The first patient to receive mismatched Mesenchymal Stem Cells was a twenty-year-old woman with acute myeloid leukemia treated with peripheral blood stem cells combined with MSC from her haploidentical father. Lazarus et al. reported on 46 patients who received HSCs and culture-expanded MSCs from HLA-identical siblings. Moderate to severe acute GvHD was observed in 28% of the patients, and chronic GvHD was seen in 61%. The two-year progression-free survival was observed in 53% of the patients. MSC infusion caused no acute or long-term MSC-associated adverse events.