Fucosylation enhances CD34⁺ hematopoietic stem cell homing and longevity via E-selectin-mediated adhesion and signaling.

BACKGROUND: Hematopoietic stem cell transplantation (HSCT) is a cornerstone treatment for blood disorders and hematological malignancies, although its efficacy is limited by inefficient stem cell homing to the bone marrow. We previously demonstrated that fucosylated HSC ligands interact with endothelial E-selectin to facilitate homing. However, the downstream consequences of modulating fucosylation in HSCs remain unclear. Here, we systematically characterized how enhancing or inhibiting fucosylation—via recombinant human fucosyltransferase 6 (FTVI) or 2-fluoro-L-fucose (2FF), respectively—affects migration, signaling, and engraftment of human granulocyte-colony stimulating factor-mobilized peripheral blood CD34⁺ (mPB-CD34⁺) cells. METHODS: Live-cell imaging under flow, phosphoproteomics, and transcriptomics were used to characterize rolling dynamics and intracellular signaling, and in vivo homing was assessed in immunodeficient xenograft mouse models. RESULTS: Fucosylation enhanced tether and sling formation, improved E-selectin binding, and increased homing to the bone marrow and spleen. FTVI-treated cells activated MAPK and PI3K/AKT/mTOR pathways and showed enriched Rho-GTPase signaling, associated with proliferation and migration. In contrast, 2FF-treated cells had impaired migration and reduced rolling efficiency. Long-term xenograft studies showed enhanced bone marrow engraftment/persistence of fucosylated cells without altering lineage output. CONCLUSION: Fucosylation critically modulates E-selectin interactions, migration, and intracellular signaling in HSCs. These findings highlight glycoengineering as a promising strategy to enhance HSC transplantation outcomes in cancer therapy.