Search

Narifumi Akaza,1 Kazuto Takasaki,2 Eri Nishiyama,2 Atsuko Usui,2 Shiori Miura,1 Aya Yokoi,3,4 Kyoko Futamura,4 Kayoko Suzuki,4 Youichi Yashiro,1 Akiko Yagami4 1Research Laboratories, Nippon Menard Cosmetic Co., Ltd., Nagoya, Japan; 2Fasmac Co., Ltd., Kanagawa, Japan; 3Nihombashi Irodori Dermatology Clinic, Tokyo, Japan; 4Department of Allergology, Fujita Health University School of Medicine, Nagoya, JapanCorrespondence: Narifumi Akaza, Research Laboratories, Nippon Menard Cosmetic Co., Ltd., 2-7 Torimi-cho, Nishi-ku, Nagoya, Aichi, 451-0071, Japan, Tel +81 52 531 6263, Fax +81 52 531 6277, Email akaza.narifumi@menard.co.jpBackground: Acne vulgaris (acne) and cutaneous resident microorganisms are considered to be closely related. However, the bacterial and fungal microbiota in the comedonal contents of inflammatory acne lesions have not yet been investigated in detail.Purpose: To clarify the relationship between cutaneous microorganisms and acne, we examined the microbiome in the comedonal contents of inflammatory acne and on the facial skin of patients with acne using 16s rRNA and ITS gene sequencing with a next-generation sequencer (NGS).Patients and Methods: Twenty-two untreated Japanese acne outpatients were examined. The comedonal contents of inflammatory acne lesions on the face were collected using a comedo extractor. Skin surface samples from facial skin were collected using the swab method.Results: The results obtained revealed that the predominant bacteria in the comedonal contents of inflammatory acne were Cutibacterium spp. (more prominent in areas with large amounts of sebum), while those on the skin surface were Staphylococcus spp. Malassezia spp., particularly Malassezia restricta, were the predominant fungi in both the comedonal contents of inflammatory acne and on the skin surface. The bacterial microbiome in comedonal contents exhibited stronger metabolic activity, including the production of enzymes related to acne, than that on the skin surface.Conclusion: These results indicate that acne is an inflammatory disease involving the overgrowth of Cutibacterium acnes and other cutaneous resident microorganisms, including Malassezia spp.Keywords: acne vulgaris, Cutibacterium, Staphylococcus, Malassezia, microbiome, microbiota, next generation sequencing

Immediate allergy caused by natto, a popular Japanese food prepared by fermenting soybeans with Bacillus subtilis var. natto, has been reported. Polygamma glutamic acid (PGA) in the sticky substance around natto beans has been reported to be a causative allergen of natto allergy. However, some of our patients with natto allergy were negative for PGA in the skin prick test (SPT). The sticky substance of natto beans contains a subtilisin family serine protease, nattokinase, along with PGA. In this study, we aimed to examine the antigenicity of nattokinase in natto allergy.Eight patients, who developed symptoms after ingesting natto and positively reacted to natto (seven to the sticky substance in natto and one to the whole natto product) in their SPT, were enrolled in this study. To analyze IgE reactivity, we performed immunoblotting, ELISA, and SPT for natto (bean and sticky substance), and/or PGA, and/or nattokinase and/or cultured B. subtilis var. natto extract.In the SPT, four cases each were PGA-positive and PGA-negative. Immunoblotting of the sera from PGA-negative patients showed a protein band at 30 kDa, which was identified as nattokinase. Three PGA-negative cases, but not three PGA-positive cases, showed a positive reaction to nattokinase in the SPT and had a history of atopic dermatitis. The ELISA for nattokinase revealed a positive reaction of PGA-negative cases and negative reaction of PGA-positive cases in the SPT.We identified a subtilisin family serine protease, nattokinase, as a novel allergen in natto allergy patients unsensitized to PGA.

The "itch-scratch cycle" is a clinically well-known cause of exacerbation of atopic dermatitis (AD), but the underlying molecular mechanisms remain largely unknown.To test our hypothesis that some molecules released from damaged epidermal keratinocytes by scratching inducetype 2 responses in intact skin dermal cells, leading to exacerbation of AD.Normal human dermal fibroblasts (NHDF) and human dermal blood microvascular endothelial cells (HMVEC-dBl) were treated with an epidermal keratinocyte homogenate (EKH). We used qPCR and ELISA, respectively, to measure the mRNA expressions and protein concentrations of various cytokines, including IL-6, IL-8, thymic stromal lymphopoietin (TSLP), and IL-33. We analyzed IL-33 protein expression in the nuclear fractions of NHDF by Western blotting. We also investigated the effects of IL-1R1 gene-silencing and several AD therapeutic drugs on EKH induction of cytokine production by the dermal cells.EKH significantly induced IL-6 and IL-8 in NHDF and HMVEC-dBl. EKH also induced type 2 cytokines, TSLP and IL-33, in NHDF. IL-1R1 gene-silencing in NHDF partially attenuated the induction. Dexamethasone (a corticosteroid) significantly inhibited, while ABT494 (a JAK1 inhibitor) partially inhibited, EKH's induction of cytokines in fibroblasts. In contrast, ABT494 was more effective than dexamethasone in inhibiting the cytokine induction in HMVEC-dBl.This study showed that a homogenate of epidermal keratinocytes significantly induced AD-related cytokines in cultured dermal cells, and IL-1α, an alarmin, might be involved in that induction. Combined use of corticosteroids and JAK1 inhibitors is likely to block the itch-scratch cycle by targeting different types of dermal cells.

Silica crystals (silica), which are the main mineral component of volcanic ash and desert dust, can activate the caspase-1-activating inflammasome in phagocytic cells to secrete IL-1β. Although inhalation of silica-containing dust is known to exacerbate chronic respiratory diseases, probably through inflammasome activation, its direct effects on bronchial epithelial cells remain unclear. Here, we show that silica and double-stranded RNA (dsRNA) synergistically induces caspase-9-dependent apoptosis, but not inflammasome activation, of bronchial epithelial cells. Intranasal administration of silica and dsRNA to mice synergistically enhanced neutrophil infiltration in the airway without IL-1β release in the bronchoalveolar lavage fluid. Histopathological analysis revealed that silica or dsRNA alone induced slight airway inflammation, whereas combined administration significantly enhanced airway inflammation and epithelial damage. These novel findings suggest that inhalation of silica-containing dust may cause inflammasome-independent airway inflammation, possibly by damaging the epithelial barrier, especially at the time of viral infection. These responses may also be involved in acute lung injury caused by inhaled silica-containing dust.

Background: Whileβ2-adrenoceptor agonists (β2-agonists) are widely used as bronchodilators in the treatment of asthma, there has been increasing concern that regular use of β2-agonists may adversely affect the control of asthma. However, the molecular mechanisms of such undesirable effects of β2-agonists are not fully understood. In this study, we examined the effects of β2-agonists on cytokine-induced production of thymic stromal lymphopoietin (TSLP), an indispensable cytokine in the development of allergic diseases, by lung tissue cells. Methods: Normal human bronchial epithelial cells (NHBE), smooth muscle cells (BSMC) and fibroblasts (NHLF) were stimulated with the IL-4 and TNF-α cytokines, alone and in combination, and their production of TSLP was examined by ELISA. The effects of β2-agonists (salmeterol, formoterol, salbutamol), intracellular cyclic adenosine monophosphate (cAMP)-elevating agents (8-bromo-cAMP, dibutyryl cAMP, forskolin) and a corticosteroid (fluticasone) on the cytokine-induced TSLP production were examined. Results: The following results were observed in all three types of lung tissue cells tested (that is, NHBE, BSMC and NHLF). Costimulation with IL-4 and TNF-α significantly induced TSLP production, and β2-agonists further enhanced it via upregulation of intracellular cAMP. However, addition of a corticosteroid to the cytokines and β2-agonist resulted in a marked decrease in TSLP production. Conclusions: β2-Agonists significantly enhanced the cytokine-induced TSLP production by primary human lung tissue cells. This may be partly responsible for the undesirable clinical effects of continuous β2-agonist monotherapy, and combination therapy with a corticosteroid might effectively inhibit TSLP-mediated allergic inflammation.

Background Although platelets play a key role in allergic inflammation in addition to their well-established role in hemostasis, the precise mechanisms of how platelets modulate allergic inflammation are not fully understood. IL-33 is an essential regulator of innate immune responses and allergic inflammation. Objective We sought to determine the expression of IL-33 protein by platelets and its functional significance in airway inflammation. Methods IL-33 protein in human platelets, the human megakaryocyte cell line MEG-01, and bone marrow–derived mouse megakaryocytes was detected by using Western blot analysis and fluorescent immunostaining. We examined the functional relevance of IL-33 protein in platelets by comparing platelet-intact and platelet-depleted groups in a murine model of IL-33–dependent airway eosinophilia elicited by intranasal administration of papain. We further compared the additive effect of administration of platelets derived from wild-type versus IL-33–deficient mice on the papain-induced eosinophilia. Results Platelets and their progenitor cells, megakaryocytes, constitutively expressed IL-33 protein (31 kDa). Papain-induced IL-33–dependent airway eosinophilia in mice was significantly attenuated by platelet depletion. Conversely, concomitant administration of platelets derived from wild-type mice but not IL-33–deficient mice enhanced the papain-induced airway eosinophilia. Conclusions Our novel findings suggest that platelets might be important cellular sources of IL-33 protein in vivo and that platelet-derived IL-33 might play a role in airway inflammation. Therefore platelets might become an attractive novel therapeutic target for asthma and probably allergic inflammation.

Overproduction of periostin, an IL-13-inducible matricellular protein, despite corticosteroid treatment is thought to be involved in the chronicity of allergic inflammation seen in corticosteroid-refractory tissue fibrosis. Therefore, we hypothesized that some tissue cells must produce periostin in a corticosteroid-insensitive manner. Here, we show that IL-4 and IL-13 each induced comparable levels of periostin production by primary normal human fibroblasts and microvascular endothelial cells derived from lung and skin. Dexamethasone, a corticosteroid, completely inhibited IL-4/13-induced, but did not affect TGF-β-induced, periostin production by fibroblasts. In contrast, dexamethasone synergistically enhanced IL-4/13-induced periostin production by microvascular endothelial cells. TGF-β did not induce periostin production by microvascular endothelial cells. Our novel findings suggest that IL-4/13-induced microvascular endothelium-derived and/or TGF-β-induced fibroblast-derived periostin might play a pivotal role in corticosteroid-refractory tissue fibrosis, leading to chronic allergic inflammation in the lung and/or skin.

Lens epithelium-derived growth factor (LEDGF)/dense fine speckles 70 kDa protein (DFS70) is a transcription cofactor that enhances growth and is overexpressed in various cancers. In the epidermis, LEDGF/DFS70 localizes to the nucleus of keratinocytes (KCs) in the basal layers and to the cytoplasm of cells in the upper layers. However, the biological and pathological relevance of LEDGF/DFS70 in the epidermis is virtually unknown. Compared with normal epidermis, we detected strong nuclear staining of LEDGF/DFS70 in both the spinous and basal layers of the epidermis of psoriatic skin. To investigate the roles of LEDGF/DFS70 in the epidermis of psoriatic skin, we generated HaCaT cells that constitutively express enhanced green fluorescence protein (EGFP)-LEDGF (EGFP-LEDGF-HaCaT) or EGFP alone (EGFP-HaCaT) as a control. EGFP-LEDGF-HaCaT cells had increased expression of IL-6, which was attenuated by LEDGF-specific RNA interference and the p38-specific inhibitors SB-239063 and SB-203580. Furthermore, EGFP-LEDGF-HaCaT cells had increased expression of S100A7 and S100A9 and decreased expression of filaggrin. These findings are compatible with the expression pattern in psoriatic tissues. Taken together, these results strongly suggest that ectopic expression of LEDGF/DFS70 in KCs could be involved in the pathology of psoriasis vulgaris.

Whilebeta(2)-adrenoceptor agonists (beta(2)-agonists) are widely used as bronchodilators in the treatment of asthma, there has been increasing concern that regular use of beta(2)-agonists may adversely affect the control of asthma. However, the molecular mechanisms of such undesirable effects of beta(2)-agonists are not fully understood. In this study, we examined the effects of beta(2)-agonists on cytokine-induced production of thymic stromal lymphopoietin (TSLP), an indispensable cytokine in the development of allergic diseases, by lung tissue cells.Normal human bronchial epithelial cells (NHBE), smooth muscle cells (BSMC) and fibroblasts (NHLF) were stimulated with the IL-4 and TNF-alpha cytokines, alone and in combination, and their production of TSLP was examined by ELISA. The effects of beta(2)-agonists (salmeterol, formoterol, salbutamol), intracellular cyclic adenosine monophosphate (cAMP)-elevating agents (8-bromo-cAMP, dibutyryl cAMP, forskolin) and a corticosteroid (fluticasone) on the cytokine-induced TSLP production were examined.The following results were observed in all three types of lung tissue cells tested (that is, NHBE, BSMC and NHLF). Costimulation with IL-4 and TNF-alpha significantly induced TSLP production, and beta(2)-agonists further enhanced it via upregulation of intracellular cAMP. However, addition of a corticosteroid to the cytokines and beta(2)-agonist resulted in a marked decrease in TSLP production.beta(2)-Agonists significantly enhanced the cytokine-induced TSLP production by primary human lung tissue cells. This may be partly responsible for the undesirable clinical effects of continuous beta(2)-agonist monotherapy, and combination therapy with a corticosteroid might effectively inhibit TSLP-mediated allergic inflammation.

The unfolded protein response (UPR), which is induced by stress to the endoplasmic reticulum (ER), is involved in the functional alteration of certain cells, such as the differentiation of B cells to plasma cells. The aim of this study is to determine whether the UPR is activated during epidermal keratinocyte (KC) differentiation. Here, we show that the expression of the UPR-induced proteins Bip/GRP78 and HRD1 was increased in cells in the supra-basal layers of normal human epidermis that contain KCs undergoing differentiation as well as in skin-equivalent cultured KCs. However, Bip/GRP78 and HRD1 were poorly expressed in proliferating KCs in squamous cell carcinoma and psoriasis vulgaris tissues. The epidermal growth factor receptor tyrosine kinase inhibitor, PD153035, which induces KC differentiation, upregulated UPR-induced marker mRNAs and proteins. Furthermore, microarray analyses and quantitative PCR revealed that ER stress-inducing reagents, tunicamycin (TU), thapsigargin, and brefeldin A, altered the expression of genes essential for human epidermal KC differentiation, including C/EBPbeta, KLF4, and ABCA12 in vitro. However, ABCA12 and KLF4 mRNA did not increase with TU treatment after siRNA-mediated knockdown of XBP-1. Taken together, our findings strongly suggest that the UPR is activated during normal epidermal KC differentiation and induces C/EBPbeta, KLF4, and ABCA12 mRNAs.

Background: Physiological and pathological skin eruptions are commonly encountered in neonates in our clinical practice. However, the types of skin eruptions that are associated with the subsequent development of atopic dermatitis and the mechanisms of these associations remain uncertain. Methods: A total of 105 newborn babies with normal delivery were enrolled in this prospective cohort study. The cord blood eosinophil count was measured and the neonates were examined at 1 month of age and followed until 8 years of age. Results: At 1 month of age, infantile eczema, seborrheic dermatitis, intertrigo and diaper dermatitis were diagnosed in a total of 29, 7, 14 and 24 neonates, respectively. No association was found among the prevalences of these eruptions. Neonates with infantile eczema had a significantly higher number and ratio of eosinophils in the cord blood (eosinophil count: 670.8 ± 67.8 vs. 349.0 ± 30.3/µl, p < 0.0001; eosinophil ratio: 5.12 ± 0.53 vs. 2.61 ± 0.22%, p < 0.0001, for the presence and the absence of infantile eczema, respectively). In contrast, no such tendency was found for any other skin eruptions. In neonates with infantile eczema at 1 month of age, the diagnosis of atopic dermatitis had been made significantly earlier and the prevalence of wheezing illness was significantly higher than in those without infantile eczema until 2 years of age. Conclusion: Infantile eczema, but not other skin eruptions, precedes the development of atopic dermatitis and wheezing illness during early infancy, presumably because of the activation of eosinophils before birth.