Exploring the role of the oral microbiome in cGVHD. In a clinical allo-HCT cohort, the cumulative incidence of cGVHD was associated with profound OM. In a mouse model, OLP was used to induce oral inflammation and dysbiosis. Findings from these experiments revealed oral pathobionts in the local LNs and the intestine, as well as the activation of antigen-presenting cells (APCs) and proliferation of donor T cells, likely contributing to cGVHD exacerbation. Figure created with BioRender.com.