Limits...
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appearance typical of LCs in naive skin, suggesting that the cells had detached from neighboring keratinocytes and withdrawn cellular processes in preparation for migration, but were unable to leave the epidermis.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.

Show MeSH

Related in: MedlinePlus

The effect of anti-α6  integrin antibody EA-1 and  GRGDS peptide on the migration of epidermal LCs in vitro.  Skin explants were incubated on  culture medium containing: (A)  50 μg/ml EA-1 (solid bars) or  control antibody (hatched bars);  (B) 500 μM GRGDS (RGD;  solid bars) or GRDGS (RDG;  hatched bars). Additional controls  included explants incubated on  medium containing no antibody  (open bars). The number of LCs/ mm2 was determined after 24  and 72 h of incubation and compared with fresh skin (0 h). Results are expressed as means ±  SD (n = 18). Treatment of explant cultures with EA-1 antibody failed to cause a significant  increase in the frequency of LCs  at 24 or 72 h compared with cultures containing no antibody or  an isotype-matched control antibody (A). Addition to explant  cultures of GRGDS also failed to  cause a significant increase in the  frequency of LCs at 24 or 72 h  compared with cultures containing no peptide or GRDGS.
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC2199129&req=5

Figure 4: The effect of anti-α6 integrin antibody EA-1 and GRGDS peptide on the migration of epidermal LCs in vitro. Skin explants were incubated on culture medium containing: (A) 50 μg/ml EA-1 (solid bars) or control antibody (hatched bars); (B) 500 μM GRGDS (RGD; solid bars) or GRDGS (RDG; hatched bars). Additional controls included explants incubated on medium containing no antibody (open bars). The number of LCs/ mm2 was determined after 24 and 72 h of incubation and compared with fresh skin (0 h). Results are expressed as means ± SD (n = 18). Treatment of explant cultures with EA-1 antibody failed to cause a significant increase in the frequency of LCs at 24 or 72 h compared with cultures containing no antibody or an isotype-matched control antibody (A). Addition to explant cultures of GRGDS also failed to cause a significant increase in the frequency of LCs at 24 or 72 h compared with cultures containing no peptide or GRDGS.

Mentions: The mAb EA-1 recognizes the α6 integrin subunit and has been shown to inhibit α6 integrin–mediated binding of prothymocytes to thymic blood vessels in mice (19). However, unlike GoH3, it does not block the interaction of α6 integrins with laminin, suggesting that α6 integrins have an alternative ligand to laminin (20). Skin explants were incubated on culture medium containing ⩽50 μg/ml EA-1 and the number of LCs was determined after 24 and 72 h (Fig. 4). In contrast to the effects of GoH3, the EA-1 antibody had no effect on the migration of LCs from skin explants even after 72 h of incubation.


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

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

The effect of anti-α6  integrin antibody EA-1 and  GRGDS peptide on the migration of epidermal LCs in vitro.  Skin explants were incubated on  culture medium containing: (A)  50 μg/ml EA-1 (solid bars) or  control antibody (hatched bars);  (B) 500 μM GRGDS (RGD;  solid bars) or GRDGS (RDG;  hatched bars). Additional controls  included explants incubated on  medium containing no antibody  (open bars). The number of LCs/ mm2 was determined after 24  and 72 h of incubation and compared with fresh skin (0 h). Results are expressed as means ±  SD (n = 18). Treatment of explant cultures with EA-1 antibody failed to cause a significant  increase in the frequency of LCs  at 24 or 72 h compared with cultures containing no antibody or  an isotype-matched control antibody (A). Addition to explant  cultures of GRGDS also failed to  cause a significant increase in the  frequency of LCs at 24 or 72 h  compared with cultures containing no peptide or GRDGS.
© Copyright Policy
Related In: Results  -  Collection

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

Figure 4: The effect of anti-α6 integrin antibody EA-1 and GRGDS peptide on the migration of epidermal LCs in vitro. Skin explants were incubated on culture medium containing: (A) 50 μg/ml EA-1 (solid bars) or control antibody (hatched bars); (B) 500 μM GRGDS (RGD; solid bars) or GRDGS (RDG; hatched bars). Additional controls included explants incubated on medium containing no antibody (open bars). The number of LCs/ mm2 was determined after 24 and 72 h of incubation and compared with fresh skin (0 h). Results are expressed as means ± SD (n = 18). Treatment of explant cultures with EA-1 antibody failed to cause a significant increase in the frequency of LCs at 24 or 72 h compared with cultures containing no antibody or an isotype-matched control antibody (A). Addition to explant cultures of GRGDS also failed to cause a significant increase in the frequency of LCs at 24 or 72 h compared with cultures containing no peptide or GRDGS.
Mentions: The mAb EA-1 recognizes the α6 integrin subunit and has been shown to inhibit α6 integrin–mediated binding of prothymocytes to thymic blood vessels in mice (19). However, unlike GoH3, it does not block the interaction of α6 integrins with laminin, suggesting that α6 integrins have an alternative ligand to laminin (20). Skin explants were incubated on culture medium containing ⩽50 μg/ml EA-1 and the number of LCs was determined after 24 and 72 h (Fig. 4). In contrast to the effects of GoH3, the EA-1 antibody had no effect on the migration of LCs from skin explants even after 72 h of incubation.

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