Human Bone Marrow Mesenchymal Stem/Stromal Cells Exposed to an Inflammatory Environment Increase the Expression of ICAM‐1 and Release Microvesicles Enriched in This Adhesive Molecule: Analysis of the Participation of TNF‐ <i>α</i> and IFN‐ <i>γ</i>
Juan José Montesinos, Lucero López-García, Víctor Adrián Cortés-Morales, Lourdes Arriaga‐Pizano, Ricardo Valle‐Rios, Guadalupe R. Fajardo-Orduña, Marta Elena Castro-Manrreza
Abstract
Bone marrow mesenchymal stem/stromal cells (BM‐MSCs) have immunoregulatory capacity; therefore, they have been used in different clinical protocols in which it is necessary to decrease the immune response. This capacity is mainly regulated by TNF‐ α and IFN‐ γ , and it has been observed that cell‐cell contact, mainly mediated by ICAM‐1, is important for MSCs to carry out efficient immunoregulation. Therefore, in the present work, we analyzed the effect of TNF‐ α alone or in combination with IFN‐ γ on the expression of ICAM‐1. Besides, given the importance of cell contact in the immunoregulatory function of MSCs, we analyzed whether these cells release ICAM‐1 + microvesicles (MVs). Our results show for the first time that TNF‐ α is capable of increasing the early expression of ICAM‐1 in human BM‐MSCs. Also, we observed that TNF‐ α and IFN‐ γ have a synergistic effect on the increase in the expression of ICAM‐1. Furthermore, we found that BM‐MSCs exposed to an inflammatory environment release MVs enriched in ICAM‐1 (MVs‐ICAM‐1 high ). The knowledge generated in this study will contribute to the improvement of in vitro conditioning protocols that favor the therapeutic effect of these cells or their products.