Paeoniflorin prevents acute graft-versus-host disease while preserving graft-versus-tumor effects
Acute graft-versus-host disease (aGVHD) remains a major complication after allogeneic hematopoietic stem cell transplantation (allo-HSCT). This study investigated the preventive effects of paeoniflorin (PF), a natural monoterpene glycoside, on aGVHD. Candidate herb-derived compounds against aGVHD were screened using SymMap, HERB, ADMETlab, and InflamNat, followed by molecular docking. The preventive effects of PF were evaluated in major histocompatibility complex (MHC)-mismatched murine aGVHD models. An entire-process paeoniflorin (EP-PF) regimen, involving donor pretreatment before transplantation and recipient treatment after transplantation, was proposed for enhancing the preventive effect. Survival, body weight, clinical score, hematopoietic reconstitution, donor T cell infiltration, cytokine and chemokine levels, gut injury, apoptosis, gut microbiota, transcriptomic changes, and graft-versus-tumor (GVT) activity were assessed. PF was identified as a promising multi-target compound for aGVHD prevention. PF reduced clinical severity, body weight loss, and mortality, while improving hematopoietic recovery and increasing hematopoietic stem/progenitor cell (HSPC) numbers. EP-PF regimen showed stronger protection than recipient-only PF administration. Mechanistically, EP-PF reduced intestinal donor cluster of differentiation 4 (CD4) positive and cluster of differentiation 8 (CD8) positive T cell infiltration, partially restored CD4 + /CD8 + T cell balance, and reversed inflammatory transcriptional programs in donor T cells. Moreover, EP-PF balanced serum levels of cytokines and chemokines, preserved gut barrier integrity, reduced intestinal apoptosis, and partially corrected gut microbiota dysbiosis. Importantly, EP-PF preserved donor cell-mediated tumor control in a green fluorescent protein (GFP)-labeled A20 GVT model. PF also directly inhibited the proliferation of hematologic tumor cells and promoted their apoptosis in vitro and in vivo . PF prevents experimental aGVHD through coordinated regulation of donor T cell responses, inflammatory mediators, hematopoietic reconstitution, intestinal barrier injury, apoptosis, and gut microbiota, while preserving GVT activity. These findings support PF as a potential prophylactic candidate for allo-HSCT.