Pretransplant chemotherapy and irradiation release damage-associated molecular patterns (DAMPs) that bind to pattern-recognition receptors and activate dendritic cells to present antigen to donor T cells, thereby worsening graft-versus-host disease (GVHD). Binding of CD24Fc with sialic acid–binding immunoglobulin-type lectin 10 (Siglec-10) inhibits pattern-recognition receptor signaling and the downstream effects of DAMPs on dendritic cell activation, T-cell activation, and GVHD. Figure adapted from the visual abstract of the article by Magenau et al.¹