Glutathione (GSH), the most abundant nonprotein thiol functioning as an antioxidant, plays critical roles in maintaining
the core functions of mesenchymal stem cells (MSCs), which are used as a cellular immunotherapy for
graft-versus-host disease (GVHD). However, the role of GSH dynamics in MSCs remains elusive. Genome-wide
gene
expression profiling and high-throughput live-cell imaging assays revealed that CREB1 enforced the GSH-recovering
capacity (GRC) of MSCs through NRF2 by directly up-regulating NRF2 target genes responsible for GSH synthesis
and redox cycling. MSCs with enhanced GSH levels and GRC mediated by CREB1-NRF2 have improved
self-renewal, migratory, anti-inflammatory, and T cell suppression capacities. Administration of MSCs overexpressing
CREB1-NRF2 target genes alleviated GVHD in a humanized mouse model, resulting in improved survival,
decreased weight loss, and reduced histopathologic damages in GVHD target organs. Collectively, these findings
demonstrate the molecular and functional importance of the CREB1-NRF2 pathway in maintaining MSC GSH dynamics,
determining therapeutic outcomes for GVHD treatment.