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Macrophage inflammatory protein 3alpha is involved in the constitutive trafficking of epidermal langerhans cells.

Charbonnier AS, Kohrgruber N, Kriehuber E, Stingl G, Rot A, Maurer D - J. Exp. Med. (1999)

Bottom Line: LCs lose the migratory responsiveness to MIP-3alpha during their maturation, and non-LC DCs do not acquire MIP-3alpha sensitivity.The notion that MIP-3alpha may be responsible for selective LC recruitment into the epidermis is further supported by the following observations: (a) MIP-3alpha is expressed by keratinocytes and venular endothelial cells in clinically normal appearing human skin; (b) LCs express CC chemokine receptor (CCR)6, the sole MIP-3alpha receptor both in situ and in vitro; and (c) non-LC DCs that are not found in normal epidermis lack CCR6.One type, the LC, responds to MIP-3alpha and enters skin to screen the epidermis constitutively, whereas the other type, the "inflammatory" DC, migrates in response to a wide array of different chemokines and is involved in the amplification and modulation of the inflammatory tissue response.

View Article: PubMed Central - PubMed

Affiliation: Division of Immunology, Department of Dermatology, University of Vienna Medical School, A-1090 Vienna, Austria.

ABSTRACT
Certain types of dendritic cells (DCs) appear in inflammatory lesions of various etiologies, whereas other DCs, e.g., Langerhans cells (LCs), populate peripheral organs constitutively. Until now, the molecular mechanism behind such differential behavior has not been elucidated. Here, we show that CD1a(+) LC precursors respond selectively and specifically to the CC chemokine macrophage inflammatory protein (MIP)-3alpha. In contrast, CD14(+) precursors of DC and monocytes are not attracted by MIP-3alpha. LCs lose the migratory responsiveness to MIP-3alpha during their maturation, and non-LC DCs do not acquire MIP-3alpha sensitivity. The notion that MIP-3alpha may be responsible for selective LC recruitment into the epidermis is further supported by the following observations: (a) MIP-3alpha is expressed by keratinocytes and venular endothelial cells in clinically normal appearing human skin; (b) LCs express CC chemokine receptor (CCR)6, the sole MIP-3alpha receptor both in situ and in vitro; and (c) non-LC DCs that are not found in normal epidermis lack CCR6. The mature forms of LCs and non-LC DCs display comparable sensitivity for MIP-3beta, a CCR7 ligand, suggesting that DC subtype-specific chemokine responses are restricted to the committed precursor stage. Although LC precursors express primarily CCR6, non-LC DC precursors display a broad chemokine receptor repertoire. These findings reflect a scenario where the differential expression of chemokine receptors by two different subpopulations of DCs determines their functional behavior. One type, the LC, responds to MIP-3alpha and enters skin to screen the epidermis constitutively, whereas the other type, the "inflammatory" DC, migrates in response to a wide array of different chemokines and is involved in the amplification and modulation of the inflammatory tissue response.

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MIP-1α and MIP-3α elicit different migratory and/or adhesive responses in CD34+ HPC-derived LC and DC precursors. Results shown in A and B were obtained using the transwell chemotaxis assay and the 48-well Boyden-type chamber chemotaxis assay, respectively. For both assays, day 6 LC and/or DC precursors were harvested and tested for their migratory responses to MIP-1α (filled circles), MIP-3α (open squares), and MIP-3β (open triangles). Mean percentages (± SEM) of migrated and detached (A; n = 3) and migrated, membrane-bound cells (B; n = 2) are shown. (C) Representative vertical sections through 5-μm pore size membranes used in the transwell chemotaxis assay. The assays were performed using the indicated stimuli (MIP-1α at 100 ng/ml, MIP-3α at 1 μg/ml, and the combination of both), or buffer alone. Membrane-bound cells were fixed and labeled, and membranes were subjected to confocal laser scanning microscopy. Broken lines denote the position of the membrane.
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Figure 2: MIP-1α and MIP-3α elicit different migratory and/or adhesive responses in CD34+ HPC-derived LC and DC precursors. Results shown in A and B were obtained using the transwell chemotaxis assay and the 48-well Boyden-type chamber chemotaxis assay, respectively. For both assays, day 6 LC and/or DC precursors were harvested and tested for their migratory responses to MIP-1α (filled circles), MIP-3α (open squares), and MIP-3β (open triangles). Mean percentages (± SEM) of migrated and detached (A; n = 3) and migrated, membrane-bound cells (B; n = 2) are shown. (C) Representative vertical sections through 5-μm pore size membranes used in the transwell chemotaxis assay. The assays were performed using the indicated stimuli (MIP-1α at 100 ng/ml, MIP-3α at 1 μg/ml, and the combination of both), or buffer alone. Membrane-bound cells were fixed and labeled, and membranes were subjected to confocal laser scanning microscopy. Broken lines denote the position of the membrane.

Mentions: In addition to being a selective chemoattractant for LC precursors, MIP-3α was the only chemokine in the panel tested that induced potent and efficacious migratory responses of these cells. LC precursors responded only weakly to SDF-1α and MIP-3β (Fig. 1C and Fig. D), and did not migrate at all in response to MCP-1, which, in contrast, attracted some CD14+ non-LC DC precursors (Fig. 1 B). Another chemoattraction profile was observed for the CD14− CD1a− cell population. As seen previously with HSCs, these cells were attracted by SDF-1α (Fig. 1 C 30) and responded to MCP-1 (Fig. 1 B), but not to MIP-3α or MIP-3β (Fig. 1A and Fig. D). As shown in Fig. 2 A, MIP-1α failed to induce migration of day 6 CD34+ HPC-derived DC precursors. The apparent lack of migratory response to this chemokine was surprising, since day 6 DC precursors express CCR1 and CCR5, both of which are receptors for MIP-1α (see below). The transwell migration assay used allows only the analysis of cells that have passed the membrane and detached into the lower chamber, whereas the cells that remain membrane bound escape detection. To control for the cells adherent to the lower side of the membrane, we also tested MIP-1α in the Boyden-type chamber assay, which detects the migrated, membrane-bound cells only. The direct comparison of the results obtained in these two migration assays, plus the analysis of the transwell membranes by confocal microscopy, showed that MIP-1α was eliciting migratory and/or adhesive responses in CD34+ HPC-derived DC precursors that were different from those induced by MIP-3α (Fig. 2A and Fig. B). In both the transwell and the Boyden-type assay, the cells that had been attracted by MIP-1α remained adherent to the membrane (Fig. 2B and Fig. C). In contrast, the cells that had responded to MIP-3α detached from the lower side of the membrane in the transwell system (Fig. 2 A) and remained membrane bound only in the Boyden-type assay (Fig. 2 B). The proadhesive effect of MIP-1α was pronounced also when an additional migration-inducing stimulus (e.g., MIP-3α) was provided at the same time (Fig. 2 C).


Macrophage inflammatory protein 3alpha is involved in the constitutive trafficking of epidermal langerhans cells.

Charbonnier AS, Kohrgruber N, Kriehuber E, Stingl G, Rot A, Maurer D - J. Exp. Med. (1999)

MIP-1α and MIP-3α elicit different migratory and/or adhesive responses in CD34+ HPC-derived LC and DC precursors. Results shown in A and B were obtained using the transwell chemotaxis assay and the 48-well Boyden-type chamber chemotaxis assay, respectively. For both assays, day 6 LC and/or DC precursors were harvested and tested for their migratory responses to MIP-1α (filled circles), MIP-3α (open squares), and MIP-3β (open triangles). Mean percentages (± SEM) of migrated and detached (A; n = 3) and migrated, membrane-bound cells (B; n = 2) are shown. (C) Representative vertical sections through 5-μm pore size membranes used in the transwell chemotaxis assay. The assays were performed using the indicated stimuli (MIP-1α at 100 ng/ml, MIP-3α at 1 μg/ml, and the combination of both), or buffer alone. Membrane-bound cells were fixed and labeled, and membranes were subjected to confocal laser scanning microscopy. Broken lines denote the position of the membrane.
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Related In: Results  -  Collection

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getmorefigures.php?uid=PMC2195721&req=5

Figure 2: MIP-1α and MIP-3α elicit different migratory and/or adhesive responses in CD34+ HPC-derived LC and DC precursors. Results shown in A and B were obtained using the transwell chemotaxis assay and the 48-well Boyden-type chamber chemotaxis assay, respectively. For both assays, day 6 LC and/or DC precursors were harvested and tested for their migratory responses to MIP-1α (filled circles), MIP-3α (open squares), and MIP-3β (open triangles). Mean percentages (± SEM) of migrated and detached (A; n = 3) and migrated, membrane-bound cells (B; n = 2) are shown. (C) Representative vertical sections through 5-μm pore size membranes used in the transwell chemotaxis assay. The assays were performed using the indicated stimuli (MIP-1α at 100 ng/ml, MIP-3α at 1 μg/ml, and the combination of both), or buffer alone. Membrane-bound cells were fixed and labeled, and membranes were subjected to confocal laser scanning microscopy. Broken lines denote the position of the membrane.
Mentions: In addition to being a selective chemoattractant for LC precursors, MIP-3α was the only chemokine in the panel tested that induced potent and efficacious migratory responses of these cells. LC precursors responded only weakly to SDF-1α and MIP-3β (Fig. 1C and Fig. D), and did not migrate at all in response to MCP-1, which, in contrast, attracted some CD14+ non-LC DC precursors (Fig. 1 B). Another chemoattraction profile was observed for the CD14− CD1a− cell population. As seen previously with HSCs, these cells were attracted by SDF-1α (Fig. 1 C 30) and responded to MCP-1 (Fig. 1 B), but not to MIP-3α or MIP-3β (Fig. 1A and Fig. D). As shown in Fig. 2 A, MIP-1α failed to induce migration of day 6 CD34+ HPC-derived DC precursors. The apparent lack of migratory response to this chemokine was surprising, since day 6 DC precursors express CCR1 and CCR5, both of which are receptors for MIP-1α (see below). The transwell migration assay used allows only the analysis of cells that have passed the membrane and detached into the lower chamber, whereas the cells that remain membrane bound escape detection. To control for the cells adherent to the lower side of the membrane, we also tested MIP-1α in the Boyden-type chamber assay, which detects the migrated, membrane-bound cells only. The direct comparison of the results obtained in these two migration assays, plus the analysis of the transwell membranes by confocal microscopy, showed that MIP-1α was eliciting migratory and/or adhesive responses in CD34+ HPC-derived DC precursors that were different from those induced by MIP-3α (Fig. 2A and Fig. B). In both the transwell and the Boyden-type assay, the cells that had been attracted by MIP-1α remained adherent to the membrane (Fig. 2B and Fig. C). In contrast, the cells that had responded to MIP-3α detached from the lower side of the membrane in the transwell system (Fig. 2 A) and remained membrane bound only in the Boyden-type assay (Fig. 2 B). The proadhesive effect of MIP-1α was pronounced also when an additional migration-inducing stimulus (e.g., MIP-3α) was provided at the same time (Fig. 2 C).

Bottom Line: LCs lose the migratory responsiveness to MIP-3alpha during their maturation, and non-LC DCs do not acquire MIP-3alpha sensitivity.The notion that MIP-3alpha may be responsible for selective LC recruitment into the epidermis is further supported by the following observations: (a) MIP-3alpha is expressed by keratinocytes and venular endothelial cells in clinically normal appearing human skin; (b) LCs express CC chemokine receptor (CCR)6, the sole MIP-3alpha receptor both in situ and in vitro; and (c) non-LC DCs that are not found in normal epidermis lack CCR6.One type, the LC, responds to MIP-3alpha and enters skin to screen the epidermis constitutively, whereas the other type, the "inflammatory" DC, migrates in response to a wide array of different chemokines and is involved in the amplification and modulation of the inflammatory tissue response.

View Article: PubMed Central - PubMed

Affiliation: Division of Immunology, Department of Dermatology, University of Vienna Medical School, A-1090 Vienna, Austria.

ABSTRACT
Certain types of dendritic cells (DCs) appear in inflammatory lesions of various etiologies, whereas other DCs, e.g., Langerhans cells (LCs), populate peripheral organs constitutively. Until now, the molecular mechanism behind such differential behavior has not been elucidated. Here, we show that CD1a(+) LC precursors respond selectively and specifically to the CC chemokine macrophage inflammatory protein (MIP)-3alpha. In contrast, CD14(+) precursors of DC and monocytes are not attracted by MIP-3alpha. LCs lose the migratory responsiveness to MIP-3alpha during their maturation, and non-LC DCs do not acquire MIP-3alpha sensitivity. The notion that MIP-3alpha may be responsible for selective LC recruitment into the epidermis is further supported by the following observations: (a) MIP-3alpha is expressed by keratinocytes and venular endothelial cells in clinically normal appearing human skin; (b) LCs express CC chemokine receptor (CCR)6, the sole MIP-3alpha receptor both in situ and in vitro; and (c) non-LC DCs that are not found in normal epidermis lack CCR6. The mature forms of LCs and non-LC DCs display comparable sensitivity for MIP-3beta, a CCR7 ligand, suggesting that DC subtype-specific chemokine responses are restricted to the committed precursor stage. Although LC precursors express primarily CCR6, non-LC DC precursors display a broad chemokine receptor repertoire. These findings reflect a scenario where the differential expression of chemokine receptors by two different subpopulations of DCs determines their functional behavior. One type, the LC, responds to MIP-3alpha and enters skin to screen the epidermis constitutively, whereas the other type, the "inflammatory" DC, migrates in response to a wide array of different chemokines and is involved in the amplification and modulation of the inflammatory tissue response.

Show MeSH
Related in: MedlinePlus