Impact of different mesenchymal stromal cell types on T-cell activation, proliferation and migration

Mesenchymal stromal cells (MSCs) isolated from different tissue sources may present distinct immunomodulatory profiles. As lymphocyte responses are a combination of several distinct steps, we evaluated and compared the impact of MSCs from different sources on the activation, proliferation and migration of T-cells. We demonstrated that tissue-derived MSCs have important immunomodulatory effects. AT-MSCs induced potent anti-proliferative and anti-inflammatory (IFN-gamma downregulation) effects and differentially modulated several T-cell activation markers (CD23, CD26, CD45, and CD69). Among all the MSC types tested, only AT-MSCs induced significant downregulation of CD26 and CD45 expression. Of importance, AT-MSCs maintained a sustained expression of CD69. AT-MSCs, particularly following exposure to an inflammatory environment, promoted the migration of lymphocytes into their surrounding environment. The AT-MSCs may increase recruitment of T lymphocytes by upregulation of IL-8 and CCL5 secretion. Following their migration, T-cells interact with MSCs, which can impair lymphocyte proliferation and activation depending on their origin. Inflammatory T-cells appeared to be progressively suppressed, which may lead to a population of lymphocytes with a regulatory phenotype. These findings are relevant, as they increase our understanding of the different immunomodulatory effect of MSCs as well as their behavior in an inflammatory environment. (c) 2013 Elsevier B.V. All rights reserved.