Granzyme B inhibition reduces autoantibody-induced dermal-epidermal separation in an ex vivo model of epidermolysis bullosa acquisita.

The pemphigoid disease epidermolysis bullosa acquisita (EBA) is an autoimmune blistering skin disease characterized by autoantibodies against type VII collagen (COL7), immune cell infiltrates at the dermal-epidermal junction and subepidermal blistering. Proteases, particularly granzyme B (GzmB), have been established as therapeutic targets for the treatment of EBA and other pemphigoid diseases. We investigated the impact of the novel GzmB inhibitor SNT-6935 on anti-COL7 IgG-induced subepidermal blistering in a well-established EBA ex vivo model. Our findings demonstrate that pharmacological targeting of GzmB with its selective inhibitor SNT-6935 significantly reduced autoantibody-induced dermal-epidermal separation in human skin cryosections. Interestingly, treatment of skin cryosections with recombinant human GzmB alone did not cause dermal-epidermal separation, suggesting that additional mechanisms alongside GzmB are required for tissue damage in EBA. In conclusion, our study highlights the significant contribution of GzmB to the pathogenesis of EBA and supports the notion of GzmB as a therapeutic target in EBA and other pemphigoid diseases.

Role of eosinophils in the pathogenesis of bullous pemphigoid / 中华皮肤科杂志

Bullous pemphigoid (BP) is the most common autoimmune subepidermal blistering skin disease,and a large number of eosinophils (EOS) obviously infiltrate the dermis of BP lesions.Additionally,EOS and their activated cytokines and chemokines are abundantly present in blisters and peripheral blood of BP patients.It is also proved that EOS can induce the dermal-epidermal separation.The level of interleukin (IL)-5 is markedly increased in the sera and blister fluids of BP patients,and IL-5 secreted by Th2 cells and EOS can regulate the differentiation,activation and survival of EOS.All the above evidence indicates that EOS are associated with the occurrence of BP.Researches on EOS and their cytokines will develop a new field of targeted therapy for BP.

Picosecond 532-nm neodymium-doped yttrium aluminum garnet laser-a promising modality for the management of verrucous epidermal nevi.

The verrucous epidermal nevus (VEN) is the most common type of epidermal nevi. As lesions can be disfiguring, treatment is often sought. Many therapeutic approaches have been reported, with variable efficacy and safety. Picosecond (PS) lasers are novel laser devices designated to target small chromophores. A side effect of these lasers is blistering due to epidermal-dermal separation. We aimed to harness this side effect of the PS lasers to treat patients with VEN. The purpose of this study was to report our experience treating VEN using a PS 532-nm laser. We present a retrospective case series of six patients with large VEN who were treated using a PS 532-nm laser (2-6 treatments, 8-10 weeks apart). Response in clinical photographs was assessed by two independent dermatologists and graded on a scale of 0 (exacerbation) to 4 (76-100% improvement). Patient satisfaction was recorded on a scale of 1-5. All patients demonstrated significant improvement. Average improvement was 3.7 on the quartile scale of improvement. Patient satisfaction rate averaged 4.7. The PS 532-nm laser is a promising novel modality for the treatment of large VEN.

Eosinophils as putative therapeutic targets in bullous pemphigoid.

Bullous pemphigoid (BP) is the most common autoimmune subepidermal blistering skin disease and is characterized by the presence of autoantibodies directed against the hemidesmosomal proteins BP180 and BP230 that can be detected in the skin and serum of BP patients. Histologically, the dermal infiltration of eosinophils is obvious. The objective of this review was to present evidence that eosinophils play a key role in the pathogenesis of BP. Eosinophils, together with cytokines and chemokines regulating their production, recruitment and activation, are abundantly present in lesional skin, in blisters and in peripheral blood of patients with BP. Recently, using a cryosection model, eosinophils were demonstrated to induce dermal-epidermal separation in the presence of BP antibodies. Thus, eosinophils and their products, as well as mediators regulating their function, present promising targets for the treatment of BP.

A comparison between different existing methods used to separate epidermal cells from skin biopsies for autologous transplantation.

BACKGROUND: Burn surgeons use autologous skin graft technique for patients, but a challenge remains for large surface wounds. Recently, a method was described which used a small piece of skin to cover a 70 times greater surface by spraying epidermal cells on injured skin. We designed a comparative study to find the best method to make an epidermal cell suspension. MATERIALS AND METHODS: Eleven discarded skin samples were sent to our laboratory from Ghotboddin Burn Hospital, Shiraz. Each sample was sliced into four small pieces (1 cm(2)) and each piece was treated with a different chemical including sodium bromide (2N) and (4N), ammonium hydroxide (2N), and trypsin (0.05%) for 20 minutes. The epidermis and dermis were separated using forceps. Trypsin was added to all samples (except the trypsinized sample) to begin the intercellular detachment. Afterward, epidermis was sliced into small pieces followed by filtration and centrifugation. Cells were counted using hemocytometer. Identification of keratinocytes and melanocytes was made through immunocytochemical staining for cytokeratin and melanosome antigens, respectively. RESULTS: There was a significant difference in alive cell counts comparing cells obtained from NaBr (4N) method to other methods. Considering total cell count and alive cell count, NaBr (4N) yielded the most cells. Immunocytochemical staining showed that in all methods, some cells are stained positively for cytokeratin antibody and some for melanosome antibody. CONCLUSION: Although recent papers had advised trypsin method to make a cell suspension to use for burn patients, we found that NaBr (4N) method yields more alive cells and less toxicity.

Preservation of antigenicity of autoimmune blistering diseases according to different methods of dermo-epidermal separation / 대한피부과학회지

There are many known methods of dermo-epidermal separation for the investigation of autoimmune blistering diseases. Investigators should select a proper method since many differences exist preservation of antigenicity. In order to determine the stabilization of antigenirity by different separation methods, we have separated dermo-epidermal junction by means of 1M s;ilt, 56C PBS, 20mM EDTA and dispase. Indirect immunofluarescence and immunoblotting were performed on each specimen with sera of patients with pemphigus vulgaris, pemphigus foliaceus, paraneoplastic pemphigus, bullous pemphigoid and epidermolysis bullosa acquisita. The results are as follows : 1. In indirect immunofluorescence study of pemphigus group, best, result were obtained when normal skin without dermo-epidermal separation was used. Dispase well preserved antigenicity of pemphigus after dermo-epidermal separation, but no differences were noted in antigenicity stabilization among separation mehods by immunoblotting. 2. In indirect immunofluorecence study for differentiation of bullous pemphigoid and epidermolysis bullosa acquisita, we recommend EDTA and dispase methods in addition to 1M salt induced skin separation that have been most popularly used. 3. Results of the immunoblotting of bullous pemphigoid showed that 1M salt, EDTA and heat preserved the antigenicity well but the antigenicity was lost by dispase. 4. Results of the immunoblotting of epidermolysis bullosa acquisita she wed that antigen did not exist in epidermal extract. 5. Antigen preservation according to the different methods of demo-epidermal separation was not identical between indirect immunofluorescence and immunoblotting.