Cancer SLC6A6-mediated taurine uptake transactivates immune checkpoint genes and induces exhaustion in CD8+ T cells.

Taurine is used to bolster immunity, but its effects on antitumor immunity are unclear. Here, we report that cancer-related taurine consumption causes T cell exhaustion and tumor progression. The taurine transporter SLC6A6 is correlated with aggressiveness and poor outcomes in multiple cancers. SLC6A6-mediated taurine uptake promotes the malignant behaviors of tumor cells but also increases the survival and effector function of CD8+ T cells. Tumor cells outcompete CD8+ T cells for taurine by overexpressing SLC6A6, which induces T cell death and malfunction, thereby fueling tumor progression. Mechanistically, taurine deficiency in CD8+ T cells increases ER stress, promoting ATF4 transcription in a PERK-JAK1-STAT3 signaling-dependent manner. Increased ATF4 transactivates multiple immune checkpoint genes and induces T cell exhaustion. In gastric cancer, we identify a chemotherapy-induced SP1-SLC6A6 regulatory axis. Our findings suggest that tumoral-SLC6A6-mediated taurine deficiency promotes immune evasion and that taurine supplementation reinvigorates exhausted CD8+ T cells and increases the efficacy of cancer therapies.

miR-107 reverses the multidrug resistance of gastric cancer by targeting the CGA/EGFR/GATA2 positive feedback circuit.

Chemotherapy is still the main therapeutic strategy for gastric cancer (GC). However, most patients eventually acquire multidrug resistance (MDR). Hyperactivation of the EGFR signaling pathway contributes to MDR by promoting cancer cell proliferation and inhibiting apoptosis. We previously identified the secreted protein CGA as a novel ligand of EGFR and revealed a CGA/EGFR/GATA2 positive feedback circuit that confers MDR in GC. Herein, we outline a microRNA-based treatment approach for MDR reversal that targets both CGA and GATA2. We observed increased expression of CGA and GATA2 and increased activation of EGFR in GC samples. Bioinformatic analysis revealed that miR-107 could simultaneously target CGA and GATA2, and the low expression of miR-107 was correlated with poor prognosis in GC patients. The direct interactions between miR-107 and CGA or GATA2 were validated by luciferase reporter assays and western blot analysis. Overexpression of miR-107 in MDR GC cells increased their susceptibility to chemotherapeutic agents, including fluorouracil, adriamycin and vincristine, in vitro. Notably, intratumor injection of the miR-107 prodrug enhanced MDR xenograft sensitivity to chemotherapies in vivo. Molecularly, targeting CGA and GATA2 with miR-107 inhibited EGFR downstream signaling, as evidenced by the reduced phosphorylation of ERK and AKT. These results suggest that miR-107 may contribute to the development of a promising therapeutic approach for the treatment of MDR in GC.

Fibroblasts in immune-mediated inflammatory diseases: The soil of inflammation.

As one of the most abundant stromal cells, fibroblasts are primarily responsible for the production and remodeling of the extracellular matrix. Traditionally, fibroblasts have been viewed as quiescent cells. However, recent advances in multi-omics technologies have demonstrated that fibroblasts exhibit remarkable functional diversity at the single-cell level. Additionally, fibroblasts are heterogeneous in their origins, tissue locations, and transitions with stromal cells. The dynamic nature of fibroblasts is further underscored by the fact that disease stages can impact their heterogeneity and behavior, particularly in immune-mediated inflammatory diseases such as psoriasis, inflammatory bowel diseases, and rheumatoid arthritis, etc. Fibroblasts can actively contribute to the disease initiation, progression, and relapse by responding to local microenvironmental signals, secreting downstream inflammatory factors, and interacting with immune cells during the pathological process. Here we focus on the development, plasticity, and heterogeneity of fibroblasts in inflammation, emphasizing the need for a developmental and dynamic perspective on fibroblasts.

Formylpeptide receptor 1 contributes to epidermal barrier dysfunction-induced skin inflammation through NOD-like receptor C4-dependent keratinocyte activation.

BACKGROUND: Skin barrier dysfunction may both initiate and aggravate skin inflammation. However, the mechanisms involved in the inflammation process remain largely unknown. OBJECTIVES: We sought to determine how skin barrier dysfunction enhances skin inflammation and molecular mechanisms. METHODS: Skin barrier defect mice were established by tape stripping or topical use of acetone on wildtype mice, or filaggrin deficiency. RNA-Seq was employed to analyse the differentially expressed genes in mice with skin barrier defects. Primary human keratinocytes were transfected with formylpeptide receptor (FPR)1 or protein kinase R-like endoplasmic reticulum (ER) kinase (PERK) small interfering RNA to examine the effects of these gene targets. The expressions of inflammasome NOD-like receptor (NLR)C4, epidermal barrier genes and inflammatory mediators were evaluated. RESULTS: Mechanical (tape stripping), chemical (acetone) or genetic (filaggrin deficiency) barrier disruption in mice amplified the expression of proinflammatory genes, with transcriptomic profiling revealing overexpression of formylpeptide receptor (Fpr1) in the epidermis. Treatment with the FPR1 agonist fMLP in keratinocytes upregulated the expression of the NLRC4 inflammasome and increased interleukin-1ß secretion through modulation of ER stress via the PERK-eIF2α-C/EBP homologous protein pathway. The activation of the FPR1-NLRC4 axis was also observed in skin specimens from old healthy individuals with skin barrier defect or elderly mice. Conversely, topical administration with a FPR1 antagonist, or Nlrc4 silencing, led to the normalization of barrier dysfunction and alleviation of inflammatory skin responses in vivo. CONCLUSIONS: In summary, our findings show that the FPR1-NLRC4 inflammasome axis is activated upon skin barrier disruption and may explain exaggerated inflammatory responses that are observed in disease states characterized by epidermal dysfunction. Pharmacological inhibition of FPR1 or NLRC4 represents a potential therapeutic target.

Optimal folic acid dosage in lowering homocysteine: Precision Folic Acid Trial to lower homocysteine (PFAT-Hcy).

BACKGROUND: While folic acid (FA) is widely used to treat elevated total homocysteine (tHcy), promoting vascular health by reducing vascular oxidative stress and modulating endothelial nitric oxide synthase, the optimal daily dose and individual variation by MTHFR C677T genotypes have not been well studied. Therefore, this study aimed to explore the efficacy of eight different FA dosages on tHcy lowering in the overall sample and by MTHFR C677T genotypes. METHODS: This multicentered, randomized, double-blind, controlled clinical trial included 2697 eligible hypertensive adults with elevated tHcy (≥ 10 mmol/L) and without history of stroke and cardiovascular disease. Participants were randomized into eight dose groups of FA combined with 10 mg enalapril maleate, taken daily for 8 weeks of treatment. RESULTS: The intent to treat analysis included 2163 participants. In the overall sample, increasing FA dosage led to steady tHcy reduction within the FA dosing range of 0-1.2 mg. However, a plateau in tHcy lowering was observed in FA dose range of 1.2-1.6 mg, indicating a ceiling effect. In contrast, FA doses were positively and linearly associated with serum folate levels without signs of plateau. Among MTHFR genotype subgroups, participants with the TT genotype showed greater efficacy of FA in tHcy lowering. CONCLUSIONS: This randomized trial lent further support to the efficacy of FA in lowering tHcy; more importantly, it provided critically needed evidence to inform optimal FA dosage. We found that the efficacy of FA in lowering tHcy reaches a plateau if the daily dosage exceeds 1.2 mg, and only has a small gain by increasing the dosage from 0.8 to 1.2 mg. GOV IDENTIFIER: NCT03472508 (Registration Date: March 21, 2018).

Application of Biosurfactants in Medical Sciences.

Biosurfactants derived from microorganisms have attracted widespread attention in scientific research due to their unique surface activity, low toxicity, biodegradability, antibacterial properties, and stability under extreme conditions. Biosurfactants are widely used in many fields, such as medicine, agriculture, and environmental protection. Therefore, this review aims to comprehensively review and analyze the various applications of biosurfactants in the medical field. The central roles of biosurfactants in crucial medical areas are explored, like drug delivery, induction of tumor cell differentiation or death, treating bacterial and viral effects, healing wounds, and immune regulation. Moreover, a new outlook is introduced on optimizing the capabilities of biosurfactants through modification and gene recombination for better use in medicine. The current research challenges and future research directions are described, aiming to provide valuable insights for continuous study of biosurfactants in medicine.

The Slack Channel Regulates Anxiety-Like Behaviors via Basolateral Amygdala Glutamatergic Projections to Ventral Hippocampus.

Anxiety disorders are a series of mental disorders characterized by anxiety and fear, but the molecular basis of these disorders remains unclear. In the present study, we find that the global Slack KO male mice exhibit anxious behaviors, whereas the Slack Y777H male mice manifest anxiolytic behaviors. The expression of Slack channels is rich in basolateral amygdala (BLA) glutamatergic neurons and downregulated in chronic corticosterone-treated mice. In addition, electrophysiological data show enhanced excitability of BLA glutamatergic neurons in the Slack KO mice and decreased excitability of these neurons in the Slack Y777H mice. Furthermore, the Slack channel deletion in BLA glutamatergic neurons is sufficient to result in enhanced avoidance behaviors, whereas Kcnt1 gene expression in the BLA or BLA-ventral hippocampus (vHPC) glutamatergic projections reverses anxious behaviors of the Slack KO mice. Our study identifies the role of the Slack channel in controlling anxious behaviors by decreasing the excitability of BLA-vHPC glutamatergic projections, providing a potential target for anxiolytic therapies.SIGNIFICANCE STATEMENT Anxiety disorders are a series of mental disorders characterized by anxiety and fear, but the molecular basis of these disorders remains unclear. Here, we examined the behaviors of loss- and gain-of-function of Slack channel mice in elevated plus maze and open field tests and found the anxiolytic role of the Slack channel. By altering the Slack channel expression in the specific neuronal circuit, we demonstrated that the Slack channel played its anxiolytic role by decreasing the excitability of BLA-vHPC glutamatergic projections. Our data reveal the role of the Slack channel in the regulation of anxiety, which may provide a potential molecular target for anxiolytic therapies.

Wnt signaling modulator DKK4 inhibits colorectal cancer metastasis through an AKT/Wnt/ß-catenin negative feedback pathway.

Aberrant activation of the Wnt/ß-catenin signaling pathway is implicated in most malignant cancers, especially in the initiation and progression of colorectal cancer (CRC). DKK4 is a classical inhibitory molecule of the Wnt/ß-catenin pathway, but its role in CRC is ambiguous, and the molecular mechanism remains unclear. Here, we determined DKK4 expression was significantly upregulated in 23 CRC cell lines and 229 CRC tissues when analyzed by quantitative PCR and immunohistochemistry, respectively. Our analysis of tissue samples indicated the survival time of CRC patients with high DKK4 expression was longer than that of patients with medium-low DKK4 expression. We examined the effects of DKK4 on cell proliferation and metastasis by cell counting kit-8 assays, transwell assays, and subcutaneous and metastatic mouse tumor models, and we discovered that DKK4 silencing promoted the metastasis of CRC cells both in vitro and in vivo. Our RNA-seq analysis revealed that AKT2, FZD6, and JUN, which play important roles in AKT and Wnt signaling, were significantly increased after DKK4 knockdown. DKK4 represses Wnt/ß-catenin signaling by repressing FZD6 and AKT2/s552 ß-catenin in CRC. Further experiments revealed recombinant Wnt3a and LiCl could induce DKK4 expression. Moreover, our bioinformatics analysis and luciferase reporter assays identified posttranscriptional regulators of DKK4 in CRC cells. In summary, DKK4 is elevated in CRC and inhibits cell metastasis by a novel negative feedback mechanism of the Wnt3a/DKK4/AKT/s552 ß-catenin regulatory axis to restrict overactivation of Wnt activity in CRC. Therefore, DKK4 restoration may be applied as a potential CRC therapeutic strategy.

Cross-disease characterization of fibroblast heterogeneities and their pathogenic roles in skin inflammation.

Fibroblasts are critical pro-inflammatory regulators in chronic inflammatory and fibrotic skin diseases. However, fibroblast heterogeneity and the absence of a unified cross-disease taxonomy have hindered our understanding of the shared/distinct pathways in non-communicable skin inflammation. By integrating 10× single-cell data from 75 skin samples, we constructed a single-cell atlas across inflammatory and fibrotic skin diseases and identified 9 distinct subsets of skin fibroblasts. We found a shared subset of CCL19+ fibroblasts across these diseases, potentially attracting and educating immune cells. Moreover, COL6A5+ fibroblasts were a distinct subset implicated in the initiation and relapse of psoriasis, which tended to differentiate into CXCL1+ fibroblasts, inducing neutrophil chemotaxis and infiltration; while CXCL1+ fibroblasts exhibited a more heterogeneous response to certain inflammatory conditions. Differentiation trajectory and regulatory factors of these fibroblast subsets were also revealed. Therefore, our study presents a comprehensive atlas of skin fibroblasts and highlights pathogenic fibroblast subsets in skin disorders.

High-performance and compact integrated photonic dichroic filters and triplexer realized by an efficient inverse design.

Integrated optical filters are key components in various photonic integrated circuits for applications of communication, spectroscopy, etc. The dichroic filters can be flexibly cascaded to construct filters with various channel numbers and bandwidths. Therefore, the development of high-performance and compact dichroic filters is crucial. In this work, we develop the dichroic filters with 1.49/1.55-µm channels by an inverse design. Benefiting from a search-space-dimension control strategy and advanced optimization algorithm, our efficient design method results in two high-performance dichroic filters without and with subwavelength gratings (SWGs). The comparison suggests that SWGs in filters can be useful for loss reduction and footprint compression by dispersion engineering. The developed dichroic filter with SWGs exhibits measured bandwidths of 26/29 nm, excess losses of < 0.5 dB, and crosstalks of <-10 dB with a compact footprint of 2.5 × 22.0 µm2. It has advantages in performance or compactness compared to the previously reported counterparts. A triplexer with a footprint of 10.5 × 117 µm2 is developed based on the dichroic filters, also showing decent overall performance and compactness.

Neutrophil extracellular traps promote keratinocyte inflammation via AIM2 inflammasome and AIM2-XIAP in psoriasis.

The infiltration of neutrophils in the epidermis and the release of neutrophil extracellular traps (NETs) are important events in the pathogenesis of psoriasis, but the regulatory roles and internal mechanism of NETs in psoriasis are largely unknown. Here, we demonstrate that NETs can activate the absent-in-melanoma-2 (AIM2) inflammasome in keratinocytes through the p38-MAPK signalling pathway, and targeting NETs with CI-amidine in vivo reduces AIM2 expression and ameliorates imiquimod-induced psoriasis-like phenotype in mice. Notably, NETs-activated AIM2 in keratinocytes not only promotes IL-1ß production through the classical inflammasome pathway but also promotes IFN-γ production via X-linked inhibitor of apoptosis protein (XIAP), thereby mediating the immune responses of keratinocytes. In conclusion, our study demonstrates that the NETs-AIM2 axis exerts multiple pro-inflammatory effects on keratinocytes and may serve as a potential target for psoriasis therapy.

ROS-Activated TRPM2 Channel: Calcium Homeostasis in Cardiovascular/renal System and Speculation in Cardiorenal Syndrome.

The transient receptor potential melastatin 2 (TRPM2) channel is a nonselective calcium channel that is sensitive to oxidative stress (OS), and is widely expressed in multiple organs, such as the heart, kidney, and brain, which is inextricably related to calcium dyshomeostasis and downstream pathological events. Due to the increasing global burden of kidney or cardiovascular diseases (CVDs), safe and efficient drugs specific to novel targets are imperatively needed. Notably, investigation of the possibility to regard the TRPM2 channel as a new therapeutic target in ROS-related CVDs or renal diseases is urgently required because the roles of the TRPM2 channel in heart or kidney diseases have not received enough attention and thus have not been fully elaborated. Therefore, we aimed to review the involvement of the TRPM2 channel in cardiovascular disorders related to kidney or typical renal diseases and attempted to speculate about TRPM2-mediated mechanisms of cardiorenal syndrome (CRS) to provide representative perspectives for future research about novel and effective therapeutic strategies.

Simultaneous thulium laser resection of the prostate and transperineal prostate biopsy in clinically diagnosed metastatic prostate cancer with bladder outlet obstruction.

Metastatic prostate cancer (mPCa) patients complicated with bladder outlet obstruction (BOO) are often referred to a urologist. Androgen deprivation therapy (ADT) combined with indwelling catheter usually be the initial management. To retrospectively analysis the safety and efficacy of simultaneous thulium laser resection of the prostate (TmLRP) and transperineal prostate biopsy in metastatic prostate cancer with bladder outlet obstruction. From January 2016 to December 2021, 67 clinically diagnosed mPCa with BOO patients were included in this study. All patients were preoperatively assessed with international prostate symptom score (IPSS), QoL, serum prostate-specific antigen (PSA), prostate volume evaluation by transrectal ultrasound, postvoid residual urine volume (PVR), and maximum flow rate (Qmax). Preoperative and perioperative parameters at 1-, 3-, and 6-month follow-up were also evaluated. All complications were recorded. Simultaneous TmLRP and transperineal prostate biopsy had obvious advantages for clinically diagnosed mPCa patients with BOO, including short overall operation time (52 ± 23.3 min), little hemoglobin decrease (0.6 ± 0.7 g/l), and short hospital stay (average 3.8 days). In addition, simultaneous TmLRP and transperineal prostate biopsy also brought them significant improvement on IPSS, QoL score, Qmax, and PVR volume (P < 0.001) at 1-, 3-, and 6-month follow-up after operation compared to preoperative parameters. Complications were in a low incidence. Simultaneous TmLRP and transperineal prostate biopsy is a bloodless operation with immediate effect and little perioperative complication. Importantly, it is a promising technology in the diagnosis and treatment of clinically diagnosed mPCa patients with BOO.

Neutrophil extracellular traps contribute to immune dysregulation in bullous pemphigoid via inducing B-cell differentiation and antibody production.

Bullous pemphigoid (BP), an autoimmune skin disease, is characterized by autoantibodies against hemidesmosomal proteins in the skin and mucous membranes. Neutrophils infiltrate BP skin lesions, however, their role in immune dysregulation remains unclear. We investigated whether BP involves aberrant neutrophil extracellular traps (NETs) formation in skin lesions and circulation; and examined the triggers and deleterious immuno-inflammatory consequences. In the present study, we found that circulating NET-related biomarker levels increased in serum and blister fluid of BP patients and significantly correlated with disease severity. Additionally, circulating neutrophils from BP patients displayed enhanced spontaneous NETs formation than healthy controls. In vitro, BP180-NC16A immune complexes-induced NETosis in neutrophils from BP patients, which was abrogated by Fcγ receptor and/or NADPH pathway blockade. Furthermore, the elevated levels of NETs from BP patients boosted autoantibody production by inducing B-cell differentiation into plasma cells, mediated by MAPK P38 cascade activation. Together, our findings provide strong evidence that NETs are involved in a pathogenic loop, causing excessive differentiation of B cells and promotion of autoantibody production. Hence, targeting aberrant neutrophil responses will provide novel potential targets for the treatment of BP.

Broad-spectrum antiviral activity of Spatholobus suberectus Dunn against SARS-CoV-2, SARS-CoV-1, H5N1, and other enveloped viruses.

The current COVID-19 pandemic caused by SARS-Cov-2 is responsible for more than 6 million deaths globally. The development of broad-spectrum and cost-effective antivirals is urgently needed. Medicinal plants are renowned as a complementary approach in which antiviral natural products have been established as safe and effective drugs. Here, we report that the percolation extract of Spatholobus suberectus Dunn (SSP) is a broad-spectrum viral entry inhibitor against SARS-CoV-1/2 and other enveloped viruses. The viral inhibitory activities of the SSP were evaluated by using pseudotyped SARS-CoV-1 and 2, HIV-1ADA and HXB2 , and H5N1. SSP effectively inhibited viral entry and with EC50 values ranging from 3.6 to 5.1 µg/ml. Pre-treatment of pseudovirus or target cells with SSP showed consistent inhibitory activities with the respective EC50 value of 2.3 or 2.1 µg/ml. SSP blocked both SARS-CoV-2 spike glycoprotein and the host ACE2 receptor. In vivo studies indicated that there was no abnormal toxicity and behavior in long-term SSP treatment. Based on these findings, we concluded that SSP has the potential to be developed as a drug candidate for preventing and treating COVID-19 and other emerging enveloped viruses.

Adaptive Recognition of Bioacoustic Signals in Smart Aquaculture Engineering Based on r-Sigmoid and Higher-Order Cumulants.

In recent years, interest in aquaculture acoustic signal has risen since the development of precision agriculture technology. Underwater acoustic signals are known to be noisy, especially as they are inevitably mixed with a large amount of environmental background noise, causing severe interference in the extraction of signal features and the revelation of internal laws. Furthermore, interference adds a considerable burden on the transmission, storage, and processing of data. A signal recognition curve (SRC) algorithm is proposed based on higher-order cumulants (HOC) and a recognition-sigmoid function for feature extraction of target signals. The signal data of interest can be accurately identified using the SRC. The analysis and verification of the algorithm are carried out in this study. The results show that when the SNR is greater than 7 dB, the SRC algorithm is effective, and the performance improvement is maximized when the SNR is 11 dB. Furthermore, the SRC algorithm has shown better flexibility and robustness in application.

Regulation of the small GTPase Ran by miR-802 modulates proliferation and metastasis in colorectal cancer cells.

BACKGROUND: The small GTPase Ran is upregulated in multiple cancers and fundamental for cancer cell survival and progression, but its significance and molecular mechanisms in colorectal cancer (CRC) remain elusive. METHODS: Ran expression was detected in CRC cell lines and tumour tissues. In vitro and in vivo functional assays were performed to examine the effects of Ran on cell proliferation and metastasis. The pathways and effectors regulated by Ran were explored by an unbiased screening. Bioinformatics prediction and experimental validation were used to identify the miRNA regulator for Ran. RESULTS: Ran expression was frequently increased in metastatic CRC cells and tissues, especially in metastatic tissues. The upregulation of Ran correlated with poor CRC patient prognosis. Ran silencing reduced proliferation and metastasis of CRC cells both in vitro and in vivo. Ran regulated the expression of EGFR and activation of ERK and AKT signalling pathways. miR-802 was identified as an upstream regulator of Ran and miR-802 overexpression resulted in antiproliferative and antimetastatic activities. CONCLUSION: Our study demonstrates the oncogenic roles and underlying mechanisms of Ran in CRC and the novel miR-802/Ran/EGFR regulatory axis may provide potential biomarkers for the treatment of CRC.

Clinical analysis of adrenal lesions larger than 5 cm in diameter (an analysis of 251 cases).

BACKGROUND: To describe the pathological distribution, imaging manifestations, and surgical managements and prognosis of large adrenal tumors (LATs) ≥ 5 cm METHODS: A total of 251 patients with LATs were analyzed on the basis of pathological or clinical diagnosis. Regarding surgery, open adrenalectomy was performed on 89 patients, and laparoscopic adrenalectomy was performed on 89 patients. Thirty-two patients with bilateral tumors were analyzed in terms of clinical characteristics. The survival rate was determined for 43 patients with adrenal metastases and 29 patients with primary adrenal malignancies. The CT characteristics including tumor diameter, shape, edge, heterogeneity, necrosis, calcification, pre-contrast attenuation, and contrast attenuation were analyzed for 117 patients. RESULTS: The majority of LATs were still benign, but they had a higher probability to be malignant. Benign LATs made up 68.13% of all cases, mainly adrenal cysts (19.52%), pheochromocytoma (18.73%), benign adenoma (16.73%), and myelolipoma (7.17%). Malignant LATs accounted for 28.69% of cases, mainly including adrenocortical carcinoma (8.76%) and metastases (17.13%). Laparoscopic surgery was found to involve less trauma than open surgery. It was also safer and postoperative recovery was faster, but it had drawbacks and could not completely replace open surgery. CT features had obvious specificity for the diagnosis of benign and malignant tumors. For example, benign adenomas had a smaller pre-contrast (< 10 Hu) whereas malignant adrenal tumors had, on the contrary, higher attenuation. Regarding adrenal malignant carcinoma, adrenal primary malignant tumors showed a better prognosis than adrenal metastases (mean survival of 19.17 months vs 9.49 months). Primary adrenal cortical carcinoma without metastasis had a better prognosis than primary adrenal cortical carcinoma metastasis (mean survival of 23.71 months vs 12.75 months), and adrenal solitary metastasis had a better prognosis than general multiple metastatic carcinoma (mean survival of 14.95 months vs 5.17 months). CONCLUSION: LATs were more likely to be benign; however, they still had a high probability of being a malignant tumor. Understanding the clinicopathological characteristics of LATs can facilitate selection of more effective clinical treatment options.

Proinflammatory effect of high-mobility group protein B1 on keratinocytes: an autocrine mechanism underlying psoriasis development.

Psoriasis is an autoimmune skin disease, in which keratinocytes play a crucial pathogenic role. High-mobility group protein B1 (HMGB1) is an inflammatory factor that can be released from keratinocyte nuclei in psoriatic lesions. We aimed to investigate the proinflammatory effect of HMGB1 on keratinocytes and the contribution of HMGB1 to psoriasis development. Normal human keratinocytes were treated with recombinant human HMGB1, and the production of inflammatory factors and the intermediary signalling pathways were examined. Furthermore, the imiquimod-induced psoriasis-like mouse model was used to investigate the role of HMGB1 in psoriasis development in vivo. A total of 11 inflammatory factors were shown to be upregulated by HMGB1 in keratinocytes, among which interleukin (IL)-18 showed the greatest change. We then found that activation of the nuclear factor-κB signalling pathway and inflammasomes accounted for HMGB1-induced IL-18 expression and secretion. Moreover, HMGB1 and downstream IL-18 contributed to the development of psoriasiform dermatitis in the imiquimod-treated mice. In addition, T-helper 17 immune response in the psoriasis-like mouse model could be inhibited by both HMGB1 and IL-18 blockade. Our findings indicate that HMGB1 secreted from keratinocytes can facilitate the production and secretion of inflammatory factors such as IL-18 in keratinocytes in an autocrine way, thus promoting the development of psoriasis. Blocking the proinflammatory function of the HMGB1-IL-18 axis may be useful for psoriasis treatment in the future. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.