We identify that miR-155 expression in both donor CD8<sup>+</sup> T cells and conventional CD4<sup>+</sup> CD25<sup>-</sup> T cells is pivotal for aGVHD pathogenesis.
Taken together, these data provide a mechanistic framework in which miR-155 delivered by EMPs is involved in aGVHD pathogenesis by activating specific T lymphocytes functions.
Correction: Endothelial microparticles delivering microRNA-155 into T lymphocytes are involved in the initiation of acute graft-versus-host disease following allogeneic hematopoietic stem cell transplantation.
Certain miRNAs such as miR-146a or miR-155 play an important role in the regulation of post-transplant immunity in mice.While some miRNAs e.g. miR-423 or miR-155 are regulated in plasma or full blood during acute GvHD also in man, the relevance and expression profile of miRNAs in T-cells after allogeneic SCT is unknown. miR-625-3p has recently been described to be overexpressed in colorectal malignancies where it promotes migration, invasion and apoptosis resistance.
The microRNA-155, a recently identified target for acute GVHD (aGVHD), was also found to be significantly induced in HLA mismatched MLC but not in the matched setting and its induction was not diminished by blocking IFNγ.