engleski

The role of galectin-3 in immune cells activation

Galectin-3, a β-galactoside binding lectin exerts important roles in many (patho)physiological processes (adhesion, proliferation, differentiation, apoptosis, inflammation, neoplastic transformation, spreading metastases). Being one of the key lectins of innate and acquired immunity, galectin-3 is considered a powerful pro-inflammatory signal. It triggers/promotes respiratory burst in monocytes, acts as a monocyte/macrophage chemoattractant and promotes survival of inflammatory cells through its anti-apoptotic activity. The aim of this study was to ascertain the level of galectin-3 expression and explore it's role in (patho)physiological processes of monocytes and lymphocytes. Flow cytometry was used to determine the level of membrane and intracellular galectin-3 expression on a model THP-1 monocytic cell-line. We used lipopolysaccharide (LPS) activated and phorbol 12-myristate-13-acetate (PMA) differentiated, THP-1 cells cultured in RPMI 1640, supplemented with FCS and antibiotics. Galectin-3 was detected using anti-human galectin-3 primary, and labeled secondary antibodies. Dead cells were excluded by 7AAD. Macrophage-like morphology was confirmed by an elevated CD14 stain and surface adhesion. LPS-activated THP-1 cells have markedly up-regulated expression of intracellular galectin-3, while the surface level remains largely unchanged. Differentiation of monocytes to macrophages is associated with an increase of surface galectin-3 in respect to control cells. Using cytokine capture beads, we also studied the effects of recombinant galectin-3 on inflammatory cytokine secretion by human PBMC's from healthy volunteers. It was shown that exogenous galectin-3 influences cytokine secretion in human monocyte derived macrophages and lymphocytes. Given the importance of galectin-3 in monocyte and lymphocyte physiology, further experiments are necessary to elucidate it's roles in immune cells.

galectin-3; monocyte/macrophages; flow cytometry

DOI: 10.1111/j.1742-4658.2009.07049.x ; Rad je kao poster prezentiran i na skupovima: - EMBO Young Scientist Forum, održanom od 01.-17.06.2009., Zagreb, Hrvatska ; objavljen u Knjizi sazetaka, str. 39-39 ; http://www.bioinfo.hr/embo/index.php/abstracts.html ; - 10th Congress of the Croatian Society of Biochemistry and Molecular Biology (HDBMB 2010) The Secret Life of Biomolecules, odrzanom od 15.-18.09.2010., Opatija, Hrvatska ; objavljen u Knjizi sažetaka ; Zrinka Kovarik, Jadranka Varljen (ur.) ; Rijeka : Hrvatsko društvo za biokemiju i molekularnu biologiju, 2010. ; str. P61-P61.