Highlights
•Mesenchymal stromal cells influence the cells of the immune system.
This influence is mainly due to the release of paracrine factors.
Extracellular vesicles are emerging as new tool for cell-to-cell
communication.
Abstract
Mesenchymal stromal cells (MSCs) inhibit natural killer cell proliferation and
activity, suppress T lymphocyte proliferation, dendritic cells maturation and B
lymphocyte proliferation and activation. Moreover, MSCs may induce regulatory T
cells. Several factors released from MSCs have been implicated in their immune-
modulatory properties. These include soluble factors such as interleukins 6 and 10,
prostaglandin E2, hepatocyte growth factor, indoleamine 2,3-dioxygenase, nitric
oxide, transforming growth factor ß1, human leukocyte antigen and extracellular
vesicles. These vesicles released from cells have been characterized as a new
mechanism of cell-to-cell communication and emerged as mediators of the MSC-
immune-modulatory effects. In this review we focused our attention on the
extracellular vesicles as paracrine mediators of MC immune-modulation.