title: Galectin-1-matured human monocyte-derived dendritic cells have enhanced migration through extracellular matrix.
abstract: Dendritic cells (DCs) are potent mediators of the immune response, and can be activated by exogenous pathogen components. Galectin-1 is a member of the conserved beta-galactoside-binding lectin family that binds galactoside residues on cell surface glycoconjugates. Galectin-1 is known to play a role in immune regulation via action on multiple immune cells. However, its effects on human DCs are unknown. In this study, we show that galectin-1 induces a phenotypic and functional maturation in human monocyte-derived DCs (MDDCs) similar to but distinct from the activity of the exogenous pathogen stimuli, LPS. Immature human MDDCs exposed to galectin-1 up-regulated cell surface markers characteristic of DC maturation (CD40, CD83, CD86, and HLA-DR), secreted high levels of IL-6 and TNF-alpha, stimulated T cell proliferation, and showed reduced endocytic capacity, similar to LPS-matured MDDCs. However, unlike LPS-matured DCs, galectin-1-treated MDDCs did not produce the Th1-polarizing cytokine IL-12. Microarray analysis revealed that in addition to modulating many of the same DC maturation genes as LPS, galectin-1 also uniquely up-regulated a significant subset of genes related to cell migration through the extracellular matrix (ECM). Indeed, compared with LPS, galectin-1-treated human MDDCs exhibited significantly better chemotactic migration through Matrigel, an in vitro ECM model. Our findings show that galectin-1 is a novel endogenous activator of human MDDCs that up-regulates a significant subset of genes distinct from those regulated by a model exogenous stimulus (LPS). One unique effect of galectin-1 is to increase DC migration through the ECM, suggesting that galectin-1 may be an important component in initiating an immune response.
authors.affiliation: Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, University of California-Los Angeles, Los Angeles, CA 90095, USA.
authors.forename: Jennifer A
authors.initials: JA
authors.lastname: Fulcher
authors.forename: Sara T
authors.initials: ST
authors.lastname: Hashimi
authors.forename: Ernest L
authors.initials: EL
authors.lastname: Levroney
authors.forename: Mabel
authors.initials: M
authors.lastname: Pang
authors.forename: Kevin B
authors.initials: KB
authors.lastname: Gurney
authors.forename: Linda G
authors.initials: LG
authors.lastname: Baum
authors.forename: Benhur
authors.initials: B
authors.lastname: Lee
mesh_terms: D002454:Cell Differentiation / Q000235:genetics / Q000276:immunology*; D002462:Cell Membrane / Q000276:immunology / Q000378:metabolism; D002465:Cell Movement / Q000235:genetics / Q000276:immunology*; D002478:Cells, Cultured; D018920:Coculture Techniques; D016207:Cytokines / Q000378:metabolism; D003713:Dendritic Cells / Q000166:cytology* / Q000276:immunology / Q000378:metabolism*; D005109:Extracellular Matrix / Q000276:immunology* / Q000378:metabolism*; D037483:Galectin 1 / Q000378:metabolism / Q000502:physiology*; D005786:Gene Expression Regulation / Q000276:immunology; D006001:Glycoconjugates / Q000378:metabolism; D006801:Humans; D018796:Immunoconjugates / Q000378:metabolism; D016130:Immunophenotyping; D008070:Lipopolysaccharides / Q000494:pharmacology; D009000:Monocytes / Q000166:cytology* / Q000276:immunology / Q000378:metabolism; D011485:Protein Binding / Q000276:immunology; D016176:T-Lymphocyte Subsets / Q000166:cytology / Q000276:immunology / Q000378:metabolism; D015854:Up-Regulation / Q000235:genetics / Q000276:immunology
chemical_list: D016207:Cytokines; D037483:Galectin 1; D006001:Glycoconjugates; D018796:Immunoconjugates; D008070:Lipopolysaccharides