The aim of the present work was to explore mesenchymal stem cells (MSCs) differentiation potentia... more The aim of the present work was to explore mesenchymal stem cells (MSCs) differentiation potential towards neural phenotype. MSCs are self-renewable multipotent cells shown to be able to support hematopoiesis and to improve functional outcomes in animal models of neurological disorders. MSCs were obtained by plastic adherence from iliac crest bone marrow of healthy donors for allogeneic transplantation and, for the in vitro studies, were cultured on laminin-coated dishes in a B27 Neurobasal medium with 3% to 10% FBS for 3 weeks. Few cell (11%) showing bipolar morphologies, expressed β-tubulin III and GFAP. Furthermore, only GAP43 expression was detected by RT-PCR. Addition of exogenous neurotrophins to cultures did not improve neural differentiation. To investigate the brain microenvironment effect on MSCs, cells were cultured on brain sections and supernatant of the cultures analyzed by ELISA. In this condition, MSCs were shown to release soluble human NT3/NT4 and NGF and to expres...
Efficient delivery of cells to target tissues is a major problem in cell therapy. We report that ... more Efficient delivery of cells to target tissues is a major problem in cell therapy. We report that enhancing delivery of mesoangioblasts leads to a complete reconstitution of downstream skeletal muscles in a mouse model of severe muscular dystrophy (α-sarcoglycan ko). Mesoangioblasts, vessel-associated stem cells, were exposed to several cytokines, among which stromalderived factor (SDF) 1 or tumor necrosis factor (TNF) α were the most potent in enhancing transmigration in vitro and migration into dystrophic muscle in vivo. Transient
In animal models of neurological disorders for cerebral ischemia, Parkinson's disease, and sp... more In animal models of neurological disorders for cerebral ischemia, Parkinson's disease, and spinal cord lesions, transplantation of mesenchymal stem cells (MSCs) has been reported to improve functional outcome. Three mechanisms have been suggested for the effects of the MSCs: transdifferentiation of the grafted cells with replacement of degenerating neural cells, cell fusion, and neuroprotection of the dying cells. Here we demonstrate that a restricted number of cells with differentiated astroglial features can be obtained from human adult MSCs (hMSCs) both in vitro using different induction protocols and in vivo after transplantation into the developing mouse brain. We then examined the in vitro differentiation capacity of the hMSCs in coculture with slices of neonatal brain cortex. In this condition the hMSCs did not show any neuronal transdifferentiation but expressed neurotrophin low-affinity (NGFRp75) and high-affinity (trkC) receptors and released nerve growth factor (NGF) ...
... Abstract. Myogenic differentiation of galectin-1 pretreated human fetal mesenchymal stem cell... more ... Abstract. Myogenic differentiation of galectin-1 pretreated human fetal mesenchymal stem cells after intra-arterial injection into dystrophic mice / J. Chan, M. Gavina, M. Belicchi, Y. Torrente, JE Morgan, NM Fisk. - In: Atti del Congresso ...
Accumulation of unwanted/misfolded proteins in aggregates has been observed in airways of patient... more Accumulation of unwanted/misfolded proteins in aggregates has been observed in airways of patients with cystic fibrosis (CF), a life-threatening genetic disorder caused by mutations in the gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR). Here we show how the defective CFTR results in defective autophagy and decreases the clearance of aggresomes. Defective CFTR-induced upregulation of reactive oxygen species (ROS) and tissue transglutaminase (TG2) drive the crosslinking of beclin 1, leading to sequestration of phosphatidylinositol-3-kinase (PI(3)K) complex III and accumulation of p62, which regulates aggresome formation. Both CFTR knockdown and the overexpression of green fluorescent protein (GFP)-tagged-CFTR(F508del) induce beclin 1 downregulation and defective autophagy in non-CF airway epithelia through the ROS-TG2 pathway. Restoration of beclin 1 and autophagy by either beclin 1 overexpression, cystamine or antioxidants rescues the localization of the beclin 1 interactome to the endoplasmic reticulum and reverts the CF airway phenotype in vitro, in vivo in Scnn1b-transgenic and Cftr(F508del) homozygous mice, and in human CF nasal biopsies. Restoring beclin 1 or knocking down p62 rescued the trafficking of CFTR(F508del) to the cell surface. These data link the CFTR defect to autophagy deficiency, leading to the accumulation of protein aggregates and to lung inflammation.
Background information. Cell motility entails the reorganization of the cytoskeleton and membrane... more Background information. Cell motility entails the reorganization of the cytoskeleton and membrane trafficking for effective protrusion. The GIT-PIX protein complexes are involved in the regulation of cell motility and adhesion and in the endocytic traffic of members of the family of G-protein-coupled receptors. We have investigated the function of the endogenous GIT complexes in the regulation of cell motility stimulated by fMLP (formyl-Met-Leu-Phe) peptide, in a rat basophilic leukaemia RBL-2H3 cell line stably expressing an HA (haemagglutinin)-tagged receptor for the fMLP peptide. Results. Our analysis shows that RBL cells stably transfected with the chemoattractant receptor expressed both GIT1-PIX and GIT2-PIX endogenous complexes. We have used silencing of the different members of the complex by small interfering RNAs to study the effects on a number of events linked to agonist-induced cell migration. We found that cell adhesion was not affected by depletion of any of the proteins of the GIT complex, whereas agonist-enhanced cell spreading was inhibited. Analysis of agonist-stimulated haptotactic cell migration indicated a specific positive effect of GIT1 depletion on trans-well migration. The internalization of the formyl-peptide receptor was also inhibited by depletion of GIT1 and GIT2. The effects of the GIT complexes on trafficking of the receptors was confirmed by an antibody-enhanced agonist-induced internalization assay, showing that depletion of PIX, GIT1 or GIT2 protein caused decreased perinuclear accumulation of internalized receptors. Conclusions. Our results show that endogenous GIT complexes are involved in the regulation of chemoattractantinduced cell motility and receptor trafficking, and support previous findings indicating an important function of the GIT complexes in the regulation of different G-protein-coupled receptors. Our results also indicate that endogenous GIT1 and GIT2 regulate distinct subsets of agonist-induced responses and suggest a possible functional link between the control of receptor trafficking and the regulation of cell motility by GIT proteins.
Background: YKL-40 − a chitinase-like protein − was increased in patients with severe asthma and ... more Background: YKL-40 − a chitinase-like protein − was increased in patients with severe asthma and chronic obstructive pulmonary disease (COPD). Neutrophils secrete YKL-40. We hypothesized that increased YKL-40 levels in lung diseases reflect neutrophilic inflammation and that YKL-40 accumulates in the airways of cystic fibrosis patients (CF), a prototypic neutrophilic airway disease. We aimed to analyze YKL-40 levels in human and murine CF lung disease compared to COPD, asthma and control subjects. Methods: YKL-40 protein levels were measured in serum and sputum samples of CF, asthma, COPD and healthy individuals. Protein levels of the murine homologue BRP-39 were quantified in airway fluids from CF-like bENaC-Tg mice. Results: YKL-40 levels were significantly increased in human and murine CF airway fluids compared to asthma, COPD and healthy individuals. In both CF patients and bENaC-Tg mice, YKL-40/BRP-39 airway levels correlated with severity of obstructive lung disease. Conclusion: YKL-40 is increased in CF airway fluids and is negatively associated with pulmonary function. These findings suggest YKL-40 as potential biomarker and therapeutic target in CF lung disease.
Increasing evidence implicates both platelets and neutrophils in the formation, stabilization, an... more Increasing evidence implicates both platelets and neutrophils in the formation, stabilization, and growth of peripheral and coronary thrombi. Neutrophil extracellular traps (NETs) play a key role. The early events in the deregulated cross-talk between platelets and neutrophils are poorly characterized. To identify at the molecular level the mechanism through which platelets induce the generation of NETs in sterile conditions. The presence of NETs was determined in 26 thrombi from patients with acute myocardial infarction by immunohistochemistry and immunofluorescence and markers of NETs assessed in the plasma. In vitro NET generation was studied in static and in physiological flow conditions. Coronary thrombi mainly consist of activated platelets, neutrophils, and NETs in close proximity of platelets. Activated platelets commit neutrophils to NET generation. The event abates in the presence of competitive antagonists of the high mobility group box 1 (HMGB1) protein. Hmgb1(-/-) plate...
We have identified with molecular markers and purified by flow cytometry two populations of cells... more We have identified with molecular markers and purified by flow cytometry two populations of cells that are developmentally and anatomically related to blood vessel walls in human tissues: myoendothelial cells, found in skeletal muscle and coexpressing markers of endothelial and myogenic cells, and pericytes--aka mural cells--which surround endothelial cells in capillaries and microvessels. Purified myoendothelial cells and pericytes exhibit multilineage developmental potential and differentiate, in culture and in vivo, into skeletal myofibers, bone, cartilage, and adipocytes. Myoendothelial cells and pericytes can be cultured on the long term with sustained marker expression and differentiation potential and clonal populations thereof have been derived. Yet, these blood vessel wall-derived progenitors exhibit no tendency to malignant transformation upon extended culture. Our results suggest that multipotent progenitor cells, such as mesenchymal stem cells, previously isolated retrospectively from diverse cultured adult tissues are derived from a subset of perivascular cells. We present in this chapter the main strategies and tactics used to purify, culture on the long term, and phenotypically characterize these novel multipotent cells.
but only a cocktail including SCF, bFGF, EGF, VEGF, LIF, TEPA, IL6 showed a significant expansion... more but only a cocktail including SCF, bFGF, EGF, VEGF, LIF, TEPA, IL6 showed a significant expansion of stem cells in culture. In this condition we were able to expand the CD133+ cells for more than 50 passages over a 2-month period and we observed no indication of replicative senescence or significant changes in cellular division time during expansion period. Proliferating cells still had the capacity to form hematopoietic and endothelial colonies in semisolid media. Furthermore, we showed that expanded populations of CD133+ cells derived from blood maintain the capacity to differentiate into myogenic cells in vitro and in vivo. Human circulating CD133+ cells were also cultured at 5-or 20-percent oxygen in liquid culture in presence of the better cocktail of cytokines and we analysed and compared their expansion capacity and their vitality. The total number of cells increased 6-fold at 5-percent oxygen and could result in a better maintenance of the balance between primitive progenitor cell renewal and clonogenic progenitor expansion, thus representing a tool of remarkable therapeutic interest.
with also antioxidant properties, have beneficial effects in mdx mice. The drugs used are not ava... more with also antioxidant properties, have beneficial effects in mdx mice. The drugs used are not available for clinical studies. We tested whether genistein and flavocoxid, supplements with known antioxidant and antinflammatory properties readily available for clinical use, could have a beneficial effect on muscle function, morphology and biochemical pattern in mdx mice. Five-week old mdx mice received for five weeks either genistein (2 mg/kg i.p. daily), flavocoxid (5 mg/kg i.p. daily or vehicle; flavonoids treatment 1)'increased forelimb strength (p < 0.05) and strength normalized to weight (p < 0.05) and decreased fatigue (p < 0.05; 2) reduced serum creatine-kinase levels (p < 0.01; 3) increased GPX activity and reduced markers of oxidative stress (p < 0.05; 4) blunted NF-jB DNA-binding activity (p < 0.05; 5) reduces muscle necrosis (p < 0.01) and enhances regeneration (p < 0.05) with an augmented number of myogenin-positive satellite cells and myonuclei, and of developmental myosin heavy chainpositive fibers. Our results suggest that these flavonoids might have a beneficial effect on muscle function and morphology in mdx mice. Further studies are needed to investigate the biochemical substrates of such encouraging preliminary results taking into account that these supplements could be easily introduced in the daily diet of patients with DMD.
Background: Various prognostic serum and cellular markers have been identified for many diseases,... more Background: Various prognostic serum and cellular markers have been identified for many diseases, such as cardiovascular diseases and tumor pathologies. Here we assessed whether the levels of certain stem cells may predict the progression of Duchenne muscular dystrophy (DMD).
Perivascular multipotent mesenchymal progenitors exist in a variety of tissues, including the pla... more Perivascular multipotent mesenchymal progenitors exist in a variety of tissues, including the placenta. Here, we suggest that the abundant vasculature present in the human placenta can serve as a source of myogenic cells to regenerate skeletal muscle. Chorionic villi dissected from the mid-gestation human placenta were first transplanted intact into the gastrocnemius muscles of SCID=mdx mice, where they participated in muscle regeneration by producing myofibers expressing human dystrophin and spectrin. In vitro-cultured placental villi released rapidly adhering and migratory CD146+CD34ÀCD45ÀCD56À cells of putative perivascular origin that expressed mesenchymal stem cell markers. CD146+CD34ÀCD45ÀCD56À perivascular cells isolated and purified from the placental villi by flow cytometry were indeed highly myogenic in culture, and generated dystrophin-positive myofibers, and they promoted angiogenesis after transplantation into SCID=mdx mouse muscles. These observations confirm the existence of mesenchymal progenitor cells within the walls of human blood vessels, and suggest that the richly vascularized human placenta is an abundant source of perivascular myogenic cells able to migrate within dystrophic muscle and regenerate myofibers.
The aim of the present work was to explore mesenchymal stem cells (MSCs) differentiation potentia... more The aim of the present work was to explore mesenchymal stem cells (MSCs) differentiation potential towards neural phenotype. MSCs are self-renewable multipotent cells shown to be able to support hematopoiesis and to improve functional outcomes in animal models of neurological disorders. MSCs were obtained by plastic adherence from iliac crest bone marrow of healthy donors for allogeneic transplantation and, for the in vitro studies, were cultured on laminin-coated dishes in a B27 Neurobasal medium with 3% to 10% FBS for 3 weeks. Few cell (11%) showing bipolar morphologies, expressed β-tubulin III and GFAP. Furthermore, only GAP43 expression was detected by RT-PCR. Addition of exogenous neurotrophins to cultures did not improve neural differentiation. To investigate the brain microenvironment effect on MSCs, cells were cultured on brain sections and supernatant of the cultures analyzed by ELISA. In this condition, MSCs were shown to release soluble human NT3/NT4 and NGF and to expres...
Efficient delivery of cells to target tissues is a major problem in cell therapy. We report that ... more Efficient delivery of cells to target tissues is a major problem in cell therapy. We report that enhancing delivery of mesoangioblasts leads to a complete reconstitution of downstream skeletal muscles in a mouse model of severe muscular dystrophy (α-sarcoglycan ko). Mesoangioblasts, vessel-associated stem cells, were exposed to several cytokines, among which stromalderived factor (SDF) 1 or tumor necrosis factor (TNF) α were the most potent in enhancing transmigration in vitro and migration into dystrophic muscle in vivo. Transient
In animal models of neurological disorders for cerebral ischemia, Parkinson's disease, and sp... more In animal models of neurological disorders for cerebral ischemia, Parkinson's disease, and spinal cord lesions, transplantation of mesenchymal stem cells (MSCs) has been reported to improve functional outcome. Three mechanisms have been suggested for the effects of the MSCs: transdifferentiation of the grafted cells with replacement of degenerating neural cells, cell fusion, and neuroprotection of the dying cells. Here we demonstrate that a restricted number of cells with differentiated astroglial features can be obtained from human adult MSCs (hMSCs) both in vitro using different induction protocols and in vivo after transplantation into the developing mouse brain. We then examined the in vitro differentiation capacity of the hMSCs in coculture with slices of neonatal brain cortex. In this condition the hMSCs did not show any neuronal transdifferentiation but expressed neurotrophin low-affinity (NGFRp75) and high-affinity (trkC) receptors and released nerve growth factor (NGF) ...
... Abstract. Myogenic differentiation of galectin-1 pretreated human fetal mesenchymal stem cell... more ... Abstract. Myogenic differentiation of galectin-1 pretreated human fetal mesenchymal stem cells after intra-arterial injection into dystrophic mice / J. Chan, M. Gavina, M. Belicchi, Y. Torrente, JE Morgan, NM Fisk. - In: Atti del Congresso ...
Accumulation of unwanted/misfolded proteins in aggregates has been observed in airways of patient... more Accumulation of unwanted/misfolded proteins in aggregates has been observed in airways of patients with cystic fibrosis (CF), a life-threatening genetic disorder caused by mutations in the gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR). Here we show how the defective CFTR results in defective autophagy and decreases the clearance of aggresomes. Defective CFTR-induced upregulation of reactive oxygen species (ROS) and tissue transglutaminase (TG2) drive the crosslinking of beclin 1, leading to sequestration of phosphatidylinositol-3-kinase (PI(3)K) complex III and accumulation of p62, which regulates aggresome formation. Both CFTR knockdown and the overexpression of green fluorescent protein (GFP)-tagged-CFTR(F508del) induce beclin 1 downregulation and defective autophagy in non-CF airway epithelia through the ROS-TG2 pathway. Restoration of beclin 1 and autophagy by either beclin 1 overexpression, cystamine or antioxidants rescues the localization of the beclin 1 interactome to the endoplasmic reticulum and reverts the CF airway phenotype in vitro, in vivo in Scnn1b-transgenic and Cftr(F508del) homozygous mice, and in human CF nasal biopsies. Restoring beclin 1 or knocking down p62 rescued the trafficking of CFTR(F508del) to the cell surface. These data link the CFTR defect to autophagy deficiency, leading to the accumulation of protein aggregates and to lung inflammation.
Background information. Cell motility entails the reorganization of the cytoskeleton and membrane... more Background information. Cell motility entails the reorganization of the cytoskeleton and membrane trafficking for effective protrusion. The GIT-PIX protein complexes are involved in the regulation of cell motility and adhesion and in the endocytic traffic of members of the family of G-protein-coupled receptors. We have investigated the function of the endogenous GIT complexes in the regulation of cell motility stimulated by fMLP (formyl-Met-Leu-Phe) peptide, in a rat basophilic leukaemia RBL-2H3 cell line stably expressing an HA (haemagglutinin)-tagged receptor for the fMLP peptide. Results. Our analysis shows that RBL cells stably transfected with the chemoattractant receptor expressed both GIT1-PIX and GIT2-PIX endogenous complexes. We have used silencing of the different members of the complex by small interfering RNAs to study the effects on a number of events linked to agonist-induced cell migration. We found that cell adhesion was not affected by depletion of any of the proteins of the GIT complex, whereas agonist-enhanced cell spreading was inhibited. Analysis of agonist-stimulated haptotactic cell migration indicated a specific positive effect of GIT1 depletion on trans-well migration. The internalization of the formyl-peptide receptor was also inhibited by depletion of GIT1 and GIT2. The effects of the GIT complexes on trafficking of the receptors was confirmed by an antibody-enhanced agonist-induced internalization assay, showing that depletion of PIX, GIT1 or GIT2 protein caused decreased perinuclear accumulation of internalized receptors. Conclusions. Our results show that endogenous GIT complexes are involved in the regulation of chemoattractantinduced cell motility and receptor trafficking, and support previous findings indicating an important function of the GIT complexes in the regulation of different G-protein-coupled receptors. Our results also indicate that endogenous GIT1 and GIT2 regulate distinct subsets of agonist-induced responses and suggest a possible functional link between the control of receptor trafficking and the regulation of cell motility by GIT proteins.
Background: YKL-40 − a chitinase-like protein − was increased in patients with severe asthma and ... more Background: YKL-40 − a chitinase-like protein − was increased in patients with severe asthma and chronic obstructive pulmonary disease (COPD). Neutrophils secrete YKL-40. We hypothesized that increased YKL-40 levels in lung diseases reflect neutrophilic inflammation and that YKL-40 accumulates in the airways of cystic fibrosis patients (CF), a prototypic neutrophilic airway disease. We aimed to analyze YKL-40 levels in human and murine CF lung disease compared to COPD, asthma and control subjects. Methods: YKL-40 protein levels were measured in serum and sputum samples of CF, asthma, COPD and healthy individuals. Protein levels of the murine homologue BRP-39 were quantified in airway fluids from CF-like bENaC-Tg mice. Results: YKL-40 levels were significantly increased in human and murine CF airway fluids compared to asthma, COPD and healthy individuals. In both CF patients and bENaC-Tg mice, YKL-40/BRP-39 airway levels correlated with severity of obstructive lung disease. Conclusion: YKL-40 is increased in CF airway fluids and is negatively associated with pulmonary function. These findings suggest YKL-40 as potential biomarker and therapeutic target in CF lung disease.
Increasing evidence implicates both platelets and neutrophils in the formation, stabilization, an... more Increasing evidence implicates both platelets and neutrophils in the formation, stabilization, and growth of peripheral and coronary thrombi. Neutrophil extracellular traps (NETs) play a key role. The early events in the deregulated cross-talk between platelets and neutrophils are poorly characterized. To identify at the molecular level the mechanism through which platelets induce the generation of NETs in sterile conditions. The presence of NETs was determined in 26 thrombi from patients with acute myocardial infarction by immunohistochemistry and immunofluorescence and markers of NETs assessed in the plasma. In vitro NET generation was studied in static and in physiological flow conditions. Coronary thrombi mainly consist of activated platelets, neutrophils, and NETs in close proximity of platelets. Activated platelets commit neutrophils to NET generation. The event abates in the presence of competitive antagonists of the high mobility group box 1 (HMGB1) protein. Hmgb1(-/-) plate...
We have identified with molecular markers and purified by flow cytometry two populations of cells... more We have identified with molecular markers and purified by flow cytometry two populations of cells that are developmentally and anatomically related to blood vessel walls in human tissues: myoendothelial cells, found in skeletal muscle and coexpressing markers of endothelial and myogenic cells, and pericytes--aka mural cells--which surround endothelial cells in capillaries and microvessels. Purified myoendothelial cells and pericytes exhibit multilineage developmental potential and differentiate, in culture and in vivo, into skeletal myofibers, bone, cartilage, and adipocytes. Myoendothelial cells and pericytes can be cultured on the long term with sustained marker expression and differentiation potential and clonal populations thereof have been derived. Yet, these blood vessel wall-derived progenitors exhibit no tendency to malignant transformation upon extended culture. Our results suggest that multipotent progenitor cells, such as mesenchymal stem cells, previously isolated retrospectively from diverse cultured adult tissues are derived from a subset of perivascular cells. We present in this chapter the main strategies and tactics used to purify, culture on the long term, and phenotypically characterize these novel multipotent cells.
but only a cocktail including SCF, bFGF, EGF, VEGF, LIF, TEPA, IL6 showed a significant expansion... more but only a cocktail including SCF, bFGF, EGF, VEGF, LIF, TEPA, IL6 showed a significant expansion of stem cells in culture. In this condition we were able to expand the CD133+ cells for more than 50 passages over a 2-month period and we observed no indication of replicative senescence or significant changes in cellular division time during expansion period. Proliferating cells still had the capacity to form hematopoietic and endothelial colonies in semisolid media. Furthermore, we showed that expanded populations of CD133+ cells derived from blood maintain the capacity to differentiate into myogenic cells in vitro and in vivo. Human circulating CD133+ cells were also cultured at 5-or 20-percent oxygen in liquid culture in presence of the better cocktail of cytokines and we analysed and compared their expansion capacity and their vitality. The total number of cells increased 6-fold at 5-percent oxygen and could result in a better maintenance of the balance between primitive progenitor cell renewal and clonogenic progenitor expansion, thus representing a tool of remarkable therapeutic interest.
with also antioxidant properties, have beneficial effects in mdx mice. The drugs used are not ava... more with also antioxidant properties, have beneficial effects in mdx mice. The drugs used are not available for clinical studies. We tested whether genistein and flavocoxid, supplements with known antioxidant and antinflammatory properties readily available for clinical use, could have a beneficial effect on muscle function, morphology and biochemical pattern in mdx mice. Five-week old mdx mice received for five weeks either genistein (2 mg/kg i.p. daily), flavocoxid (5 mg/kg i.p. daily or vehicle; flavonoids treatment 1)'increased forelimb strength (p < 0.05) and strength normalized to weight (p < 0.05) and decreased fatigue (p < 0.05; 2) reduced serum creatine-kinase levels (p < 0.01; 3) increased GPX activity and reduced markers of oxidative stress (p < 0.05; 4) blunted NF-jB DNA-binding activity (p < 0.05; 5) reduces muscle necrosis (p < 0.01) and enhances regeneration (p < 0.05) with an augmented number of myogenin-positive satellite cells and myonuclei, and of developmental myosin heavy chainpositive fibers. Our results suggest that these flavonoids might have a beneficial effect on muscle function and morphology in mdx mice. Further studies are needed to investigate the biochemical substrates of such encouraging preliminary results taking into account that these supplements could be easily introduced in the daily diet of patients with DMD.
Background: Various prognostic serum and cellular markers have been identified for many diseases,... more Background: Various prognostic serum and cellular markers have been identified for many diseases, such as cardiovascular diseases and tumor pathologies. Here we assessed whether the levels of certain stem cells may predict the progression of Duchenne muscular dystrophy (DMD).
Perivascular multipotent mesenchymal progenitors exist in a variety of tissues, including the pla... more Perivascular multipotent mesenchymal progenitors exist in a variety of tissues, including the placenta. Here, we suggest that the abundant vasculature present in the human placenta can serve as a source of myogenic cells to regenerate skeletal muscle. Chorionic villi dissected from the mid-gestation human placenta were first transplanted intact into the gastrocnemius muscles of SCID=mdx mice, where they participated in muscle regeneration by producing myofibers expressing human dystrophin and spectrin. In vitro-cultured placental villi released rapidly adhering and migratory CD146+CD34ÀCD45ÀCD56À cells of putative perivascular origin that expressed mesenchymal stem cell markers. CD146+CD34ÀCD45ÀCD56À perivascular cells isolated and purified from the placental villi by flow cytometry were indeed highly myogenic in culture, and generated dystrophin-positive myofibers, and they promoted angiogenesis after transplantation into SCID=mdx mouse muscles. These observations confirm the existence of mesenchymal progenitor cells within the walls of human blood vessels, and suggest that the richly vascularized human placenta is an abundant source of perivascular myogenic cells able to migrate within dystrophic muscle and regenerate myofibers.
Uploads
Papers by Manuela Gavina