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Polarization of chemokine receptors to the leading edge during lymphocyte chemotaxis.

Nieto M, Frade JM, Sancho D, Mellado M, Martinez-A C, Sánchez-Madrid F - J. Exp. Med. (1997)

Bottom Line: In this study, we demonstrate that the CC chemokine receptors CCR2 and CCR5, but not cytokine receptors such as interleukin (IL)-2Ralpha, IL-2Rbeta, tumor necrosis factor receptor 1, or transforming growth factor betaR, are redistributed to a pole in T cells that are migrating in response to chemokines.Immunofluorescence and confocal microscopy studies show that the chemokine receptors concentrate at the leading edge of the cell on the flattened cell-substratum contact area, induced specifically by the signals that trigger cell polarization.The redistribution of chemokine receptors is blocked by pertussis toxin and is dependent on cell adhesion through integrin receptors, which mediate cell migration.

View Article: PubMed Central - PubMed

Affiliation: Servicio de Inmunología, Hospital de la Princesa, Universidad Autónoma de Madrid, E-28006, Madrid, Spain.

ABSTRACT
Leukocyte migration in response to cell attractant gradients or chemotaxis is a key phenomenon both in cell movement and in the inflammatory response. Chemokines are quite likely to be the key molecules directing migration of leukocytes that involve cell polarization with generation of specialized cell compartments. The precise mechanism of leukocyte chemoattraction is not known, however. In this study, we demonstrate that the CC chemokine receptors CCR2 and CCR5, but not cytokine receptors such as interleukin (IL)-2Ralpha, IL-2Rbeta, tumor necrosis factor receptor 1, or transforming growth factor betaR, are redistributed to a pole in T cells that are migrating in response to chemokines. Immunofluorescence and confocal microscopy studies show that the chemokine receptors concentrate at the leading edge of the cell on the flattened cell-substratum contact area, induced specifically by the signals that trigger cell polarization. The redistribution of chemokine receptors is blocked by pertussis toxin and is dependent on cell adhesion through integrin receptors, which mediate cell migration. Chemokine receptor expression on the leading edge of migrating polarized lymphocytes appears to act as a sensor mechanism for the directed migration of leukocytes through a chemoattractant gradient.

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The CCR2 and the  CCR5 receptors redistribute to  the leading edge of the polarized  migrating T cells. PHA-activated  T lymphocytes, untreated (A and  C), or treated with 10 ng/ml  MCP-1 (B) or 10 ng/ml  RANTES (D), were allowed to  adhere to coverslips coated with  20 μg/ml FN-80 (A and B) or  10 μg/ml rsICAM-1-Fc (C and  D), and then fixed and stained  with the anti-CCR2 mAb  MCP-1R03 (A and B) or the  anti-CCR5 mouse antiserum (C  and D), as described in Materials  and Methods. Cells were photographed under epifluorescent  conditions. Original magnification: ×1,200. Bar, 10 μm. Insets  show staining of the IL-2Rα  with the TP1/6 mAb on a resting (A) and a polarized (B) T  lymphoblast. Original magnification: ×600.
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Figure 2: The CCR2 and the CCR5 receptors redistribute to the leading edge of the polarized migrating T cells. PHA-activated T lymphocytes, untreated (A and C), or treated with 10 ng/ml MCP-1 (B) or 10 ng/ml RANTES (D), were allowed to adhere to coverslips coated with 20 μg/ml FN-80 (A and B) or 10 μg/ml rsICAM-1-Fc (C and D), and then fixed and stained with the anti-CCR2 mAb MCP-1R03 (A and B) or the anti-CCR5 mouse antiserum (C and D), as described in Materials and Methods. Cells were photographed under epifluorescent conditions. Original magnification: ×1,200. Bar, 10 μm. Insets show staining of the IL-2Rα with the TP1/6 mAb on a resting (A) and a polarized (B) T lymphoblast. Original magnification: ×600.

Mentions: Cell migration directed by chemical attractant gradients requires cell polarization, but the fine mechanism by which this directional response is achieved remains to be described (8, 9, 16, 17). We studied the cellular distribution of chemokine receptors during T lymphocyte migration. CCR2 and CCR5 were evenly distributed throughout the T lymphoblast cell membrane (Fig. 2, A and C). Upon incubation of T lymphoblasts with MCP-1 or RANTES, a rapid cell polarization takes place that results in the redistribution of CCR2 and CCR5 receptors to the leading edge of the cell (Fig. 2, B and D). In the presence of a chemokine gradient, the cluster of CCR2 was clearly oriented towards the chemoattractant source. Parallel videomicroscopy studies showed that polarized cells correspond to migrating cells (Fig. 3). IL-2Rα, IL-2Rβ, TNFRI, and TGF-β type II receptor expression was also analyzed and found to undergo neither redistribution nor clustering during polarization (Fig. 2, A and B, insets, and data not shown).


Polarization of chemokine receptors to the leading edge during lymphocyte chemotaxis.

Nieto M, Frade JM, Sancho D, Mellado M, Martinez-A C, Sánchez-Madrid F - J. Exp. Med. (1997)

The CCR2 and the  CCR5 receptors redistribute to  the leading edge of the polarized  migrating T cells. PHA-activated  T lymphocytes, untreated (A and  C), or treated with 10 ng/ml  MCP-1 (B) or 10 ng/ml  RANTES (D), were allowed to  adhere to coverslips coated with  20 μg/ml FN-80 (A and B) or  10 μg/ml rsICAM-1-Fc (C and  D), and then fixed and stained  with the anti-CCR2 mAb  MCP-1R03 (A and B) or the  anti-CCR5 mouse antiserum (C  and D), as described in Materials  and Methods. Cells were photographed under epifluorescent  conditions. Original magnification: ×1,200. Bar, 10 μm. Insets  show staining of the IL-2Rα  with the TP1/6 mAb on a resting (A) and a polarized (B) T  lymphoblast. Original magnification: ×600.
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Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2198956&req=5

Figure 2: The CCR2 and the CCR5 receptors redistribute to the leading edge of the polarized migrating T cells. PHA-activated T lymphocytes, untreated (A and C), or treated with 10 ng/ml MCP-1 (B) or 10 ng/ml RANTES (D), were allowed to adhere to coverslips coated with 20 μg/ml FN-80 (A and B) or 10 μg/ml rsICAM-1-Fc (C and D), and then fixed and stained with the anti-CCR2 mAb MCP-1R03 (A and B) or the anti-CCR5 mouse antiserum (C and D), as described in Materials and Methods. Cells were photographed under epifluorescent conditions. Original magnification: ×1,200. Bar, 10 μm. Insets show staining of the IL-2Rα with the TP1/6 mAb on a resting (A) and a polarized (B) T lymphoblast. Original magnification: ×600.
Mentions: Cell migration directed by chemical attractant gradients requires cell polarization, but the fine mechanism by which this directional response is achieved remains to be described (8, 9, 16, 17). We studied the cellular distribution of chemokine receptors during T lymphocyte migration. CCR2 and CCR5 were evenly distributed throughout the T lymphoblast cell membrane (Fig. 2, A and C). Upon incubation of T lymphoblasts with MCP-1 or RANTES, a rapid cell polarization takes place that results in the redistribution of CCR2 and CCR5 receptors to the leading edge of the cell (Fig. 2, B and D). In the presence of a chemokine gradient, the cluster of CCR2 was clearly oriented towards the chemoattractant source. Parallel videomicroscopy studies showed that polarized cells correspond to migrating cells (Fig. 3). IL-2Rα, IL-2Rβ, TNFRI, and TGF-β type II receptor expression was also analyzed and found to undergo neither redistribution nor clustering during polarization (Fig. 2, A and B, insets, and data not shown).

Bottom Line: In this study, we demonstrate that the CC chemokine receptors CCR2 and CCR5, but not cytokine receptors such as interleukin (IL)-2Ralpha, IL-2Rbeta, tumor necrosis factor receptor 1, or transforming growth factor betaR, are redistributed to a pole in T cells that are migrating in response to chemokines.Immunofluorescence and confocal microscopy studies show that the chemokine receptors concentrate at the leading edge of the cell on the flattened cell-substratum contact area, induced specifically by the signals that trigger cell polarization.The redistribution of chemokine receptors is blocked by pertussis toxin and is dependent on cell adhesion through integrin receptors, which mediate cell migration.

View Article: PubMed Central - PubMed

Affiliation: Servicio de Inmunología, Hospital de la Princesa, Universidad Autónoma de Madrid, E-28006, Madrid, Spain.

ABSTRACT
Leukocyte migration in response to cell attractant gradients or chemotaxis is a key phenomenon both in cell movement and in the inflammatory response. Chemokines are quite likely to be the key molecules directing migration of leukocytes that involve cell polarization with generation of specialized cell compartments. The precise mechanism of leukocyte chemoattraction is not known, however. In this study, we demonstrate that the CC chemokine receptors CCR2 and CCR5, but not cytokine receptors such as interleukin (IL)-2Ralpha, IL-2Rbeta, tumor necrosis factor receptor 1, or transforming growth factor betaR, are redistributed to a pole in T cells that are migrating in response to chemokines. Immunofluorescence and confocal microscopy studies show that the chemokine receptors concentrate at the leading edge of the cell on the flattened cell-substratum contact area, induced specifically by the signals that trigger cell polarization. The redistribution of chemokine receptors is blocked by pertussis toxin and is dependent on cell adhesion through integrin receptors, which mediate cell migration. Chemokine receptor expression on the leading edge of migrating polarized lymphocytes appears to act as a sensor mechanism for the directed migration of leukocytes through a chemoattractant gradient.

Show MeSH
Related in: MedlinePlus