Galectin-1 and its novel ligand CD13 in liver tumor-derived sinusoidal endothelial cells

LUCIANA SARRIAS; MARISA MARIEL FERNÁNDEZ; FLORENCIA SARTI; MARÍA VICTORIA ESPELT; EMILIO LUIS MALCHIODI; GABRIEL ADRIÁN RABINOVICH; MARÍA TERESA ELOLA; MARÍA FERNANDA TRONCOSO

Mar del Plata

Congreso; Reunión Anual de Sociedades de Biociencias 2022; 2022

SAIC, SAI, SAFIS

Galectin-1 (Gal1), a β-galactoside-binding protein, is upregulated in hepatocellularcarcinoma. Previously we identified CD13 as a ligand for Gal1 in human SKHEP1 liver tumor-derived sinusoidal endothelial cells (LSEC) using a proteomic approach. CD13 is a glycosylatedmembrane exopeptidase upregulated in endothelial cells during tumor-related angiogenesis.Here we aimed to study direct, specific and glycan-dependent Gal1/CD13 interactionas well as the role of both proteins in SKHEP1 LSEC proliferation and migration.Gal1 interaction with CD13 was studied by Surface Plasmon Resonance (SPR) on aBiacore T100 system. CD13 was isolated from SKHEP1 LSEC membrane fraction using a Gal1-affinity column and coupled to a sensor chip CM5. Human recombinant Gal1 (0.075-20µM)was injected in each cycle. As a blank, a fraction of membrane proteins isolated from CD13knockout (CD13 KO, CRISPR-Cas9-based) SKHEP1 LSEC was immobilized on another chip. SPRassays confirmed Gal1 and CD13 interaction (Dissociation constant, K D : 3.1±0.2 x 10 -6 M).Preincubation with 1mM lactose, a well-established galectin inhibitor, abrogated thisinteraction while sucrose (1mM), a disaccharide not recognized by galectins, had no effect. Cellproliferation rate (t 72h vs. t 0 fold-change, MTT assay) in Gal1-silenced (shGal1) SKHEP1 LSECshowed a trend towards a decrease, while CD13 KO cells showed a significant lower rate of cellproliferation (3.43±0.27) versus control cells (scrambled (scr): 4.79±0.14, p