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See detailEccentric training improves tendon biomechanical properties: a rat model
Kaux, Jean-François ULg; Drion, Pierre ULg; Libertiaux, Vincent et al

in British Journal of Sports Medicine (2014, April), 48(7), 155

Background: Even if eccentric exercises appear favourable in primary prevention of tendons lesions and, especially, in secondary prevention after tendinopathy, the biomechanical changes to the tissue are ... [more ▼]

Background: Even if eccentric exercises appear favourable in primary prevention of tendons lesions and, especially, in secondary prevention after tendinopathy, the biomechanical changes to the tissue are not yet clear. Objective: We aimed to better define the biomechanical changes that affect healthy tendon after eccentric and concentric training. Design: Randomised controlled trial. Participants: Eighteen Sprague-Dawley rats of 2 months. Interventions: The six rats in the control group (U) were not subjected to physical exercise. The 12 remaining rats (6 in each group) ran on a treadmill set at a +15° incline for concentric training (C) or a -15° incline for eccentric training (E), at a speed of 17 m/min for 1 h, three times per week for 5 weeks. Main Outcome Measurements: The tricipital, patellar and Achilles tendons were subsequently removed to perform a traction test until rupture, and a histological analysis was performed. Results: There was a significant improvement in the rupture force of the patellar and tricipital tendons between the U and E groups. The tricipital tendons in the control group presented a significantly smaller cross-section than the E- and C-trained groups, but none between E and C groups. No significant difference was observed for the mechanical stress at rupture per surface unit between the three groups for all three tendons. However, a tendency towards improvement these values was observed between the trained and the U groups for the patellar tendon. Histological studies demonstrated the tendency of the development of a greater number of blood vessels and a larger quantity of collagen in the eccentric group. Conclusions: The mechanical properties of tendons in rats improve after specific training, especially following eccentric training. Our results partly explained how mechanical loading, especially in eccentric mode, could improve the tendon structure. [less ▲]

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See detailSpinal Cord Injuries – How Could Adult Mesenchymal and Neural Crest Stem Cells Take Up the Challenge?
Neirinckx, Virginie ULg; CANTINIEAUX, Dorothée ULg; Coste, Cécile ULg et al

in Stem Cells (2013)

Since several years, adult/perinatal mesenchymal and neural crest stem cells have been widely used to help experimental animal to recover from spinal cord injury. More interestingly, recent clinical ... [more ▼]

Since several years, adult/perinatal mesenchymal and neural crest stem cells have been widely used to help experimental animal to recover from spinal cord injury. More interestingly, recent clinical trials confirmed the beneficial effect of those stem cells, which improve functional score of patients suffering from such lesions. However, a complete understanding of the mechanisms of stem cell-induced recovery is seriously lacking. Indeed, spinal cord injuries gathered a wide range of biochemical and physiopathological events (such as inflammation, oxidative stress, axonal damage, demyelination, etc) and the genuine healing process after cell transplantation is not sufficiently defined. This review aims to sum up recent data about cell therapy in spinal cord lesions using mesenchymal or recently identified neural crest stem cells, by describing precisely which physiopathological parameter is affected and the exact processes underlying the observed changes. Overall, although significant advances are acknowledged, it seems that further deep mechanistic investigation is needed for the development of optimized and efficient cell-based therapy protocols. [less ▲]

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See detailEccentric training improves tendon biomechanical properties: a rat model
Kaux, Jean-François ULg; Drion, Pierre ULg; Libertiaux, Vincent et al

in Journal of Orthopaedic Research (2013), 31(1), 119-124

Introduction: The treatment of choice for tendinopathies is eccentric reeducation. Although the clinical results appear favourable, the biomechanical changes to the tissue are not yet clear. Even if the ... [more ▼]

Introduction: The treatment of choice for tendinopathies is eccentric reeducation. Although the clinical results appear favourable, the biomechanical changes to the tissue are not yet clear. Even if the mechanotransduction theory is commonly accepted, the physiology of tendons is not clearly understood. We aimed to better define the biomechanical and histological changes that affect healthy tendon after eccentric and concentric training. Materiel and Methods: This study compared the effects of 2 methods of training (eccentric (E) training and concentric (C) training) with untrained (U) rats. The animals were trained over a period of 5 weeks. The tricipital, patellar and Achilles tendons were removed, measured and a tensile test until failure was performed. A histological analysis (hematoxylin and eosin and Masson's trichrome stains) was also realized. Results: There was a significant increase in the rupture force of the patellar and tricipital tendons between the U and E groups. The tricipital tendons in the control group presented a significantly smaller cross-sectional area than the E- and C-trained groups, but none was constated between E and C groups. No significant difference was observed for the mechanical stress between the three groups for all three tendons. Histological studies demonstrated the development of a greater number of blood vessels and a larger quantity of collagen in the E group. Discussion and conclusion: The mechanical properties of tendons in rats improve after specific training, especially following eccentric training. Our results partly explained how mechanical loading, especially in eccentric mode, could improve the healing of tendon. [less ▲]

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See detailConditioned Medium from Bone marrow-derived Mesenchymal Stem Cells improves recovery after Spinal Cord Injury in rats: an original strategy to avoid cell transplantation.
CANTINIEAUX, Dorothée ULg; QUERTAINMONT, Renaud; BLACHER, Silvia ULg et al

in PLoS ONE (2013), 8(8), 69515

Spinal cord injury triggers irreversible loss of motor and sensory functions. Numerous strategies aiming at repairing the injured spinal cord have been studied. Among them, the use of bone marrow-derived ... [more ▼]

Spinal cord injury triggers irreversible loss of motor and sensory functions. Numerous strategies aiming at repairing the injured spinal cord have been studied. Among them, the use of bone marrow-derived mesenchymal stem cells (BMSCs) is promising. Indeed, these cells possess interesting properties to modulate CNS environment and allow axon regeneration and functional recovery. Unfortunately, BMSC survival and differentiation within the host spinal cord remain poor, and these cells have been found to have various adverse effects when grafted in other pathological contexts. Moreover, paracrine-mediated actions have been proposed to explain the beneficial effects of BMSC transplantation after spinal cord injury. We thus decided to deliver BMSC-released factors to spinal cord injured rats and to study, in parallel, their properties in vitro. We show that, in vitro, BMSC-conditioned medium (BMSC-CM) protects neurons from apoptosis, activates macrophages and is pro-angiogenic. In vivo, BMSC-CM administered after spinal cord contusion improves motor recovery. Histological analysis confirms the pro-angiogenic action of BMSC-CM, as well as a tissue protection effect. Finally, the characterization of BMSC-CM by cytokine array and ELISA identified trophic factors as well as cytokines likely involved in the beneficial observed effects. In conclusion, our results support the paracrine-mediated mode of action of BMSCs and raise the possibility to develop a cell-free therapeutic approach. [less ▲]

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See detailInfluence of type of contraction upon tendinous tissue during training: animal model
Kaux, Jean-François ULg; Drion, Pierre ULg; Croisier, Jean-Louis ULg et al

in Meeusen, R; Duchateau, J; Roelands, B (Eds.) et al Book of Abstracts of the 17th annual Congress of the ECSS (2012, July)

Introduction: The treatment of choice for tendinopathies is eccentric reeducation. Although the clinical results appear favourable, the biomechanical changes to the tissue are not yet clear. Materiel and ... [more ▼]

Introduction: The treatment of choice for tendinopathies is eccentric reeducation. Although the clinical results appear favourable, the biomechanical changes to the tissue are not yet clear. Materiel and methods: This study compared the effects of two methods of training (eccentric (E) training and concentric (C) training) with untrained (U) rats. The animals underwent training over a period of five weeks. The tricipital, patellar and Achilles tendons were subsequently removed to perform a traction test to the point of tendon rupture, and a histological analysis was performed. Results: There was a significant improvement in the rupture force of the patellar and tricipital tendons between the U and E groups. The tricipital tendons in the control group presented a significantly smaller cross-section than the E- and C-trained groups. No significant difference was observed for the constraints between the three groups for all three tendons. However, a tendency towards improvement was observed between the trained and the U groups for the patellar tendon. Histological studies demonstrated the development of a greater number of blood vessels and a larger quantity of collagen in the eccentric group. Discussion and conclusion: The mechanical properties of tendons in rats improve after specific training, especially following eccentric training. [less ▲]

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See detailMesenchymal Stem Cell Graft Improves Recovery after Spinal Cord Injury in Adult Rats through Neurotrophic and Pro-Angiogenic Actions.
Quertainmont, Renaud; Cantinieaux, Dorothée ULg; Botman, Olivier et al

in PLoS ONE (2012), 7(6), 39500

Numerous strategies have been managed to improve functional recovery after spinal cord injury (SCI) but an optimal strategy doesn't exist yet. Actually, it is the complexity of the injured spinal cord ... [more ▼]

Numerous strategies have been managed to improve functional recovery after spinal cord injury (SCI) but an optimal strategy doesn't exist yet. Actually, it is the complexity of the injured spinal cord pathophysiology that begets the multifactorial approaches assessed to favour tissue protection, axonal regrowth and functional recovery. In this context, it appears that mesenchymal stem cells (MSCs) could take an interesting part. The aim of this study is to graft MSCs after a spinal cord compression injury in adult rat to assess their effect on functional recovery and to highlight their mechanisms of action. We found that in intravenously grafted animals, MSCs induce, as early as 1 week after the graft, an improvement of their open field and grid navigation scores compared to control animals. At the histological analysis of their dissected spinal cord, no MSCs were found within the host despite their BrdU labelling performed before the graft, whatever the delay observed: 7, 14 or 21 days. However, a cytokine array performed on spinal cord extracts 3 days after MSC graft reveals a significant increase of NGF expression in the injured tissue. Also, a significant tissue sparing effect of MSC graft was observed. Finally, we also show that MSCs promote vascularisation, as the density of blood vessels within the lesioned area was higher in grafted rats. In conclusion, we bring here some new evidences that MSCs most likely act throughout their secretions and not via their own integration/differentiation within the host tissue. [less ▲]

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See detailInfluence sur le tissu tendino(-musculaire) du mode de contraction en entraînement : modèle animal
Kaux, Jean-François ULg; Drion, Pierre ULg; Croisier, Jean-Louis ULg et al

in Julia, Marc; Hirt, Daniel; Croisier, Jean-Louis (Eds.) et al Tendon et jonction tendino-musculaire - De la biomécanique aux applications thérapeutiques (2011)

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See detailInvolvement of placental growth factor in Wallerian degeneration
Chaballe, Linda ULg; Close, Pierre ULg; SEMPELS, Maxime ULg et al

in Glia (2011), 59(3), 379-396

Wallerian degeneration (WD) is an inflammatory process of nerve degeneration, which occurs more rapidly in the peripheral nervous system compared with the central nervous system, resulting, respectively ... [more ▼]

Wallerian degeneration (WD) is an inflammatory process of nerve degeneration, which occurs more rapidly in the peripheral nervous system compared with the central nervous system, resulting, respectively in successful and aborted axon regeneration. In the peripheral nervous system, Schwann cells (SCs) and macrophages, under the control of a network of cytokines and chemokines, represent the main cell types involved in this process. Within this network, the role of placental growth factor (PlGF) remains totally unknown. However, properties like monocyte activation/attraction, ability to increase expression of pro-inflammatory molecules, as well as neuroprotective effects, make it a candidate likely implicated in this process. Also, nothing is described about the expression and localization of this molecule in the peripheral nervous system. To address these original questions, we decided to study PlGF expression under physiological and degenerative conditions and to explore its role in WD, using a model of sciatic nerve transection in wild-type and Pgf(-/-) mice. Our data show dynamic changes of PlGF expression, from periaxonal in normal nerve to SCs 24h postinjury, in parallel with a p65/NF-κB recruitment on Pgf promoter. After injury, SC proliferation is reduced by 30% in absence of PlGF. Macrophage invasion is significantly delayed in Pgf(-/-) mice compared with wild-type mice, which results in worse functional recovery. MCP-1 and proMMP-9 exhibit a 3-fold reduction of their relative expressions in Pgf(-/-) injured nerves, as demonstrated by cytokine array. In conclusion, this work originally describes PlGF as a novel member of the cytokine network of WD. [less ▲]

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See detailPost-mortem assessment of rat spinal cord injury and white matter sparing using inversion recovery-supported proton density magnetic resonance imaging
Scholtes, Félix ULg; Theunissen, E.; Phan Ba, Remy ULg et al

in Spinal Cord : The Official Journal of the International Medical Society of Paraplegia (2011)

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See detailPlacental growth factor: a tissue modelling factor with therapeutic potentials in neurology?
Chaballe, Linda ULg; Schoenen, Jean ULg; Franzen, Rachelle ULg

in Acta Neurologica Belgica (2011), 111(1), 10-7

Placental growth factor (PlGF) is an angiogenic factor that belongs to the vascular endothelial growth factor (VEGF) family. Besides its well known capacity to potentiate the angiogenic action of VEGF ... [more ▼]

Placental growth factor (PlGF) is an angiogenic factor that belongs to the vascular endothelial growth factor (VEGF) family. Besides its well known capacity to potentiate the angiogenic action of VEGF, PlGF also participates in inflammatory processes by attracting and activating monocytes; it plays therefore more specifically a role in pathological conditions. PIGF and its two receptors, VEGFR-1 and neuropilins (NRPs), are expressed in the brain and increase after experimental stroke, but their precise functions in the nervous system remain underexplored. In this review article, we summarize present knowledge on the role of PlGF in various nervous system disease processes. Given the available data, P1GF has neuroprotective and neurotrophic properties that make it an actor of considerable interest in the pathophysiology and potentially in the therapy of degenerative and traumatic brain or spinal cord diseases. [less ▲]

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See detailThe spinal cord ependymal region: A stem cell niche in the caudal central nervous system
Hugnot, Jean-Philippe; Franzen, Rachelle ULg

in Frontiers in Bioscience : A Journal and Virtual Library (2011), (16), 1044-1059

In the brain, specific signalling pathways localized in highly organized regions called niches, allow the persistence of a pool of stem and progenitor cells that generate new neurons and glial cells in ... [more ▼]

In the brain, specific signalling pathways localized in highly organized regions called niches, allow the persistence of a pool of stem and progenitor cells that generate new neurons and glial cells in adulthood. Much less is known on the spinal cord central canal niche where a sustained adult neurogenesis is not observed. Here we review our current knowledge of this caudal niche in normal and pathological situations. Far from being a simple layer of homogenous cells, this region is composed of several cell types localized at specific locations, expressing characteristic markers and with different morphologies and functions. We further report on a screen of online geneexpression databases to better define this spinal cord niche. Several genes were found to be preferentially expressed within or around the central canal region (Bmp6, CXCR4, Gdf10, Fzd3, Mdk, Nrtn, Rbp1, Shh, Sox4, Wnt7a) some of which by specific cellular subtypes. In depth characterization of the spinal cord niche constitutes a framework to make the most out of this endogenous cell pool in spinal cord disorders. [less ▲]

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See detailIntrinsic modification of tendon structure after concentric or excentric training
Kaux, Jean-François ULg; Drion, Pierre ULg; Besançon, Benoît et al

Poster (2010, November 25)

Introduction: It is well known that eccentric training is a successful way of treating chronic tendinopathy. Although clinical results are very positive, beneficial morphological and histological effects ... [more ▼]

Introduction: It is well known that eccentric training is a successful way of treating chronic tendinopathy. Although clinical results are very positive, beneficial morphological and histological effects have not yet been elucidated. The aim of our experiment was to determine if there exist any intrinsic modifications in a tendon trained in concentric or eccentric modes, in a rat model, using an original method of measurement (cryo-jaws). Methods: 18 rats were divided into 3 groups: 6 for the control group, without physical restraint; 12 for a training of1 hour, 3 times a week, for 5 weeks, at a speed of 17m/min (1km/h), on a inclined treadmill: 6 rats running uphill at +15° for the concentric effort (group C) and 6 rats running downhill at -15° for the eccentric effort (group E). After this training period, the Achilles, patellar and tricipital tendons of both limbs were surgically removed in all 18 rats. Tendons taken from five rats of each group were subjected to a tensile test up to rupture using a “cryo” jaw. Tendons of the remaining rat of each group were subjected to a histological study. Results: The results showed significant changes in group E only: (1) an increase of the force required to rupture the patellar and tricipital tendons; (2) an improvement of the ratio between the force necessary to rupture the tricipital tendon and the body mass of the rats; (3) an increase of the surface area of the section of the tricipital tendon. No significant change was observed as far as constraint was concerned between groups. Histologically, we saw, in the group E, more peripheral blood vessels and a greater proportion of collagen. Conclusion: This study showed that the mechanical properties of tendon tissue are enhanced by eccentric training. Tendons become stronger, the amount of collagen increases and there is probably more interaction between collagen fibers (mechanotransduction). [less ▲]

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See detailInfluence du mode de contraction sur le tendon : modèle animal
Kaux, Jean-François ULg; Drion, Pierre ULg; Besançon, Benoît et al

in 3ème Congrès Commun SFMS - SFTS (2010, October 01)

Introduction : Les tendinopathies sont fréquentes et touchent aussi bien les membres supérieurs que les membres inférieurs. La rééducation excentrique constitue une thérapeutique de choix dans le ... [more ▼]

Introduction : Les tendinopathies sont fréquentes et touchent aussi bien les membres supérieurs que les membres inférieurs. La rééducation excentrique constitue une thérapeutique de choix dans le traitement des tendinopathies. Malgré les résultats favorables en clinique, les effets morphologiques et biochimiques n’ont pas encore été élucidés. Matériel et méthodes : Dix-huit rats de souche Sprague-Dawley adultes ont été répartis en trois groupes : 6 témoins (groupe T) qui ne sont soumis à aucune contrainte physique ; 6 soumis à un effort concentrique (groupe C), course en montée ; 6 soumis à un effort excentrique (groupe E), course en descente. Les 12 rats des groupes C et E ont dû courir sur un tapis roulant incliné à +15° (groupe C) ou -15° (groupe E) à une vitesse de 17m/min (1km/h) pendant une heure à raison de trois séances par semaine pendant 5 semaines. Au terme de l’entraînement, les tendons achilléens, rotuliens et tricipitaux ont été prélevés bilatéralement. Les tendons de cinq rats de chaque groupe ont bénéficié d’une évaluation biomécanique (test de traction à l’aide de mors type « cryo-jaws »). Les tendons du sixième rat de chaque groupe ont permis l’étude histologique (coloration à l’hématoxyline-éosine et trichrome de Masson). Résultats : Le groupe E présente une augmentation de la tension de rupture des tendons rotuliens (29 ,5% ; p=0,047) et tricipitaux (72% ; p=0,018), une amélioration du rapport Force/Masse pour le tendon tricipital (54% ; p=0,043) ainsi qu’une augmentation de la section tendineuse tricipitale (74% ; p=0,008). Aucune variation pour aucun des tendons entre les groupes n’est relevée pour le paramètre contrainte (=Force/Section). Histologiquement, les tendons du groupe E se caractérisent par une plus grande quantité de vaisseaux sanguins périphériques ainsi qu’une plus grande proportion de collagène. Conclusion : Cette étude démontre que les propriétés mécaniques du tendon sont améliorées après un entraînement excentrique. Le tendon plus résistant augmente sa quantité de collagène et probablement les interactions entre les fibres de collagène. [less ▲]

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See detailInfluence of the contraction mode on the tendon structure - Rat model
Kaux, Jean-François ULg; Drion, Pierre ULg; Besançon, Benoît et al

in 2nd Congress of European College of Sport & Exercise Physicians - Conference Brochure 2010: Abstracts and CVs (2010, September 09)

Introduction: Tendinopathies are common in sport and affect both upper and lower limbs. Eccentric rehabilitation is a successful way of treating them and now is becoming the “gold treatment”. Although ... [more ▼]

Introduction: Tendinopathies are common in sport and affect both upper and lower limbs. Eccentric rehabilitation is a successful way of treating them and now is becoming the “gold treatment”. Although clinical results are very favorable, beneficial morphological and histological effects have not yet been elucidated. The aim of our experiment was to determine if there exist any intrinsic modifications in a tendon trained in concentric or eccentric modes, in a rat model. Methods: 18 rats were divided into 3 groups: 6 for the control group, without physical restraint; 12 for a training of1 hour, 3 times a week, for 5 weeks, at a speed of 17m/min (1km/h), on a inclined treadmill: 6 rats running uphill at +15° for the concentric effort (group C) and 6 rats running downhill at -15° for the eccentric effort (group E). After this training period, the Achilles, patellar and tricipital tendons of both limbs were surgically removed in all 18 rats. Tendons taken from five rats of each group were subjected to a tensile test up to rupture using a “cryo” jaw. Tendons of the remaining rat of each group were subjected to a histological study. Results: The results showed significant changes in group E only: (1) an increase of the force required to rupture the patellar and tricipital tendons; (2) an improvement of the ratio between the force necessary to rupture the tricipital tendon and the body mass of the rats; (3) an increase of the surface area of the section of the tricipital tendon. No significant change was observed as far as constraint was concerned between groups. Histologically, we saw, in the group E, more peripheral blood vessels and a greater proportion of collagen. Conclusion: This study showed that the mechanical properties of tendon tissue are enhanced by eccentric training. Tendons become stronger, the amount of collagen increases and there is probably more interaction between collagen fibers (mechanotransduction). [less ▲]

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See detailInvolvement of Placental growth factor in Wallerian degeneration
Chaballe, Linda ULg; Close, Pierre ULg; Sempels, Maxime ULg et al

Poster (2010, September)

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See detailSTEM CELLS IN THE ADULT RAT SPINAL CORD: PLASTICITY AFTER INJURY AND TREADMILL TRAINING EXERCISE.
Foret, Ariane ULg; Quertainmont, Renaud ULg; Botman, O. et al

in Journal of Neurochemistry (2010), 112(3), 762-772

ABSTRACT Ependymal cells located around the central canal of the adult spinal cord are considered as a source of neural stem cells (NSCs) and represent an interesting pool of endogenous stem cells for ... [more ▼]

ABSTRACT Ependymal cells located around the central canal of the adult spinal cord are considered as a source of neural stem cells (NSCs) and represent an interesting pool of endogenous stem cells for repair strategies. Physical exercise is known to increase ependymal cell proliferation, while improving functional recovery. In this work, we further characterized those endogenous NSCs within the normal and injured adult rat spinal cord and investigated the effects of treadmill training using immunohistochemical and behavioural studies. In uninjured untrained rats, Sox-2, a NSC marker, was detected in all ependymal cells of the central canal, and also scattered throughout the parenchyma of the spinal cord. Within the lesion, Sox-2 expression increased transiently, while the number of nestin-positive ependymal cells increased with a concomitant enhancement of proliferation, as indicated by the mitotic markers Ki67 and BrdU. Exercise, which improved functional recovery and autonomous micturition, maintained nestin expression in both injured and uninjured spinal cords, with a positive correlation between locomotor recovery and the number of nestin-positive cells. [less ▲]

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See detailNeural differentiation potential of human bone marrow-derived mesenchymal stromal cells: misleading marker gene expression
MONTZKA, Katrin; Lassonczyk, Nina; Tschöke, Beate et al

in BMC Neuroscience (2009), 10

Background: In contrast to pluripotent embryonic stem cells, adult stem cells have been considered to be multipotent, being somewhat more restricted in their differentiation capacity and only giving rise ... [more ▼]

Background: In contrast to pluripotent embryonic stem cells, adult stem cells have been considered to be multipotent, being somewhat more restricted in their differentiation capacity and only giving rise to cell types related to their tissue of origin. Several studies, however, have reported that bone marrow-derived mesenchymal stromal cells (MSCs) are capable of transdifferentiating to neural cell types, effectively crossing normal lineage restriction boundaries. Such reports have been based on the detection of neural-related proteins by the differentiated MSCs. In order to assess the potential of human adult MSCs to undergo true differentiation to a neural lineage and to determine the degree of homogeneity between donor samples, we have used RT-PCR and immunocytochemistry to investigate the basal expression of a range of neural related mRNAs and proteins in populations of non-differentiated MSCs obtained from 4 donors. Results: The expression analysis revealed that several of the commonly used marker genes from other studies like nestin, Enolase2 and microtubule associated protein 1b (MAP1b) are already expressed by undifferentiated human MSCs. Furthermore, mRNA for some of the neural-related transcription factors, e.g. Engrailed-1 and Nurr1 were also strongly expressed. However, several other neural-related mRNAs (e.g. DRD2, enolase2, NFL and MBP) could be identified, but not in all donor samples. Similarly, synaptic vesicle-related mRNA, STX1A could only be detected in 2 of the 4 undifferentiated donor hMSC samples. More significantly, each donor sample revealed a unique expression pattern, demonstrating a significant variation of marker expression. Conclusion: The present study highlights the existence of an inter-donor variability of expression of neuralrelated markers in human MSC samples that has not previously been described. This donor-related heterogeneity might influence the reproducibility of transdifferentiation protocols as well as contributing to the ongoing controversy about differentiation capacities of MSCs. Therefore, further studies need to consider the differences between donor samples prior to any treatment as well as the possibility of harvesting donor cells that may be inappropriate for transplantation strategies. [less ▲]

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