Abstract
After exposure to antigen, Langerhans cells (LC) migrate from the epidermis to lymph nodes, where they initiate primary immune responses in T cells. The adhesion molecule E-cadherin mediates adhesion of LC to keratinocytes in vitro and may be responsible for localization of LC in epidermis. To determine? if levels of LC E-cadherin are modulated during LC emigration from epidermis, we utilized how cytometry to evaluate E-cadherin expression on BALB/c LC exposed in situ to the contact allergen 2,4,6-trinitrochlorobenzene (TNCB). TNCB induced increased I-A/E antigen and decreased E-cadherin expression on a subpopulation of LC as early as 12 h, and as late as 48 h, after application. At 24 h, ~ 30% of LC in TNCB-treated skin expressed increased I-A/E antigens; of these activated LC, ~ 40% expressed decreased levels of E-cadherin. E-cadherin levels on this latter subset were ~ 15% of those expressed by LC in normal skin, and were similar to levels on cultured LC and LC that migrated from skin explants. The effect was specific for allergens; no changes occurred in LC following treatment with several contact irritants or the tolerogen dinitrathiocyanobenzene. To determine if cytokines modulated LC E-cadherin expression, we introduced various cytokines into BALB/c ear skin and assayed I-A/E antigen and E-cadherin levels. Of the cytokines tested, only interleukin-1 and tumor necrosis factor a reproduced the effects of TNCB. We propose that downmodulation of E-cadherin expression occurs as a consequence of local cytokine production during antigen-induced LC activation, facilitating LC emigration and the initiation of immune responses against antigens encountered in epidermis.
Original language | English (US) |
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Pages (from-to) | 553-558 |
Number of pages | 6 |
Journal | Journal of Investigative Dermatology |
Volume | 106 |
Issue number | 3 |
DOIs | |
State | Published - 1996 |
Externally published | Yes |
Keywords
- Activation
- Adhesion
- Leukocyte
- Migration
ASJC Scopus subject areas
- Biochemistry
- Molecular Biology
- Dermatology
- Cell Biology