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Alpha 6 integrins are required for Langerhans cell migration from the epidermis.

Price AA, Cumberbatch M, Kimber I, Ager A - J. Exp. Med. (1997)

Bottom Line: RGD-containing peptides were also without effect on LC migration from skin explants.In contrast, alpha 4 integrins, or other integrin-dependent interactions with fibronectin that are mediated by the RGD recognition sequence, did not influence LC migration from the epidermis.In addition, alpha 4 integrins did not affect the accumulation of LCs as DCs in draining lymph nodes.

View Article: PubMed Central - PubMed

Affiliation: Division of Cellular Immunology, National Institute for Medical Research, London, United Kingdom.

ABSTRACT
Topical exposure of mice to chemical allergens results in the migration of epidermal Langerhans cells (LCs) from the skin and their accumulation as immunostimulatory dendritic cells (DCs) in draining lymph nodes. Epidermal cell-derived cytokines have been implicated in the maturation and migration of LCs, but the adhesion molecules that regulate LC migration have not been studied. We hypothesized that integrin-mediated interactions with extracellular matrix components of the skin and lymph node may regulate LC/DC migration. We found that alpha 6 integrins and alpha 4 integrins were differentially expressed by epidermal LCs and lymph node DCs. A majority of LCs (70%) expressed the alpha 6 integrin subunit, whereas DCs did not express alpha 6 integrins. In contrast, the alpha 4 integrin subunit was expressed at high levels on DCs but at much lower levels on LCs. The anti-alpha 6 integrin antibody, GoH3, which blocks binding to laminin, completely prevented the spontaneous migration of LCs from skin explants in vitro and the rapid migration of LCs from mouse ear skin induced after intradermal administration of TNF-alpha in vivo. GoH3 also reduced the accumulation of DCs in draining lymph nodes by a maximum of 70% after topical administration of the chemical allergen oxazolone. LCs remaining in the epidermis in the presence of GoH3 adopted a rounded morphology, rather than the interdigitating appearance typical of LCs in naive skin, suggesting that the cells had detached from neighboring keratinocytes and withdrawn cellular processes in preparation for migration, but were unable to leave the epidermis. The anti-alpha 4 integrin antibody PS/2, which blocks binding to fibronectin, had no effect on LC migration from the epidermis either in vitro or in vivo, or on the accumulation of DCs in draining lymph nodes after oxazolone application. RGD-containing peptides were also without effect on LC migration from skin explants. These results identify an important role for alpha 6 integrins in the migration of LC from the epidermis to the draining lymph node by regulating access across the epidermal basement membrane. In contrast, alpha 4 integrins, or other integrin-dependent interactions with fibronectin that are mediated by the RGD recognition sequence, did not influence LC migration from the epidermis. In addition, alpha 4 integrins did not affect the accumulation of LCs as DCs in draining lymph nodes.

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Immunohistochemical staining of epidermal LCs in situ. Epidermal sheets were prepared either from (A) naive mice, or from skin explants that had been incubated for 72 h on (B) culture medium containing  anti-α6 integrin antibody GoH3 at 50 μg/ml, or (C) culture medium  alone. LC are stained for MHC class II using indirect immunoperoxidase  staining. Note rounded morphology of LCs in anti-α6 integrin antibody– treated explants in comparison with interdigitating morphology of LCs in  naive skin. Magnification, ×600.
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Figure 3: Immunohistochemical staining of epidermal LCs in situ. Epidermal sheets were prepared either from (A) naive mice, or from skin explants that had been incubated for 72 h on (B) culture medium containing anti-α6 integrin antibody GoH3 at 50 μg/ml, or (C) culture medium alone. LC are stained for MHC class II using indirect immunoperoxidase staining. Note rounded morphology of LCs in anti-α6 integrin antibody– treated explants in comparison with interdigitating morphology of LCs in naive skin. Magnification, ×600.

Mentions: Inclusion of 100 μg/ml anti-α6 antibody (GoH3) in the medium completely prevented the emigration of LCs from skin explants over a 72-h period. The number of LCs/mm2 remaining in the epidermis (1,193 ± 174) was similar to that in fresh epidermis (1,168 ± 87). Lower doses of GoH3, down to 10 μg/ml, also substantially inhibited LC migration. The morphology of LCs remaining in the epidermis of anti-α6 integrin antibody–treated explants differed significantly from that of LCs in fresh epidermis (Fig. 3). LCs in α6 integrin antibody–treated skin explants were rounded in appearance and lacked the interdigitating cellular processes typical of LCs in naive skin. The few LCs remaining in skin explants incubated either in the complete absence of antibody or in the presence of isotype-matched control antibody showed similar morphologies; LCs were slightly larger than in naive skin and showed a reduced number of interdigitating processes. The staining for MHC class II on LCs in α6 integrin antibody–treated skin and in control skin explants was more intense than that on LCs in fresh epidermal sheets.


Alpha 6 integrins are required for Langerhans cell migration from the epidermis.

Price AA, Cumberbatch M, Kimber I, Ager A - J. Exp. Med. (1997)

Immunohistochemical staining of epidermal LCs in situ. Epidermal sheets were prepared either from (A) naive mice, or from skin explants that had been incubated for 72 h on (B) culture medium containing  anti-α6 integrin antibody GoH3 at 50 μg/ml, or (C) culture medium  alone. LC are stained for MHC class II using indirect immunoperoxidase  staining. Note rounded morphology of LCs in anti-α6 integrin antibody– treated explants in comparison with interdigitating morphology of LCs in  naive skin. Magnification, ×600.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2199129&req=5

Figure 3: Immunohistochemical staining of epidermal LCs in situ. Epidermal sheets were prepared either from (A) naive mice, or from skin explants that had been incubated for 72 h on (B) culture medium containing anti-α6 integrin antibody GoH3 at 50 μg/ml, or (C) culture medium alone. LC are stained for MHC class II using indirect immunoperoxidase staining. Note rounded morphology of LCs in anti-α6 integrin antibody– treated explants in comparison with interdigitating morphology of LCs in naive skin. Magnification, ×600.
Mentions: Inclusion of 100 μg/ml anti-α6 antibody (GoH3) in the medium completely prevented the emigration of LCs from skin explants over a 72-h period. The number of LCs/mm2 remaining in the epidermis (1,193 ± 174) was similar to that in fresh epidermis (1,168 ± 87). Lower doses of GoH3, down to 10 μg/ml, also substantially inhibited LC migration. The morphology of LCs remaining in the epidermis of anti-α6 integrin antibody–treated explants differed significantly from that of LCs in fresh epidermis (Fig. 3). LCs in α6 integrin antibody–treated skin explants were rounded in appearance and lacked the interdigitating cellular processes typical of LCs in naive skin. The few LCs remaining in skin explants incubated either in the complete absence of antibody or in the presence of isotype-matched control antibody showed similar morphologies; LCs were slightly larger than in naive skin and showed a reduced number of interdigitating processes. The staining for MHC class II on LCs in α6 integrin antibody–treated skin and in control skin explants was more intense than that on LCs in fresh epidermal sheets.

Bottom Line: RGD-containing peptides were also without effect on LC migration from skin explants.In contrast, alpha 4 integrins, or other integrin-dependent interactions with fibronectin that are mediated by the RGD recognition sequence, did not influence LC migration from the epidermis.In addition, alpha 4 integrins did not affect the accumulation of LCs as DCs in draining lymph nodes.

View Article: PubMed Central - PubMed

Affiliation: Division of Cellular Immunology, National Institute for Medical Research, London, United Kingdom.

ABSTRACT
Topical exposure of mice to chemical allergens results in the migration of epidermal Langerhans cells (LCs) from the skin and their accumulation as immunostimulatory dendritic cells (DCs) in draining lymph nodes. Epidermal cell-derived cytokines have been implicated in the maturation and migration of LCs, but the adhesion molecules that regulate LC migration have not been studied. We hypothesized that integrin-mediated interactions with extracellular matrix components of the skin and lymph node may regulate LC/DC migration. We found that alpha 6 integrins and alpha 4 integrins were differentially expressed by epidermal LCs and lymph node DCs. A majority of LCs (70%) expressed the alpha 6 integrin subunit, whereas DCs did not express alpha 6 integrins. In contrast, the alpha 4 integrin subunit was expressed at high levels on DCs but at much lower levels on LCs. The anti-alpha 6 integrin antibody, GoH3, which blocks binding to laminin, completely prevented the spontaneous migration of LCs from skin explants in vitro and the rapid migration of LCs from mouse ear skin induced after intradermal administration of TNF-alpha in vivo. GoH3 also reduced the accumulation of DCs in draining lymph nodes by a maximum of 70% after topical administration of the chemical allergen oxazolone. LCs remaining in the epidermis in the presence of GoH3 adopted a rounded morphology, rather than the interdigitating appearance typical of LCs in naive skin, suggesting that the cells had detached from neighboring keratinocytes and withdrawn cellular processes in preparation for migration, but were unable to leave the epidermis. The anti-alpha 4 integrin antibody PS/2, which blocks binding to fibronectin, had no effect on LC migration from the epidermis either in vitro or in vivo, or on the accumulation of DCs in draining lymph nodes after oxazolone application. RGD-containing peptides were also without effect on LC migration from skin explants. These results identify an important role for alpha 6 integrins in the migration of LC from the epidermis to the draining lymph node by regulating access across the epidermal basement membrane. In contrast, alpha 4 integrins, or other integrin-dependent interactions with fibronectin that are mediated by the RGD recognition sequence, did not influence LC migration from the epidermis. In addition, alpha 4 integrins did not affect the accumulation of LCs as DCs in draining lymph nodes.

Show MeSH
Related in: MedlinePlus