Down regulation of MHC-II expression in serial passages of allogenic bone marrow derived stromal cells for cell based therapy

Mesenchymal stem cells (MSC) show evidence of being potential candidates for allogenic application; however test methods to evaluate their suitability are not yet well established. The study evaluates the possible role of histocompatible markers for routine preclinical screening of MSCs for cell based therapies. The results in 5 healthy, prospective, allogenic donor-recipient pairs in co-culture experiments demonstrated downregulation of MHC-II expression up until passage 5. The lack of HLA-DR in cytotoxicity assays are suggestive of hypoimmunogenic nature of MSC's. The preproof-of concept in the current study throws new light in the potential wider clinical applicability of mesenchymal stem cells.