cytoplasm of hepatocytes and sinusoidal lining cells. Finally, TYMP mRNA was expressed in the liver. Overall, our study demonstrates that the liver is an important source of TP. Orthotopic liver transplantation may be considered as a therapeutic alternative for MNGIE patients.
PMCID: PMC4011889  PMID: 24802030
2.  Medullospheres from DAOY, UW228 and ONS-76 Cells: Increased Stem Cell Population and Proteomic Modifications 
PLoS ONE  2013;8(5):e63748.
Medulloblastoma (MB) is an aggressive pediatric tumor of the Central Nervous System (CNS) usually treated according to a refined risk stratification. The study of cancer stem cells (CSC) in MB is a promising approach aimed at finding new treatment strategies.
Methodology/Principal Findings
The CSC compartment was studied in three characterized MB cell lines (DAOY, UW228 and ONS-76) grown in standard adhesion as well as being grown as spheres, which enables expansion of the CSC population. MB cell lines, grown in adherence and as spheres, were subjected to morphologic analysis at the light and electron microscopic level, as well as cytofluorimetric determinations. Medullospheres (MBS) were shown to express increasingly immature features, along with the stem cells markers: CD133, Nestin and β-catenin. Proteomic analysis highlighted the differences between MB cell lines, demonstrating a unique protein profile for each cell line, and minor differences when grown as spheres. In MBS, MALDI-TOF also identified some proteins, that have been linked to tumor progression and resistance, such as Nucleophosmin (NPM). In addition, immunocytochemistry detected Sox-2 as a stemness marker of MBS, as well as confirming high NPM expression.
Culture conditioning based on low attachment flasks and specialized medium may provide new data on the staminal compartment of CNS tumors, although a proteomic profile of CSC is still elusive for MB.
PMCID: PMC3663798  PMID: 23717474
3.  Response of human chondrocytes and mesenchymal stromal cells to a decellularized human dermis 
Although progress has been made in the treatment of articular cartilage lesions, they are still a major challenge because current techniques do not provide satisfactory long-term outcomes. Tissue engineering and the use of functional biomaterials might be an alternative regenerative strategy and fulfill clinical needs. Decellularized extracellular matrices have generated interest as functional biologic scaffolds, but there are few studies on cartilage regeneration. The aim of this study was to evaluate in vitro the biological influence of a newly developed decellularized human dermal extracellular matrix on two human primary cultures.
Normal human articular chondrocytes (NHAC-kn) and human mesenchymal stromal cells (hMSC) from healthy donors were seeded in polystyrene wells as controls (CTR), and on decellularized human dermis batches (HDM_derm) for 7 and 14 days. Cellular proliferation and differentiation, and anabolic and catabolic synthetic activity were quantified at each experimental time. Histology and scanning electron microscopy were used to evaluate morphology and ultrastructure.
Both cell cultures had a similar proliferation rate that increased significantly (p < 0.0005) at 14 days. In comparison with CTR, at 14 days NHAC-kn enhanced procollagen type II (CPII, p < 0.05) and aggrecan synthesis (p < 0.0005), whereas hMSC significantly enhanced aggrecan synthesis (p < 0.0005) and transforming growth factor-beta1 release (TGF-β1, p < 0.0005) at both experimental times. Neither inflammatory stimulus nor catabolic activity induction was observed. By comparing data of the two primary cells, NHAC-kn synthesized significantly more CPII than did hMSC at both experimental times (p < 0.005), whereas hMSC synthesized more aggrecan at 7 days (p < 0.005) and TGF-β1 at both experimental times than did NHAC-kn (p < 0.005).
The results obtained showed that in in vitro conditions HDM_derm behaves as a suitable scaffold for the growth of both well-differentiated chondrocytes and undifferentiated mesenchymal cells, thus ensuring a biocompatible and bioactive substrate. Further studies are mandatory to test the use of HDM_derm with tissue engineering to assess its therapeutic and functional effectiveness in cartilage regeneration.
PMCID: PMC3547812  PMID: 23294867
Articular chondrocytes; Mesenchymal bone marrow stromal cells; Decellularized dermis; Bioactivity; In vitro study; Cartilage tissue engineering
4.  The empowerment of translational research: lessons from laminopathies 
The need for a collaborative approach to complex inherited diseases collectively referred to as laminopathies, encouraged Italian researchers, geneticists, physicians and patients to join in the Italian Network for Laminopathies, in 2009. Here, we highlight the advantages and added value of such a multidisciplinary effort to understand pathogenesis, clinical aspects and try to find a cure for Emery-Dreifuss muscular dystrophy, Mandibuloacral dysplasia, Hutchinson-Gilford Progeria and forms of lamin-linked cardiomyopathy, neuropathy and lipodystrophy.
PMCID: PMC3458975  PMID: 22691392
Laminopathies; Emery-Dreifuss Muscular Dystrophy; Dilated Cardiomyopathy with Conduction Defects; Mandibuloacral Dysplasia; Familial Partial Lipodystrophy Type 2; Hutchinson-Gilford Progeria Syndrome; Rare Diseases; Networking activity; interdisciplinary approach to diseases
5.  Differentiation of Mesenchymal Stem Cells Derived from Pancreatic Islets and Bone Marrow into Islet-Like Cell Phenotype 
PLoS ONE  2011;6(12):e28175.
Regarding regenerative medicine for diabetes, accessible sources of Mesenchymal Stem Cells (MSCs) for induction of insular beta cell differentiation may be as important as mastering the differentiation process itself.
Methodology/Principal Findings
In the present work, stem cells from pancreatic islets (human islet-mesenchymal stem cells, HI-MSCs) and from human bone marrow (bone marrow mesenchymal stem cells, BM-MSCs) were cultured in custom-made serum-free medium, using suitable conditions in order to induce differentiation into Islet-like Cells (ILCs). HI-MSCs and BM-MSCs were positive for the MSC markers CD105, CD73, CD90, CD29. Following this induction, HI-MSC and BM-MSC formed evident islet-like structures in the culture flasks. To investigate functional modifications after induction to ILCs, ultrastructural analysis and immunofluorescence were performed. PDX1 (pancreatic duodenal homeobox gene-1), insulin, C peptide and Glut-2 were detected in HI-ILCs whereas BM-ILCs only expressed Glut-2 and insulin. Insulin was also detected in the culture medium following glucose stimulation, confirming an initial differentiation that resulted in glucose-sensitive endocrine secretion. In order to identify proteins that were modified following differentiation from basal MSC (HI-MSCs and BM-MSCs) to their HI-ILCs and BM-ILCs counterparts, proteomic analysis was performed. Three new proteins (APOA1, ATL2 and SODM) were present in both ILC types, while other detected proteins were verified to be unique to the single individual differentiated cells lines. Hierarchical analysis underscored the limited similarities between HI-MSCs and BM-MSCs after induction of differentiation, and the persistence of relevant differences related to cells of different origin.
Proteomic analysis highlighted differences in the MSCs according to site of origin, reflecting spontaneous differentiation and commitment. A more detailed understanding of protein assets may provide insights required to master the differentiation process of HI-MSCs to functional beta cells based only upon culture conditioning. These findings may open new strategies for the clinical use of BM-MSCs in diabetes.
PMCID: PMC3241623  PMID: 22194812
6.  Esophageal cell proliferation in gastroesophageal reflux disease: Clinical-morphological data before and after pantoprazole 
AIM: To evaluate esophageal mucosal defense mechanisms at an epithelial level to establish if pantoprazole treatment can induce ultrastructural healing and improvement in the proliferation activity of the esophageal epithelium in gastroesophageal reflux disease (GERD).
METHODS: This was a single-blinded study for pH-monitoring, and histological, ultrastructural and MIB1 immunostaining evaluation. Fifty eight patients with GERD were enrolled and underwent 24 h pH-monitoring and endoscopy. Patients were treated for 12 and 24 mo with pantoprazole. Esophageal specimens were taken for histological and ultrastructural evaluation, before and after the treatment.
RESULTS: With transmission electron microscopy, all patients with GERD showed ultrastructural signs of damage with dilation of intercellular spaces (DIS). After 3 mo of therapy the mean DIS values showed a significant reduction and the mean MIB1-LI values of GERD showed an increase in cell proliferation. A further 3 mo of therapy significantly increased cell proliferation only in the erosive esophagitis (ERD) group.
CONCLUSION: Three months of pantoprazole therapy induced ultrastructural healing of mucosal damage in 89% and 93% of ERD and non-erosion patients, respectively. Moreover, long-term pantoprazole treatment may be helpful in increasing the capability for esophageal cell proliferation in GERD, particularly in ERD patients.
PMCID: PMC2653394  PMID: 19248192
Gastroesophageal reflux disease; Esophagitis; Cell proliferation; Electron microscopy; Pantoprazole
7.  Effect of omeprazole on symptoms and ultrastructural esophageal damage in acid bile reflux 
AIM: To value whether omeprazole could induce the healing of DIS and regression of symptoms in patients with DGER.
METHODS: We enrolled 15 symptomatic patients with a pathological esophageal 24-h pH-metry and bilimetry. Patients underwent endoscopy and biopsies were taken from the distal esophagus. Specimens were analyzed at histology and transmission electron microscopy (TEM). Patients were treated with omeprazole 40 mg/d for 3 mo and then endoscopy with biopsies was repeated. Patients with persistent heartburn and/or with an incomplete recovery of DIS were treated for 3 more months and endoscopy with biopsies was performed.
RESULTS: Nine patients had a non-erosive reflux disease at endoscopy (NERD) while 6 had erosive esophagitis (ERD). At histology, of the 6 patients with erosive esophagitis, 5 had mild esophagitis and 1 moderate esophagitis. No patients with NERD showed histological signs of esophagitis. After 3 mo of therapy, 13/15 patients (86.7%, P<0.01) showed a complete recovery of DIS and disappearance of heartburn. Of the 2 patients treated for 3 more months, complete recovery of DIS and heartburn were achieved in one.
CONCLUSION: Three or 6 mo of omeprazole therapy led to a complete regression of the ultrastructural esophageal damage in 86.7% and in 93% of patients with DGER, NERD and ERD respectively. The ultrastructural recovery of the epithelium was accompanied by regression of heartburn in all cases.
PMCID: PMC4305895  PMID: 15793885
Duodenogastroesophageal reflux; Gastroeso-phageal reflux disease; Transmission Electron Microscopy; Dilated Intercellular Spaces; Non-erosive reflux disease

Results 1-7 (7)