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Galectin-2 induces a proinflammatory, anti-arteriogenic phenotype in monocytes and macrophages.

Yıldırım C, Vogel DY, Hollander MR, Baggen JM, Fontijn RD, Nieuwenhuis S, Haverkamp A, de Vries MR, Quax PH, Garcia-Vallejo JJ, van der Laan AM, Dijkstra CD, van der Pouw Kraan TC, van Royen N, Horrevoets AJ - PLoS ONE (2015)

Bottom Line: The inhibiting effect of galectin-2 on arteriogenesis was confirmed in vivo, but the mechanism is largely unknown.Furthermore, galectin-2 skews human macrophages to a M1-like proinflammatory phenotype, characterized by a reduced motility and expression of an anti-arteriogenic cytokine/growth factor repertoire.This is accompanied by a switch in surface protein expression to CD40-high and CD206-low (M1).

View Article: PubMed Central - PubMed

Affiliation: Dept of Molecular Cell Biology and Immunology, VU University Medical Centre, Amsterdam, the Netherlands.

ABSTRACT
Galectin-2 is a monocyte-expressed carbohydrate-binding lectin, for which increased expression is genetically determined and associated with decreased collateral arteriogenesis in obstructive coronary artery disease patients. The inhibiting effect of galectin-2 on arteriogenesis was confirmed in vivo, but the mechanism is largely unknown. In this study we aimed to explore the effects of galectin-2 on monocyte/macrophage phenotype in vitro and vivo, and to identify the receptor by which galectin-2 exerts these effects. We now show that the binding of galectin-2 to different circulating human monocyte subsets is dependent on monocyte surface expression levels of CD14. The high affinity binding is blocked by an anti-CD14 antibody but not by carbohydrates, indicating a specific protein-protein interaction. Galectin-2 binding to human monocytes modulated their transcriptome by inducing proinflammatory cytokines and inhibiting pro-arteriogenic factors, while attenuating monocyte migration. Using specific knock-out mice, we show that galectin-2 acts through the CD14/toll-like receptor (TLR)-4 pathway. Furthermore, galectin-2 skews human macrophages to a M1-like proinflammatory phenotype, characterized by a reduced motility and expression of an anti-arteriogenic cytokine/growth factor repertoire. This is accompanied by a switch in surface protein expression to CD40-high and CD206-low (M1). In a murine model we show that galectin-2 administration, known to attenuate arteriogenesis, leads to increased numbers of CD40-positive (M1) and reduced numbers of CD206-positive (M2) macrophages surrounding actively remodeling collateral arteries. In conclusion galectin-2 is the first endogenous CD14/TLR4 ligand that induces a proinflammatory, non-arteriogenic phenotype in monocytes/macrophages. Interference with CD14-Galectin-2 interaction may provide a new intervention strategy to stimulate growth of collateral arteries in genetically compromised cardiovascular patients.

No MeSH data available.


Related in: MedlinePlus

Human galectin-2 treatment induces M1 polarization of macrophages in vivo.(A) Representative immunofluorescence staining of CD40/F4-80 (M1) and CD206/F4-80 (M2) macrophages on muscle sections of the left adductor of the ligated hind limb obtained from placebo and human galectin-2 treated mice at 7 days after occlusion of the femoral artery is shown.Photomicrographs show arteries identified by SMA (yellow; Alexa fluor 488), cell nucleus by Hoechst (blue), macrophages by F4/80 (red; Alexa fluor 647) and macrophage subtypes by CD40 (green; streptavidin Alexa fluor 555) or CD206 (green; streptavidin Alexa fluor 555) staining as described in methods. Arrowheads indicate the macrophage subtypes. (B) Boxplot showing the counts of M1 and M2 macrophages in placebo vs. human galectin-2 treated mice. Data are presented as median and range. Boxes represent the first and third quartiles, the line within the box represents the median, and the lines outside the box represent the spread of the values. N = 7 for placebo, N = 5 for human galectin-2 treated group. (**P < 0.01, Mann-Whitney U test).
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pone.0124347.g007: Human galectin-2 treatment induces M1 polarization of macrophages in vivo.(A) Representative immunofluorescence staining of CD40/F4-80 (M1) and CD206/F4-80 (M2) macrophages on muscle sections of the left adductor of the ligated hind limb obtained from placebo and human galectin-2 treated mice at 7 days after occlusion of the femoral artery is shown.Photomicrographs show arteries identified by SMA (yellow; Alexa fluor 488), cell nucleus by Hoechst (blue), macrophages by F4/80 (red; Alexa fluor 647) and macrophage subtypes by CD40 (green; streptavidin Alexa fluor 555) or CD206 (green; streptavidin Alexa fluor 555) staining as described in methods. Arrowheads indicate the macrophage subtypes. (B) Boxplot showing the counts of M1 and M2 macrophages in placebo vs. human galectin-2 treated mice. Data are presented as median and range. Boxes represent the first and third quartiles, the line within the box represents the median, and the lines outside the box represent the spread of the values. N = 7 for placebo, N = 5 for human galectin-2 treated group. (**P < 0.01, Mann-Whitney U test).

Mentions: We previously showed that systemic administration of galectin-2 inhibits arteriogenesis after arterial ligation in the murine hind limb model [11]. Diminished arteriogenesis, as detected by Laser Doppler Perfusion Analysis and histology, was accompanied by a reduced number of macrophages surrounding the collateral vessels in the adductor muscle. We now used tissue sections from this study to assess the effect of human galectin-2 treatment on the presence of M1 and M2 macrophages around the collateral arteries in vivo by immunohistochemistry.M1-like macrophages were defined here as CD40+ F4/80+-positive cells while M2-like macrophages were detected as CD206+ F4/80+-cells, in close proximity to actively remodeling collateral arteries in the adductor muscle. This revealed that the number of M1 macrophages was significantly increased (24%) in mice treated with galectin-2 compared to placebo-treated mice. Furthermore, the number of M2 macrophages showed a significant decrease by 40% following galectin-2 treatment compared to placebo-treated mice (Fig 7). These results indicate that galectin-2 treatment in vivo promotes M1 and inhibits M2 macrophage accumulation during expansive arterial remodeling.


Galectin-2 induces a proinflammatory, anti-arteriogenic phenotype in monocytes and macrophages.

Yıldırım C, Vogel DY, Hollander MR, Baggen JM, Fontijn RD, Nieuwenhuis S, Haverkamp A, de Vries MR, Quax PH, Garcia-Vallejo JJ, van der Laan AM, Dijkstra CD, van der Pouw Kraan TC, van Royen N, Horrevoets AJ - PLoS ONE (2015)

Human galectin-2 treatment induces M1 polarization of macrophages in vivo.(A) Representative immunofluorescence staining of CD40/F4-80 (M1) and CD206/F4-80 (M2) macrophages on muscle sections of the left adductor of the ligated hind limb obtained from placebo and human galectin-2 treated mice at 7 days after occlusion of the femoral artery is shown.Photomicrographs show arteries identified by SMA (yellow; Alexa fluor 488), cell nucleus by Hoechst (blue), macrophages by F4/80 (red; Alexa fluor 647) and macrophage subtypes by CD40 (green; streptavidin Alexa fluor 555) or CD206 (green; streptavidin Alexa fluor 555) staining as described in methods. Arrowheads indicate the macrophage subtypes. (B) Boxplot showing the counts of M1 and M2 macrophages in placebo vs. human galectin-2 treated mice. Data are presented as median and range. Boxes represent the first and third quartiles, the line within the box represents the median, and the lines outside the box represent the spread of the values. N = 7 for placebo, N = 5 for human galectin-2 treated group. (**P < 0.01, Mann-Whitney U test).
© Copyright Policy
Related In: Results  -  Collection

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Show All Figures
getmorefigures.php?uid=PMC4401781&req=5

pone.0124347.g007: Human galectin-2 treatment induces M1 polarization of macrophages in vivo.(A) Representative immunofluorescence staining of CD40/F4-80 (M1) and CD206/F4-80 (M2) macrophages on muscle sections of the left adductor of the ligated hind limb obtained from placebo and human galectin-2 treated mice at 7 days after occlusion of the femoral artery is shown.Photomicrographs show arteries identified by SMA (yellow; Alexa fluor 488), cell nucleus by Hoechst (blue), macrophages by F4/80 (red; Alexa fluor 647) and macrophage subtypes by CD40 (green; streptavidin Alexa fluor 555) or CD206 (green; streptavidin Alexa fluor 555) staining as described in methods. Arrowheads indicate the macrophage subtypes. (B) Boxplot showing the counts of M1 and M2 macrophages in placebo vs. human galectin-2 treated mice. Data are presented as median and range. Boxes represent the first and third quartiles, the line within the box represents the median, and the lines outside the box represent the spread of the values. N = 7 for placebo, N = 5 for human galectin-2 treated group. (**P < 0.01, Mann-Whitney U test).
Mentions: We previously showed that systemic administration of galectin-2 inhibits arteriogenesis after arterial ligation in the murine hind limb model [11]. Diminished arteriogenesis, as detected by Laser Doppler Perfusion Analysis and histology, was accompanied by a reduced number of macrophages surrounding the collateral vessels in the adductor muscle. We now used tissue sections from this study to assess the effect of human galectin-2 treatment on the presence of M1 and M2 macrophages around the collateral arteries in vivo by immunohistochemistry.M1-like macrophages were defined here as CD40+ F4/80+-positive cells while M2-like macrophages were detected as CD206+ F4/80+-cells, in close proximity to actively remodeling collateral arteries in the adductor muscle. This revealed that the number of M1 macrophages was significantly increased (24%) in mice treated with galectin-2 compared to placebo-treated mice. Furthermore, the number of M2 macrophages showed a significant decrease by 40% following galectin-2 treatment compared to placebo-treated mice (Fig 7). These results indicate that galectin-2 treatment in vivo promotes M1 and inhibits M2 macrophage accumulation during expansive arterial remodeling.

Bottom Line: The inhibiting effect of galectin-2 on arteriogenesis was confirmed in vivo, but the mechanism is largely unknown.Furthermore, galectin-2 skews human macrophages to a M1-like proinflammatory phenotype, characterized by a reduced motility and expression of an anti-arteriogenic cytokine/growth factor repertoire.This is accompanied by a switch in surface protein expression to CD40-high and CD206-low (M1).

View Article: PubMed Central - PubMed

Affiliation: Dept of Molecular Cell Biology and Immunology, VU University Medical Centre, Amsterdam, the Netherlands.

ABSTRACT
Galectin-2 is a monocyte-expressed carbohydrate-binding lectin, for which increased expression is genetically determined and associated with decreased collateral arteriogenesis in obstructive coronary artery disease patients. The inhibiting effect of galectin-2 on arteriogenesis was confirmed in vivo, but the mechanism is largely unknown. In this study we aimed to explore the effects of galectin-2 on monocyte/macrophage phenotype in vitro and vivo, and to identify the receptor by which galectin-2 exerts these effects. We now show that the binding of galectin-2 to different circulating human monocyte subsets is dependent on monocyte surface expression levels of CD14. The high affinity binding is blocked by an anti-CD14 antibody but not by carbohydrates, indicating a specific protein-protein interaction. Galectin-2 binding to human monocytes modulated their transcriptome by inducing proinflammatory cytokines and inhibiting pro-arteriogenic factors, while attenuating monocyte migration. Using specific knock-out mice, we show that galectin-2 acts through the CD14/toll-like receptor (TLR)-4 pathway. Furthermore, galectin-2 skews human macrophages to a M1-like proinflammatory phenotype, characterized by a reduced motility and expression of an anti-arteriogenic cytokine/growth factor repertoire. This is accompanied by a switch in surface protein expression to CD40-high and CD206-low (M1). In a murine model we show that galectin-2 administration, known to attenuate arteriogenesis, leads to increased numbers of CD40-positive (M1) and reduced numbers of CD206-positive (M2) macrophages surrounding actively remodeling collateral arteries. In conclusion galectin-2 is the first endogenous CD14/TLR4 ligand that induces a proinflammatory, non-arteriogenic phenotype in monocytes/macrophages. Interference with CD14-Galectin-2 interaction may provide a new intervention strategy to stimulate growth of collateral arteries in genetically compromised cardiovascular patients.

No MeSH data available.


Related in: MedlinePlus