Tissue Destruction in Bullous Pemphigoid Can Be Complement Independent and May Be Mitigated by C5aR2.

Bullous pemphigoid (BP), the most frequent autoimmune bullous disorder, is a paradigmatic autoantibody-mediated disease associated with autoantibodies against BP180 (type XVII collagen, Col17). Several animal models have been developed that reflect important clinical and immunological features of human BP. Complement activation has been described as a prerequisite for blister formation, however, the recent finding that skin lesions can be induced by anti-Col17 F(ab') fragments indicates complement-independent mechanisms to contribute to blister formation in BP.

Whole-Genome Expression Profiling in Skin Reveals SYK As a Key Regulator of Inflammation in Experimental Epidermolysis Bullosa Acquisita.

Because of the morbidity and limited therapeutic options of autoimmune diseases, there is a high, and thus far, unmet medical need for development of novel treatments. Pemphigoid diseases, such as epidermolysis bullosa acquisita (EBA), are prototypical autoimmune diseases that are caused by autoantibodies targeting structural proteins of the skin, leading to inflammation, mediated by myeloid cells. To identify novel treatment targets, we performed cutaneous genome-wide mRNA expression profiling in 190 outbred mice after EBA induction.

Regulatory T Cells Suppress Inflammation and Blistering in Pemphigoid Diseases.

Regulatory T cells (Tregs) are well known for their modulatory functions in adaptive immunity. Through regulation of T cell functions, Tregs have also been demonstrated to indirectly curb myeloid cell-driven inflammation. However, direct effects of Tregs on myeloid cell functions are insufficiently characterized, especially in the context of myeloid cell-mediated diseases, such as pemphigoid diseases (PDs).

Experimental Laminin 332 Mucous Membrane Pemphigoid Critically Involves C5aR1 and Reflects Clinical and Immunopathological Characteristics of the Human Disease.

Mucous membrane pemphigoid is an autoantibody-mediated disease predominantly affecting the oral cavity, pharynx, and conjunctiva. Conjunctival lesions may lead to impaired vision and, finally, blindness. About 25% of mucous membrane pemphigoid patients generate autoantibodies against the α3 chain of laminin 332 (LAMα3), a structural protein of epidermal/epithelial basement membranes.

The Leukotriene B and its Receptor BLT1 Act as Critical Drivers of Neutrophil Recruitment in Murine Bullous Pemphigoid-Like Epidermolysis Bullosa Acquisita.

Recruitment of neutrophils and eosinophils into the skin is a hallmark of pemphigoid diseases. The molecular cues regulating granulocyte recruitment into the skin and the individual contributions of neutrophils and eosinophils to pemphigoid diseases are, however, poorly understood. The lipid mediator leukotriene B (LTB) is a potent granulocyte chemoattractant and is abundant in the skin blister fluid of bullous pemphigoid (BP) patients, but its pathogenic significance is unknown.

Reduced skin blistering in experimental epidermolysis bullosa acquisita after anti-TNF treatment.

Epidermolysis bullosa acquisita (EBA) is a difficult-to-treat subepidermal autoimmune blistering skin disease (AIBD) with circulating and tissue-bound anti-type VII collagen antibodies. Different reports have indicated an increased concentration of tumor necrosis factor alpha (TNF) in the serum and blister fluid of patients with subepidermal AIBDs. Furthermore, successful anti-TNF treatment has been reported for individual patients with AIBDs.

Correlation of Serum Levels of IgE Autoantibodies Against BP180 With Bullous Pemphigoid Disease Activity.

Importance: Bullous pemphigoid (BP) is by far the most frequent autoimmune blistering disease. The presence of IgE autoantibodies against the transmembrane protein BP antigen 2 (BP180, type XVII collagen) has previously been reported in 22% to 100% of BP serum samples, and the pathogenic relevance of anti-BP180 IgE has been suggested in various experimental models and by the successful use of omalizumab in individual patients with BP.

Objectives: To determine the rate of anti-BP180-reactive IgE in BP, to evaluate the diagnostic relevance of anti-BP180 IgE in BP, and to correlate anti-BP180 IgE with disease activity and the clinical phenotype of patients with BP.

IgE-mediated mechanisms in bullous pemphigoid and other autoimmune bullous diseases.

Autoimmune bullous diseases (AIBDs) are characterized by autoantibodies against structural proteins of the dermal-epidermal junction (in pemphigoid diseases) and the epidermal/ epithelial desmosomes (in pemphigus diseases). By far, the most common AIBD is bullous pemphigoid, which is immunopathologically characterized by autoantibodies against BP180 (type XVII collagen) and BP230. IgG and, to a lesser extent, IgA autoantibodies are the major autoantibody isotypes in these disorders.

Fcγ receptors III and IV mediate tissue destruction in a novel adult mouse model of bullous pemphigoid.

Bullous pemphigoid (BP) and epidermolysis bullosa acquisita are subepidermal autoimmune blistering diseases mediated by autoantibodies against type XVII collagen (Col17) and Col7, respectively. For blister formation, Fc-mediated events, such as infiltration of inflammatory cells in the skin, complement activation, and release of proteases at the dermal-epidermal junction, are essential. Although in the neonatal passive transfer mouse model of BP, tissue destruction is mediated by Fcγ receptors (FcγRs) I and III, the passive transfer model of epidermolysis bullosa acquisita completely depends on FcγRIV.

GM-CSF modulates autoantibody production and skin blistering in experimental epidermolysis bullosa acquisita.

GM-CSF activates hematopoietic cells and recruits neutrophils and macrophages to sites of inflammation. Inhibition of GM-CSF attenuates disease activity in models of chronic inflammatory disease. Effects of GM-CSF blockade were linked to modulation of the effector phase, whereas effects on early pathogenic events, for example, Ab production, have not been identified.

Concomitant bullous pemphigoid and dermatitis herpetiformis.

Dermatitis herpetiformis and bullous pemphigoid are bullous autoimmune diseases of the skin microscopically characterized by subepidermal blisters. We present a 77-year-old patient with an 18-month history of disseminated pruritic papular lesions. Direct immunofluorescence microscopy revealed linear deposition of IgG at the basement membrane zone as well as granular deposits of IgA in the papillary dermis.