The Regulation of Microglia Activity and the Production of IL-1α and IL-6 in the Degenerated Retina by Mesenchymal Stem Cells

Activation of immune response and production of proinflammatory factors plays an important role in the development and progression of retinal degenerative diseases (RDD). For this reason, focusing on immunomodulation is potential option for the efficient ophthalmological therapy. Mesenchymal stem cells (MSCs) have been study in the treatment of RDD mainly due to their regenerative and neuroprotective actions. Nevertheless, MSCs also possess several immunomodulatory properties. Our study shows that NaIO3-induced degeneration increased in vitro and in vivo expression of genes for Interleukin (IL)-1α and IL-6 in the mouse retinal tissue. In addition, intraperitoneal application of NaIO3 increased expression of gene for Iba-1 and infiltration of CD45+CD11b+ cells into the retina. CD45+ population was also responsible for the production of IL-1α while IL-6 was produced by CD45- cells. Cocultivation of degenerated retina in the presence of MSCs decreased the expression and production of both studied cytokines and expression of gene for Iba-1 in the retinal tissue. On contrary, it was observed that MSCs treated with supernatant from degenerated retina increased the expression of genes for cyclooxygenase-2, transforming growth factor-β, programmed-death ligand 1 and nerve growth factor. These results show that MSCs are able to regulate immune reaction in the degenerated retinal environment.