Human epidermal Langerhans cells express the high affinity receptor for immunoglobulin E (Fc epsilon RI).

Abstract

SummaryIt has been suggested that epidermal Langerhans cells (LC) bearing immunoglobulin E (IgE) may be involved in the genesis of atopic disease. The identity of the IgE receptor(s) on LC remained unclear, although it represents a crucial point in understanding cellular events linked to the binding of allergens to LC via IgE. In this report, we demonstrate that epidermal LC express the high affinity receptor for the Fc fragment of IgE (FceRI) which has, so far, only been described on mast cells and basophils. Epidermal LC react with antibodies specific for the u subunit of the tetrameric (oL,~,23') FceRI. Specific transcripts for Fc~RIo~ and FceRI3~ were detected in LC and correspond to those of human basophils and of the human basophil cell line KU812. Furthermore, human basophils, KU812 cells, and LC express the putative B subunit. Thus human LC express the complete structure of FceRI. This finding opens new perspectives in the putative functional role of this structure on antigen-presenting cells.T he demonstration of IgE molecules on epidermal Langerhans cells (LC) 1 in patients with atopic dermatitis has implied that these cells should perform a major function in the pathophysiology of atopic disease (1, 2). Although initially, only receptors for the Fc fragment of IgG were identified on epidermal LC (3, 4), the low affinity receptor for IgE FceRII/CD23 (5) and the human IgE binding protein (eBP) (6) have now also been found on these cells in lesional, as well as in normal skin. However, attempts to completely block IgE binding on LC by a variety of anti-FceRII/CD23, antieBP, and/or anti-Fc3,R reagents remained unsuccessful, suggesting the presence of a third IgE-binding structure actually responsible for a part of the IgE-binding capacity of LC. We report here, that normal human LC also express the high a~nity receptor for IgE, Fcelkl, demonstrating that the presence of this structure is not restricted to mast cells and basophils. Our results also document the presence of the putative/~ chain on both human basophils and LC.

FHL3 negatively regulates human high-affinity IgE receptor β-chain gene expression by acting as a transcriptional co-repressor of MZF-1

“…FcεRI is expressed in limited types of cells such as mast cells, basophils, eosinophils [1], monocytes [2], Langerhans cells [3,4], platelets [5,6] and neutrophils [7]. Cross-linking of FcεRI on effector cells by antigen (allergen)-IgE complexes induces not only the release of chemical mediators in the early-phase reaction but also cytokine gene expressions, leading to the late-phase reaction.…”

The role of antigen presenting cells at distinct anatomic sites: they accelerate and they slow down allergies

“…monocytes of the peripheral blood into the inflammatory skin lesions (7)(8)(9)(10)(11)(12). A hallmark of both, epidermal LC and IDEC in the skin lesions of AD patients is the elevated expression of the high affinity receptor for immunoglobulin (IgE) (FceRI) ( Table 1) (13)(14)(15)(16)(17). Evidence suggests that allergens, which penetrate the epidermis due to the reduced skin barrier of AD patients, are taken up by FceRI-bound IgE molecules of epidermal DC, are internalized and processed in major histocompatibility class (MHC) II containing compartments within these cells (Fig.…”

“…1). This mechanism is referred to as antigen focusing and leads to a more efficient antigen presentation toward T-cells (12)(13)(14)(15)(16)(17)(18). Furthermore, mRNA for IL-16, the natural soluble ligand of the CD4 molecule that induces chemotactic response of CD4 + cells, monocytes and eosinophils is enhanced in active AD (18,19).…”

Expression of a Functional FcεRI on Rat Eosinophils and Macrophages

“…Receptor-bearing mast cells and basophils are able to release, upon engagement with IgE and multivalent Ag, inflammatory mediators (histamine, leukotrienes) as well as proinflammatory and immunoregulatory cytokines (1). Besides its expression on mast cells and basophils as an ␣␤␥ 2 tetramer, Fc⑀RI is also expressed on human Langerhans cells (2,3), monocytes (4), eosinophils (5), and platelets (6). This extended cellular distribution allows IgE and Fc⑀RI to be involved in allergen presentation (7) as well as in in vitro cytotoxicity reactions (Ab-dependent cellular cytotoxicity; ADCC) 2 toward parasite targets such as larvae from the trematode parasite Schistosoma mansoni (5,6).…”