Blockade of HMGB1 Reduces Inflammation and Pruritus in Atopic Dermatitis by Inhibiting Skin Fibroblasts Activation.

INTRODUCTION: Atopic dermatitis (AD) is a chronic inflammatory skin disease characterized by relapsed eczema and serious pruritus. High-mobility group box 1 protein (HMGB1) is a nuclear-binding protein and serves as an alarmin to promote inflammatory responses. METHODS: In this study, we established an AD mouse model by topical use of MC903 on ears and then used a specific HMGB1-binding peptide cIY8 and a HMGB1 inhibitor of glycyrrhizin to investigate HMGB1 on fibroblast activation in the pathogenesis of AD-like symptoms. RESULTS: Topical use of cIY8 and oral use of glycyrrhizin significantly improved the MC903-induced AD-like symptoms and pathological changes of the ears and scratching behavior in an AD mouse model; cIY8 treatment inhibited the higher mRNAs of IL-1α, IL-4, IL-5, IL-13, and IL-31 in the ears. In human fibroblasts, HMGB1 caused nuclear translocation of NF-kB, and the nuclear translocation could be inhibited by pre-treatment of HMGB1 with cIY8, suggesting that NF-κB signaling pathway participates in the HMGB1-induced inflammation of AD in fibroblasts and that cIY8 effectively impedes the function of HMGB1. Glycyrrhizin inhibited the Ca2+ signaling induced by ionomycin in mouse primary fibroblasts. The fibroblast-related proteins of α-SMA, Hsp47, and vimentin and the pruritus-related proteins of IL-33 and periostin were increased in the ears of the AD mouse model, the ratio of EdU incorporation became higher in mouse fibroblasts treated with MC903, and the higher proliferation and inflammatory responses of the fibroblasts could be reversed by glycyrrhizin treatment. CONCLUSIONS: Fibroblast activation by HMGB1 is one of the critical processes in the development of inflammation and pruritus in the AD mouse model. The specific HMGB1-binding peptide cIY8 and the HMGB1 inhibitor glycyrrhizin inactivate skin fibroblasts to alleviate the inflammation and pruritus in the AD mouse model. Peptide cIY8 may be topically used to treat AD patients in the future.

Comparison of Efficacy of Baricitinib and Dupilumab in the Treatment of Chinese Moderate-To-Severe Atopic Dermatitis: A Retrospective Study.

INTRODUCTION: The treatment of atopic dermatitis (AD) patients with insufficient response or intolerance to topical medication remains clinical challenges, and there is a paucity of head-to-head trials comparing the efficacy of novel biological agents such as JAK inhibitor and antibody. METHODS: To compare the efficacy of selective JAK1/JAK2 inhibitor baricitinib and interleukin-4 monoclonal antibody dupilumab in the treatment of patients with moderate-to-severe AD, a retrospective cohort study method was adopted. Clinical data from June 2020 to April 2022 were systematically reviewed. Eligible patients who received baricitinib or dupilumab were screened according to the following inclusion criteria: (1) age ≥ 18 years; (2) moderate-to-severe AD: baseline investigator global assessment (IGA) score ≥ 3, baseline eczema area and severity index (EASI) score ≥ 16; (3) poor response or intolerance to at least one topical drug in the past 6 months; (4) no topical glucocorticoids were used in the past 2 weeks and no systematic treatment was given in the past 4 weeks. Patients of the baricitinib group were treated with oral baricitinib in doses of 2 mg per day for 16 weeks, and patients of the dupilumab group were treated with standardized use of dupilumab for 16 weeks, with the initial 600 mg subcutaneous injection and the following 300 mg subcutaneous injection every 2 weeks. The clinical efficacy score indexes including the IGA score, EASI score, and Itch Numeric Rating Scale (NRS) score. These scores at 0, 2, 4, 8, 12, and 16 weeks after the start of treatment were collected. RESULTS: A total of 54/45 patients treated with baricitinib/dupilumab were included. There was no significant difference in the decrease of all scores between the two groups at the 4th week (p > 0.05). There was no difference in the EASI score and Itch NRS score (p > 0.05), but the IGA score of the baricitinib group was lower at the 16th week (Z = 4.284, p < 0.001). Within the first 4 weeks, the Itch NRS score of the baricitinib group decreased rapidly, but with the prolongation of treatment time, there was no significant difference between the two groups at the 16th week (Z = 1.721, p = 0.085). CONCLUSIONS: The efficacy of baricitinib at a dose of 2 mg daily was similar to dupilumab, and the improvement in pruritus was significantly faster in the early stage of treatment (the first 4 weeks) than that of dupilumab.

Impact of Omalizumab on Anaphylaxis in Patients Treated for Chronic Urticaria.

BACKGROUND: Anaphylaxis is a life-threatening systemic allergic reaction. Omalizumab (OMA) is an established treatment in chronic urticaria (CU), but experience in anaphylaxis is limited. OBJECTIVES: The objective was to evaluate the efficacy and safety of OMA on anaphylaxis in patients with CU who are resistant to antihistamine therapy and have a history of anaphylaxis. METHOD: Patients with antihistamine-resistant CU and a history of anaphylaxis were eligible. OMA was given 300 mg/150 mg every 4 weeks. Urticaria control test (UCT) scores, the episodes of anaphylaxis, and adverse events were recorded during the OMA treatment. RESULTS: A total of 7 adults were included. After starting OMA, all of them achieved a complete control (UCT = 16) after 3 months of OMA treatment; 6 of them did not suffer any attack of anaphylaxis in the follow-up periods (5 patients for more than 12 months and 1 patient for 4 months). No adverse events were observed. CONCLUSION: The study indicated the efficacy and safety of OMA for antihistamine-resistant CU patients with a history of anaphylaxis and its potential as a prevention option for anaphylaxis.

Treatment patterns and outcomes in patients with chronic urticaria during pregnancy: Results of PREG-CU, a UCARE study.

BACKGROUND: Although chronic urticaria (CU) is a common and primarily affects females, there is little data on how pregnancy interacts with the disease. OBJECTIVE: To analyse the treatment use by CU patients before, during and after pregnancy as well as outcomes of pregnancy. METHODS: PREG-CU is an international, multicentre study of the Urticaria Centers of Reference and Excellence network. Data were collected via a 47-item-questionnaire completed by CU patients who became pregnant during their disease course. RESULTS: Questionnaires from 288 CU patients from 13 countries were analysed. During pregnancy, most patients (60%) used urticaria medication including standard-dose second generation H1-antihistamines (35.1%), first generation H1-antihistamines (7.6%), high-dose second-generation H1-antihistamines (5.6%) and omalizumab (5.6%). The preterm birth rate was 10.2%; rates were similar between patients who did and did not receive treatment during pregnancy (11.6% vs. 8.7%, respectively). Emergency referrals for CU and twin birth were risk factors for preterm birth. The caesarean delivery rate was 51.3%. More than 90% of new-borns were healthy at birth. There was no link between any patient or disease characteristics or treatments and medical problems at birth. CONCLUSION: Most CU patients used treatment during pregnancy especially second-generation antihistamines which seem to be safe during pregnancy regardless of the trimester. The rates of preterm births and medical problems of new-borns in CU patients were similar to population norms and not linked to treatment used during pregnancy. Emergency referrals for CU increased the risk of preterm birth and emphasize the importance of sufficient treatment to keep urticaria under control during pregnancy.

Risk factors for systemic reactions in typical cold urticaria: Results from the COLD-CE study.

BACKGROUND: Cold urticaria (ColdU), that is, the occurrence of wheals or angioedema in response to cold exposure, is classified into typical and atypical forms. The diagnosis of typical ColdU relies on whealing in response to local cold stimulation testing (CST). It can also manifest with cold-induced anaphylaxis (ColdA). We aimed to determine risk factors for ColdA in typical ColdU. METHODS: An international, cross-sectional study COLD-CE was carried out at 32 urticaria centers of reference and excellence (UCAREs). Detailed history was taken and CST with an ice cube and/or TempTest® performed. ColdA was defined as an acute cold-induced involvement of the skin and/or visible mucosal tissue and at least one of: cardiovascular manifestations, difficulty breathing, or gastrointestinal symptoms. RESULTS: Of 551 ColdU patients, 75% (n = 412) had a positive CST and ColdA occurred in 37% (n = 151) of the latter. Cold-induced generalized wheals, angioedema, acral swelling, oropharyngeal/laryngeal symptoms, and itch of earlobes were identified as signs/symptoms of severe disease. ColdA was most commonly provoked by complete cold water immersion and ColdA caused by cold air was more common in countries with a warmer climate. Ten percent (n = 40) of typical ColdU patients had a concomitant chronic spontaneous urticaria (CSU). They had a lower frequency of ColdA than those without CSU (4% vs. 39%, p = .003). We identified the following risk factors for cardiovascular manifestations: previous systemic reaction to a Hymenoptera sting, angioedema, oropharyngeal/laryngeal symptoms, and itchy earlobes. CONCLUSION: ColdA is common in typical ColdU. High-risk patients require education about their condition and how to use an adrenaline autoinjector.

Adrenaline autoinjector is under-prescribed in typical cold urticaria patients living in tropical climate countries.

Background: The diagnosis of typical cold urticaria (ColdU) relies on whealing in response to local cold stimulation testing (CST). It can also manifest with cold-induced anaphylaxis (ColdA). Till date, it is largely unclear how often patients with ColdU receive adrenaline treatment and are provided with an adrenaline autoinjector (AAI). Methods: An international, cross-sectional study, COLD-CE (i.e., comprehensive evaluation of ColdU and other cold-induced reactions), was carried out at 32 UCAREs. Detailed histories were taken and CST with an ice cube and/or TempTest® performed. ColdA was defined as an acute cold-induced (i.e., by cold water, air, or surfaces) involvement of the skin and/or visible mucosal tissue and at least one of the symptoms (cardiovascular manifestations, difficulty breathing, or gastrointestinal symptoms). Results: Of the 551 ColdU patients, 75% (n = 412) had a positive CST. Of them, concomitant chronic spontaneous urticaria was diagnosed in 10%. Of 372 patients with stand-alone ColdU, 69% were women and 91% adults. Their median age was 36 (IQR 26 - 48) years. Patients were also categorized into residents of countries with a tropical (n = 33), temperate (n = 264), or cold (n = 75) climate (Table 1: R13C1, R17C1, R21C1). AAI was more often prescribed to residents of temperate than tropical countries (30% vs. 12%, p = .038; Table 1: R31C1), although the frequency of ColdA did not significantly differ between these countries (44% vs. 42%, p = 1.000; R29C2). Residents of tropical countries had a higher frequency of ColdA induced by cold air than residents of temperate (36% vs. 12%, p = .001; R29C4) or cold (36% vs. 12%, p = .007; R25C4) countries. Cardiovascular manifestations induced by cold air were diagnosed in 33% (n = 11) of residents of tropical countries, but only 18% (n = 2) and 36% (n = 4) of them had received adrenaline and AAI, respectively (R13 - 15C7). Furthermore, hypotension and/or loss of consciousness induced by cold air occurred in 18% (n = 6) of patients, but only 17% (n = 1) received adrenaline (R13 - 14C10). ColdA was induced by complete cold water immersion in 9% (n = 3) of patients, and none of them received adrenaline treatment nor AAI (R13 - 15C3). Conclusion: Our findings suggest that ColdA is undertreated and call for changes in ColdU management.

Effects of pregnancy on chronic urticaria: Results of the PREG-CU UCARE study.

BACKGROUND: Chronic urticaria (CU) predominantly affects women, and sex hormones can modulate disease activity in female CU patients. As of now, the impact of pregnancy on CU is largely unknown. AIM: To analyze the course and features of CU during and after pregnancy. PATIENTS AND METHODS: PREG-CU is an international, multicenter study of the Urticaria Centers of Reference and Excellence (UCARE) network. Data were collected via a 47-item questionnaire completed by CU patients, who became pregnant within the last 3 years. RESULTS: A total of 288 pregnancies of 288 CU patients from 13 countries were analyzed (mean age at pregnancy: 32.1 ± 6.1 years, duration of CU: 84.9 ± 74.5 months; CSU 66.9%, CSU + CIndU 20.3%, CIndU 12.8%).During pregnancy, 51.1% of patients rated their CU as improved, 28.9% as worse, and 20.0% as unchanged.CU exacerbations most commonly occurred exclusively during the third trimester (in 34 of 124 patients; 27.6%) or the first (28 of 124; 22.8%). The risk factors for worsening of CU during pregnancy were having mild disease and no angioedema before pregnancy, not taking treatment before pregnancy, CIndU, CU worsening during a previous pregnancy, treatment during pregnancy, and stress as a driver of exacerbations. After giving birth, urticaria disease activity remained unchanged in 43.8% of CU patients, whereas 37.4% and 18.1% experienced worsening and improvement, respectively. CONCLUSIONS: These results demonstrate the complex impact of pregnancy on the course of CU and help to better counsel patients who want to become pregnant and to manage CU during pregnancy.

The complex role of mast cells in fungal infections.

In addition to their critical role in allergic disorders, mast cells (MCs) are well recognized for their protective effector functions during bacteria and parasite infections. This review describes recent advancements of our understanding of the complex role of MCs in fungal infections. Specifically, we outline key features of the contribution of MCs to infections with six fungal pathogens, namely Sporothrix, Paracoccidioides, Aspergillus, Malassezia, Candida and Dermatophytes. Evidence from studies of these pathogens suggests that MCs can function as positive regulators that detect and contain fungi at the site of infection. However, it appears that the inflammation induced by MCs following fungal infections may not always and only be beneficial to the host. MC responses during fungal infections may primarily benefit the pathogen by facilitating its spreading and contributing to a greater severity of fungal infections. This review also highlights key drivers of MCs activation and effector mechanisms that have been identified for the multidimensional function of MCs in fungal diseases and in allergic diseases combined with fungal infection.

Impaired Skin Barrier Function and Downregulated Expression of Caspase-14 in Moderate to Severe Chronic Hand Eczema.

AIM: To investigate whether the skin barrier function is impaired with regard to the pH value, water content, transepidermal water loss (TEWL), and the integrity of the stratum corneum, and whether the expression of caspase-14 is altered in moderate to severe chronic hand eczema (CHE). METHODS: Thirty patients with moderate to severe CHE treated at our institute and 30 healthy volunteers were included in this study. The pH value, water content, TEWL, and the integrity of the stratum corneum were measured in all subjects. RESULTS: Significantly increased pH value, decreased water content, elevated TEWL, and impaired integrity of the stratum corneum were observed in the lesional skin of CHE patients compared with the nonlesional skin of CHE patients and the normal skin of healthy volunteers. The expression of caspase-14 decreased in the lesional and nonlesional skin of CHE patients compared with the normal skin of healthy volunteers, especially prominent in the nonlesional skin. The mean optical density (OD) value of immunohistochemical staining for caspase-14 was significantly lower in the nonlesional skin than in the lesional skin and normal skin (p < 0.01 for both). Although the mean OD value was lower in the lesional skin than in the normal skin, the difference was not statistically significant (p > 0.05). CONCLUSION: Skin barrier dysfunction indeed occurs in CHE patients, which may be related to mechanisms associated with a downregulated expression of caspase-14.

Upregulated expression of substance P (SP) and NK1R in eczema and SP-induced mast cell accumulation.

Substance P (SP) was reported to be associated with eczema and acts as a potent skin mast cell secretagogue. However, little is known of its expression in inflammatory cells in eczema and its ability in induction of mast cell accumulation. In the present study, we investigated expression of SP and neurokinin-1 receptor (NK1R) on peripheral blood leukocytes and mast cells from patients with eczema and influence of SP on mast cell accumulation by using flow cytometry analysis, trans-epithelial cell migration assay and mouse peritoneal model. The results showed that plasma SP and IL-17A levels in eczema patients were higher than that in healthy control subject. The percentages of SP+ and NK1R+ expression populations of monocytes, helper T cells, natural killer T cells and basophils in peripheral blood of eczema patients were markedly elevated. It was observed that not only absolute number of mast cells but also SP+ and NK1R+ mast cells are enhanced in the lesion skin of eczema. SP showed a potent chemoattractant action on mast cells as assessed by a mouse peritoneal model and a trans-endothelium cell migration assay. SP-induced mast cell accumulation appears a CD18/CD11a complex, L-selectin and ICAM-1-dependent event which can be blocked by a NK-1R antagonist RP67580. In conclusion, elevated expression of SP in patients with eczema and the ability of SP in induction of mast cell accumulation indicate strongly that SP is a potent proinflammatory mediator, which contributes to the pathogenesis of eczema. Inhibitors of SP and blockers of NK1R are likely useful agents for treatment of eczema.

Omalizumab for the treatment of chronic spontaneous urticaria: A meta-analysis of randomized clinical trials.

BACKGROUND: Chronic spontaneous urticaria (CSU) is defined by itchy hives, angioedema, or both for at least 6 weeks. Omalizumab, an anti-IgE antibody that affects mast cell and basophil function, is a promising new treatment option. As of now, however, the efficacy and safety of different doses of omalizumab used in clinical trials for CSU have not been systematically analyzed and summarized. OBJECTIVE: We sought to assess the efficacy and safety of different doses of omalizumab for the treatment of CSU in a meta-analysis of clinical trial results. METHODS: Suitable trials were identified by searching PubMed, Medline, Embase, and Web of Science databases and with the help of omalizumab's manufacturers. Only double-blind, randomized, placebo-controlled studies with omalizumab-treated versus placebo-treated patients with CSU were included in this analysis. RESULTS: We identified 7 randomized, placebo-controlled studies with 1312 patients with CSU. Patients treated with omalizumab (75-600 mg every 4 weeks) had significantly reduced weekly itch and weekly wheal scores compared with the placebo group. Omalizumab's effects were dose dependent, with the strongest reduction in weekly itch and weekly wheal scores observed with 300 mg. Rates of complete response were significantly higher in the omalizumab group (relative risk, 4.55; P < .00001) and dose dependent, with the highest rates in the 300-mg group. Rates of patients with adverse events were similar in the omalizumab and placebo groups. CONCLUSION: This meta-analysis provides high-quality evidence for the efficacy and safety of omalizumab in patients with CSU and for treating these patients with 300 mg of omalizumab every 4 weeks.

International Society of Human and Animal Mycology (ISHAM)-ITS reference DNA barcoding database--the quality controlled standard tool for routine identification of human and animal pathogenic fungi.

Human and animal fungal pathogens are a growing threat worldwide leading to emerging infections and creating new risks for established ones. There is a growing need for a rapid and accurate identification of pathogens to enable early diagnosis and targeted antifungal therapy. Morphological and biochemical identification methods are time-consuming and require trained experts. Alternatively, molecular methods, such as DNA barcoding, a powerful and easy tool for rapid monophasic identification, offer a practical approach for species identification and less demanding in terms of taxonomical expertise. However, its wide-spread use is still limited by a lack of quality-controlled reference databases and the evolving recognition and definition of new fungal species/complexes. An international consortium of medical mycology laboratories was formed aiming to establish a quality controlled ITS database under the umbrella of the ISHAM working group on "DNA barcoding of human and animal pathogenic fungi." A new database, containing 2800 ITS sequences representing 421 fungal species, providing the medical community with a freely accessible tool at http://www.isham.org/ and http://its.mycologylab.org/ to rapidly and reliably identify most agents of mycoses, was established. The generated sequences included in the new database were used to evaluate the variation and overall utility of the ITS region for the identification of pathogenic fungi at intra-and interspecies level. The average intraspecies variation ranged from 0 to 2.25%. This highlighted selected pathogenic fungal species, such as the dermatophytes and emerging yeast, for which additional molecular methods/genetic markers are required for their reliable identification from clinical and veterinary specimens.