Corrigendum: Bullous pemphigoid IgG induces cell dysfunction and enhances the motility of epidermal keratinocytes via Rac1/proteasome activation.

[This corrects the article DOI: 10.3389/fimmu.2019.00200.].

Novel pathogenesis of atopic dermatitis from the view of cytokines in mice and humans.

Type 2 immunity and inflammation underlie allergic skin disorders, such as atopic dermatitis (AD). In type 2 inflammation, IL-4, IL-13, and IL-5, which are signature type 2 cytokines, are mainly produced by type 2 helper T (Th2) cells and form the characteristic features of AD. Epithelial cell-derived cytokines such as IL-25, IL-33, and TSLP initiate type 2 inflammation by modulating various cells, including group 2 innate lymphoid cells. Moreover, IL-31, a newly identified type 2 cytokine produced mainly by Th2 cells, induces pruritus by acting on sensory neurons in the skin. Based on both basic and clinical findings, several biologics targeting Th2 cytokines have been developed and exhibited significant efficacy as therapeutic reagents for AD. We have summarized the roles of each cytokine (IL-4, 5, 13, 25, 31, and 33, and TSLP) in the development of type 2 inflammation, especially AD, from the view of basic studies in mice and clinical trials/observation in humans.

Bullous Pemphigoid IgG Induces Cell Dysfunction and Enhances the Motility of Epidermal Keratinocytes via Rac1/Proteasome Activation.

Bullous pemphigoid (BP) is an autoimmune disease characterized by the formation of blisters, in which autoantibodies mainly target type XVII collagen (ColXVII) expressed in basal keratinocytes. BP IgG is known to induce the internalization of ColXVII from the plasma membrane of keratinocytes through macropinocytosis. However, the cellular dynamics following ColXVII internalization have not been completely elucidated. BP IgG exerts a precise effect on cultured keratinocytes, and the morphological/functional changes in BP IgG-stimulated cells lead to the subepidermal blistering associated with BP pathogenesis. Based on the electron microscopy examination, BP IgG-stimulated cells exhibit alterations in the cell membrane structure and the accumulation of intracellular vesicles. These morphological changes in the BP IgG-stimulated cells are accompanied by dysfunctional mitochondria, increased production of reactive oxygen species, increased motility, and detachment. BP IgG triggers the cascade leading to metabolic impairments and stimulates cell migration in the treated keratinocytes. These cellular alterations are reversed by pharmacological inhibitors of Rac1 or the proteasome pathway, suggesting that Rac1 and proteasome activation are involved in the effects of BP IgG on cultured keratinocytes. Our study highlights the role of keratinocyte kinetics in the direct functions of IgG in patients with BP.

Antifungal activity and mechanism of action of Ou-gon (Scutellaria root extract) components against pathogenic fungi.

Ou-gon, an extract from Scutellaria baicalensis Georgi root, has been shown to exhibit pronounced antifungal activity. The present study aimed to identify antifungal components of Ou-gon and to determine their mechanism of action against pathogenic fungi. Antifungal activity was assessed by the microbroth dilution method using four common human pathogenic fungi, Trichophyton rubrum, Trichophyton mentagrophytes, Aspergillus fumigatus, and Candida albicans. Components of crude Ou-gon extract were separated by reversed-phase high-performance liquid chromatography. Active antifungal components were identified by liquid chromatography-electrospray ionization tandem mass spectrometry. Terminal deoxynucleotidyl transferase dUTP nick end-labelling assay, SYTOX® green uptake assay, determination of intracellular reactive oxygen species and mitochondrial membrane potential as well as microscopy (confocal laser microscopy, scanning and transmission electron microscopy) were used to probe the mode of action. Two components with potent antifungal activity, baicalein and wogonin, were identified in Ou-gon. Baicalein showed potent antifungal activity against the four fungi tested. Wogonin displayed antifungal activity against all four fungi except C. albicans. The components are considered to induce apoptosis-like programmed cell death via hyperproduction of reactive oxygen species. This study enhances our understanding of the antifungal activity of Kampo medicine, and may contribute to the development of new and safe antifungal therapeutics.

Case of bullous pemphigoid coexisting with anti-desmoglein autoantibodies.

A 79-year-old Japanese woman had clinical and histopathological features of bullous pemphigoid, while direct immunofluorescence test revealed C3 and immunoglobulin G depositions in the lower cell surfaces of the epidermis in addition to those in the dermoepidermal junction. Chemiluminescent enzyme immunoassays were positive for desmoglein-1 and -3 antibodies in addition to anti-BP180 antibodies. In an immunoblotting study, antibodies against both 180-kDa bullous pemphigoid antigen and 130-kDa pemphigus vulgaris antigen were detected. Based on these results, bullous pemphigoid coexisting with anti-desmoglein autoantibodies was diagnosed in this case.

Toxic epidermal necrolysis induced by methazolamide in a Chinese-Korean man carrying HLA-B*59:01.

BACKGROUND: Methazolamide is used to lower intraocular pressure in patients with glaucoma. Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) associated with methazolamide treatment have been diagnosed in Korean, Japanese, and Japanese-American patients. According to recent research, the human leukocyte antigen (HLA) allele HLA-B*59:01 is strongly linked to SJS/TEN associated with methazolamide treatment. OBJECTIVE: A patient of Chinese-Korean ethnicity was diagnosed with TEN associated with methazolamide treatment. The purpose of this study was to examine the potential genetic basis of this disease. METHODS: A polymerase chain reaction sequence-specific primer (PCR-SSP) typing system was used to genotype this patient's peripheral blood DNA for HLA-B*59. RESULTS: The genotype HLA-B*59:01 was detected in the patient. CONCLUSIONS: This study demonstrates the genotype of HLA-B*59:01 in a patient with TEN associated with methazolamide treatment and thus supports the possible correlation between genetic background and methazolamide-associated SJS/TEN.

[Establishment of enzyme-linked immunosorbent assay in the detection of BP180NC16A-specific IgE and its significance in bullous pemphigoid].

OBJECTIVE: To establish a method of detecting circulating immunoglobulin E (IgE) autoantibodies for BP180NC16A and evaluate its significance in bullous pemphigoid (BP). METHODS: GST-NC16A fusion proteins were expressed in Escherichia coli using the pGEX-2T expression system and purified by glutathione affinity chromatography.For optimal working conditions of enzyme-linked immunoabsorbent assay (ELISA), checkerboard titrations were performed with serial dilutions of antigen. Also optimized dilution of secondary antibody was confirmed. Sera samples from 56 patients with BP, 24 healthy controls, 18 with pemphigus and 1 with Stevens-Johnson syndrome at our hospital during February 2011 to October 2012 were examined by the modified ELISA approach. The optimal cut-off point for a positive result was selected with receiver operating characteristic analysis. RESULTS: The optimized ELISA was performed with plates coated with 500 µg/ml GST-NC16A. And the optimal dilutions of sera samples and secondary antibody were 1: 10 and 1: 1000 respectively. According to the established cut-off value (0.549), 40 of 56 BP patients and none of controls had detectable levels of BP180NC16A IgE. CONCLUSION: The established ELISA provides a highly specific tool for the detection of IgE anti-BP180NC16A in BP patients.