Contributions
Abstract: P385
Type: Poster
Abstract Category: Pathology and pathogenesis of MS - Pathology
Perivascular tissues of multiple human adult organs were recently found to harbor mesenchymal stem/stromal cells (MSCs) with phenotypical and functional characteristics similar to pericytes. MSCs display potent immunoregulatory and regenerative properties and are currently evaluated as cellular therapy for different disease"s, including Multiple Sclerosis, (MS). Although well defined in vitro, the true in vivo identity and function of MSCs is poorly investigated. In this study the presence, distribution and proliferative activity of a cell population termed “mesenchymal perivascular stromal cells” (MPCs) was identified and assessed in MS and healthy brain tissue. Serial sections of post-mortem brain tissue blocks from progressive MS (n=11) and healthy persons (n=5) were used for immunohistochemical analyses of MSC and pericyte markers. The MS tissue included active lesions (n=9), chronic active lesions (n=18), inactive lesions (n=5) and normal appearing white matter (n=7). Cells co-expressing MSC/perictye markers were exclusively found in the perivascular tissue of both healthy and MS brain tissue. Two distinct MPCs subtypes were identified by marker expression and localization, including a CD146+PDGFRbeta+ population in the tunica media and a CD73+CD271+PDGFRbeta+cell population in the adventitia. Active and chronic active demyelinating MS lesions possessed increased number of vessels with significantly increased localization of MPCs, most prominently found in the adventitial layer (p< 0.0001). Both MPC subpopulations displayed proliferative activity, as demonstrated with positive KI67 staining in both MS and healthy brain vessels. The CD146+PDGFRbeta+ population in chronic active lesions displayed increased proliferative activity compared to healthy tissues (p< 0.0001). Our data provide further evidence for the vascular niche as an origin for MSCs. In addition our results suggest that cerebral vessels contain mesenchymal progenitor cells that respond to disease processes in MS.
Disclosure: The authors have nothing to disclose.
Abstract: P385
Type: Poster
Abstract Category: Pathology and pathogenesis of MS - Pathology
Perivascular tissues of multiple human adult organs were recently found to harbor mesenchymal stem/stromal cells (MSCs) with phenotypical and functional characteristics similar to pericytes. MSCs display potent immunoregulatory and regenerative properties and are currently evaluated as cellular therapy for different disease"s, including Multiple Sclerosis, (MS). Although well defined in vitro, the true in vivo identity and function of MSCs is poorly investigated. In this study the presence, distribution and proliferative activity of a cell population termed “mesenchymal perivascular stromal cells” (MPCs) was identified and assessed in MS and healthy brain tissue. Serial sections of post-mortem brain tissue blocks from progressive MS (n=11) and healthy persons (n=5) were used for immunohistochemical analyses of MSC and pericyte markers. The MS tissue included active lesions (n=9), chronic active lesions (n=18), inactive lesions (n=5) and normal appearing white matter (n=7). Cells co-expressing MSC/perictye markers were exclusively found in the perivascular tissue of both healthy and MS brain tissue. Two distinct MPCs subtypes were identified by marker expression and localization, including a CD146+PDGFRbeta+ population in the tunica media and a CD73+CD271+PDGFRbeta+cell population in the adventitia. Active and chronic active demyelinating MS lesions possessed increased number of vessels with significantly increased localization of MPCs, most prominently found in the adventitial layer (p< 0.0001). Both MPC subpopulations displayed proliferative activity, as demonstrated with positive KI67 staining in both MS and healthy brain vessels. The CD146+PDGFRbeta+ population in chronic active lesions displayed increased proliferative activity compared to healthy tissues (p< 0.0001). Our data provide further evidence for the vascular niche as an origin for MSCs. In addition our results suggest that cerebral vessels contain mesenchymal progenitor cells that respond to disease processes in MS.
Disclosure: The authors have nothing to disclose.