Manuguerra-Gagné R. Boulos PR, Ammar A, Leblond FA, Krosl G, Pichette V, Lesk MR, Roy DC. Stem Cells. Transplantation of mesenchymal stem cells promotes tissue regeneration in a glaucoma model through laser-induced paracrine factor secretion and progenitor cell recruitment. 2013 Jun;31(6):1136-48
Impact scientifique: Le glaucome est une maladie dégénérative oculaire causant une perte de vision par hausse de la pression oculaire. L’origine de son développement est la perte de fonction du trabéculum, responsable de la sortie de l’humeur aqueuse. Pour les maladies dégénératives comme le glaucome, la recherche sur les cellules souches est un champ d’expertise extrêmement prometteur. Parmi elles, les cellules souches mésenchymales (MSC) sont capables de faciliter la guérison d’un tissu endommagé. Cet article démontre que les MSC sont capables d’activer des cellules progénitrices endogènes qui vont migrer dans le trabéculum et remplacer les cellules malades. Ces résultats permettent d’envisager des traitements cliniques pouvant considérablement améliorer la qualité de vie de ces patients
Contribution du Réseau: Le RRSV a octroyé une bourse d’étude à l’auteur principal de l’article, ce qui a permis la réalisation du projet.
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Résumé original
Among bone marrow cells, hematopoietic and mesenchymal components can contribute to repair damaged organs. Such cells are usually used in acute diseases but few options are available for the treatment of chronic disorders. In this study, we have used a laser-induced model of open angle glaucoma (OAG) to evaluate the potential of bone marrow cell populations and the mechanisms involved in tissue repair. In addition, we investigated laser-induced tissue remodeling as a method of targeting effector cells into damaged tissues. We demonstrate that among bone marrow cells, mesenchymal stem cells (MSC) induce trabecular meshwork regeneration. MSC injection into the ocular anterior chamber leads to far more efficient decrease in intraocular pressure (IOP) (p < .001) and healing than hematopoietic cells. This robust effect was attributable to paracrine factors from stressed MSC, as injection of conditioned medium from MSC exposed to low but not to normal oxygen levels resulted in an immediate decrease in IOP. Moreover, MSC and their secreted factors induced reactivation of a progenitor cell pool found in the ciliary body and increased cellular proliferation. Proliferating cells were observed within the chamber angle for at least 1 month. Laser-induced remodeling was able to target MSC to damaged areas with ensuing specific increases in ocular progenitor cells. Thus, our results identify MSC and their secretum as crucial mediators of tissue repair in OAG through reactivation of local neural progenitors. In addition, laser treatment could represent an appealing strategy to promote MSC-mediated progenitor cell recruitment and tissue repair in chronic diseases.
Cette image montre que les cellules mésenchymales (vert) induisent l’apparition de cellules progénitrices endogènes (rouge) dans un œil endommagé (droite et gauche en bas). Les cellules endogènes sont très peu présentes en l’absence des MSC (haut gauche).