Historically, research on chylomicron entry into intestinal lymphatic vessels (lacteals) has been polarized between paracellular and transcellular transport models. In this issue of the JCI, Sun et al. identified GPR182 as a lipoprotein receptor in lymphatic endothelial cells (LECs), profoundly advancing our understanding of intestinal lipid absorption. They observed poor fat absorption in GPR182-deficient mice and demonstrated the role of GPR182 in transporting chylomicrons across the LECs into the lacteal lumen. This discovery establishes a molecular basis for transcellular transport of chylomicrons, challenging the traditional view that lacteal lipid entry is predominantly paracellular. By linking receptor-mediated uptake to impaired fat absorption and protection against fat-induced obesity and steatosis, this study expands the biological and translational implications of lacteal transport. Consequently, rather than favoring a single model, future research should investigate the integration of both paracellular and transcellular transport models in vivo.
Liqing Yu