Fucosylation pathway and selectin ligands (Fuc-SL)

The fucosylation pathway and selectin ligands represent a critical biochemical axis responsible for mediating cell-cell interactions, particularly between leukocytes and the vascular endothelium. This pathway involves the enzymatic addition of fucose moieties by fucosyltransferases to glycan precursors, creating functional ligands such as Sialyl-Lewis X (sLeX). These ligands are recognized by the selectin family of adhesion molecules (E-, P-, and L-selectin), which facilitate the initial 'rolling' phase of leukocyte recruitment during inflammation and hematopoiesis. In pathological states, this pathway is frequently hijacked; for instance, cancer cells overexpress fucosylated ligands to facilitate metastasis and evade immune detection, while in sickle cell disease, overactive selectin-mediated adhesion contributes to vaso-occlusive crises. Therapeutic strategies include small molecule mimetics that block ligand-receptor binding and inhibitors of the fucosylation machinery to reduce the density of pro-inflammatory and pro-metastatic glycans on the cell surface.

Other names

Sialyl-Lewis X (sLeX) biosynthesisSelectin ligand pathwayFucosyltransferase pathwayGDP-fucose metabolic pathwayLeukocyte-endothelial adhesion pathway

Drugs targeting this pathway typically act as competitive inhibitors of selectin binding (mimicking sLeX), inhibitors of fucosyltransferase enzymes (FUTs) to prevent ligand synthesis, or monoclonal antibodies that block the selectin receptors themselves to prevent leukocyte adhesion and rolling.