Researchers conducted sequential Phase Ia and Ib clinical trials testing escalating doses of mesenchymal stromal cell (MSC) therapy in 24 patients with decompensated liver cirrhosis (DLC). Single doses ranging from 50 million to 200 million cells were tested in Phase Ia, followed by three-dose regimens in Phase Ib. No severe adverse events or dose-limiting toxicities occurred through 28-day follow-up. Multi-omics analyses — including single-cell RNA sequencing and mass cytometry — revealed dose-dependent immune modulation, particularly involving a novel monocyte subset called MX1+ monocytes. Higher doses and multiple-dose regimens showed preliminary improvements in liver function scores and quality of life, providing the first human evidence of a dose-response relationship for MSC immunomodulation in DLC.
