Severe congenital neutropenia (SCN) comprises a diverse range of rare hematological disorders characterized by recurrent, often life-threatening infections that manifest within the first months of life. Mutations in the ELANE gene are the most prevalent cause of SCN. While over 230 mutations in ELANE have been documented, including substitutions, frameshifts, nonsense mutations, and splice site alterations, the occurrence of deep intronic mutations has not been previously reported. Herein, we present the case of a young girl who exhibited recurrent fever, respiratory infections, skin abscesses, and gingivitis shortly after birth. Laboratory analysis revealed markedly diminished neutrophil levels alongside elevated monocyte and eosinophil counts. Bone marrow examination disclosed a halt in myelopoiesis maturation. ELANE gene full-length sequencing identified a novel de novo deep intron mutation in ELANE (c.598 + 79G > T), subsequently confirmed by Sanger sequencing. cDNA sequencing of the patient demonstrated aberrant gene splicing. Utilizing a mini-gene splicing assay for ELANE intronic variants, we identified a mutant ELANE allele (c.597 + 1_597 + 83ins) leading to the creation of a premature termination codon (p.Gly200ValfsTer40). Confocal microscopy revealed heightened expression of myeloperoxidase and neutrophil elastase in the patient, suggesting a potential role for the unfolded protein response in the pathogenesis of the deep intron ELANE mutation. In summary, our findings illustrate the first reported instance of de novo deep intron ELANE mutations associated with SCN, underscoring the importance of exploring deep intronic regions in SCN patients lacking identifiable disease-causing gene mutations.

OBJECTIVE: Sepsis pathophysiology is complex and identifying effective treatments for sepsis remains challenging. The study aims to identify effective drugs and targets for sepsis through transcriptomic analysis of sepsis patients, repositioning analysis of compounds, and validation by animal models.
METHODS: GSE185263 obtained from the GEO database that includes gene expression profiles of 44 healthy controls and 348 sepsis patients categorized by severity. Bioinformatic algorithms revealed the molecular, function, and immune characteristics of the sepsis, and constructed sepsis-related protein-protein interaction networks. Subsequently, Random Walk with Restart analysis was applied to identify candidate drugs for sepsis, which were tested in animal models for survival, inflammation, coagulation, and multi-organ damage.
RESULTS: Our analysis found 1862 genes linked to sepsis development, enriched in functions like neutrophil extracellular trap formation (NETs) and complement/coagulation cascades. With disease progression, immune activation-associated cells were inhibited, while immune suppression-associated cells were activated. Next, the drug repositioning method identified candidate drugs, such as alpha-1 antitrypsin, that may play a therapeutic role by targeting neutrophil elastase (NE) to inhibit NETs. Animal experiments proved that alpha-1 antitrypsin treatment can improve the survival rate, reduce sepsis score, reduce the levels of inflammation markers in serum, and alleviate muti-organ morphological damage in mice with sepsis. The further results showed that α-1 antitrypsin can inhibit the NETs by suppressing the NE for the treatment of sepsis.
CONCLUSIONS: Alpha-1 antitrypsin acted on the NE to inhibit NETs thereby protecting mice from sepsis-induced inflammation and coagulation.

OBJECTIVE: To explore whether sivelestat sodium could reduce the expression of mucin 5AC (MUC5AC) in intrahepatic bile duct epithelial cells by inhibiting neutrophil elastase (NE) and thus provide new potential therapeutic ideas for the treatment of intrahepatic bile duct stone (IBDS).
METHODS: (1) Bioinformatics analysis: differential gene analysis was performed on gallbladder stone cholecystitis sequencing data based on the gene expression omnibus (GEO) to screen for significantly different genes related to neutrophils and mucins. The search tool for the retrieval of interacting genes database (STRING) was used for protein interaction analysis to predict whether there was an interaction between NE and MUC5AC genes. (2) Animal experiment: a total of 18 male SD rats were divided into the sham-operated group, cholangitis model group and sivelestat sodium treatment group according to the random number table method, with 6 rats in each group. The cholangitis rat model was established by a one-time injection of 1.25 mg/kg lipopolysaccharide (LPS) into the right anterior lobe of the liver of rats in combination with the pre-experiment; the liver of the sham-operated group was injected with an equal volume of saline. After the modelling, 100 mg/kg of sivelestat sodium was injected into the tail vein of the cevalexin treatment group once a day for 5 days, and an equal volume of saline was injected into the tail vein of the sham-operated group and the cholangitis model group. Two weeks later, the rats were euthanized and their liver and bile duct tissues were taken. The pathological changes in the liver and bile duct tissues were observed under the light microscope. Immunohistochemical staining was used to detect the expressions of NE and MUC5AC in liver and bile duct tissues. The protein expressions of NE, MUC5AC and Toll-like receptor 4 (TLR4) were detected by Western blotting. (3) Cell experiment: primary human intrahepatic biliary epithelial cell line (HiBEpiC) was divided into blank control group, NE group (10 nmol/L NE), NE+sivelestat sodium low dose group (10 nmol/L NE+1×10-8 g/L sivelestat sodium 1 mL), NE+sivelestat sodium medium dose group (10 nmol/L NE+1×10-7 g/L sivelestat sodium 1 mL), NE+sivelestat sodium high dose group (10 nmol/L NE+1×10-6 g/L sivelestat sodium 1 mL). Cells were collected after 48 hours of culture, and EdU was performed to detect the proliferative activity of cells; enzyme linked immunosorbent assay (ELISA) and Western blotting were performed to detect the expression of MUC5AC in cells.
RESULTS: (1) Bioinformatics analysis: the NE gene (ELANE) had a reciprocal relationship with MUC5AC. (2) Animal experiment: light microscopy showed that hepatocyte edema, hepatocyte diffuse point and focal necrosis, confluent area fibrous tissue and intrahepatic bile ducts hyperplasia and inflammatory cell infiltration in the cholangitis model group; hepatic lobule structure of sivelestat sodium treatment group was clear, and the degree of peripheral inflammatory cell infiltration was reduced compared with the cholangitis model group. Immunohistochemical staining showed that the expressions of NE and MUC5AC were increased in the cholangitis model group compared with the sham-operated group, and the expressions of NE and MUC5AC were decreased in the sivelestat sodium group compared with the cholangitis model group [NE (A value): 5.23±2.02 vs. 116.67±23.06, MUC5AC (A value): 5.40±3.09 vs. 23.81±7.09, both P < 0.05]. Western blotting showed that the protein expressions of NE, MUC5AC, and TLR4 in the hepatic biliary tissues of the cholangitis model group were significantly higher than those of the sham-operated group; and the protein expressions of NE, MUC5AC, and TLR4 in the liver biliary tissues of the sivelestat sodium treatment group were significantly higher than those of the sham-operated group (NE/β-actin: 0.38±0.04 vs. 0.70±0.10, MUC5AC/β-actin: 0.37±0.03 vs. 0.61±0.05, TLR4/β-actin: 0.39±0.10 vs. 0.93±0.15, all P < 0.05). (3) Cell experiment: fluorescence microscopy showed that the proliferation of HiBEpiC cells in each group was good, and there was no significant difference in the proportion of positive cells. ELISA and Western blotting showed that the expressions of MUC5AC in cells of the NE group were significantly higher than those of the blank control group. The expressions of MUC5AC in the NE+different dose of sivelestat sodium group were significantly lower than those in the NE group, and showed a decreasing trend with the increase of sevastatin sodium concentration, especially in the highest dose group [MUC5AC (μg/L): 3.46±0.20 vs. 6.33±0.52, MUC5AC/β-actin: 0.45±0.07 vs. 1.75±0.10, both P < 0.05].
CONCLUSIONS: LPS can upregulate the expression of NE and MUC5AC in rats with cholangitis, while sodium sivelestat can reduce the expression of MUC5AC in in intrahepatic biliary epithelial cells by inhibiting NE, providing a new direction for the treatment of IBDS.

Acanthopanacis cortex (the dried root bark of Acanthopanax gracilistylus W. W. Smith) has been used for the treatment of rheumatic diseases in China for over 2000 years. Four previously undescribed lignans (1-4) and 12 known lignans (5-16) were isolated from Acanthopanacis cortex. In this study, the inhibitory activities of compounds 1-16 against neutrophil elastase (NE), cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2) are reported. The results show that compounds 1-16 exhibit weak inhibitory activities against NE and COX-1. However, compounds 2, 6-8 and 13-16 demonstrate better COX-2 inhibitory effects with IC50 values from 0.75 to 8.17 μΜ. These findings provide useful information for the search for natural selective COX-2 inhibitors.

B-1a cells, an innate-like cell population, are crucial for pathogen defense and the regulation of inflammation through their release of natural IgM and IL-10. In sepsis, B-1a cell numbers are decreased in the peritoneal cavity as they robustly migrate to the spleen. Within the spleen, migrating B-1a cells differentiate into plasma cells, leading to alterations in their original phenotype and functionality. We discovered a key player, sialic acid-binding immunoglobulin-like lectin-G (Siglec-G), which is expressed predominantly on B-1a cells and negatively regulates B-1a cell migration to maintain homeostasis. Siglec-G interacts with CXCR4/CXCL12 to modulate B-1a cell migration. Neutrophils aid B-1a cell migration via neutrophil elastase (NE)-mediated Siglec-G cleavage. Human studies revealed increased NE expression in septic patients. We identified an NE cleavage sequence in silico, leading to the discovery of a decoy peptide that protects Siglec-G, preserves peritoneal B-1a cells, reduces inflammation, and enhances sepsis survival. The role of Siglec-G in inhibiting B-1a cell migration to maintain their inherent phenotype and function is compromised by NE in sepsis, offering valuable insights into B-1a cell homeostasis. Employing a small decoy peptide to prevent NE-mediated Siglec-G cleavage has emerged as a promising strategy to sustain peritoneal B-1a cell homeostasis, alleviate inflammation, and ultimately improve outcomes in sepsis patients.

Acanthopanacis Cortex (A.-C) with a long history of more than1000 years, has been used to treat rheumatism effectively. Nineteen diterpenoids have been isolated from A.-C, including six new compounds (1-6). Among them, compounds 7, 9-11, 13, and 17 were discovered from A.-C for the first time. The structures of 1-6 were determined by analyzing their NMR data and comparing their experimental and calculated electronic circular dichroism spectra. Moreover, the single-crystal X-ray diffraction data of 1, 2, 8, and 14 were provided. The anti-inflammatory activity of 1-5 and 7-18 on neutrophil elastase, cyclooxygenase-1 (COX-1), and cyclooxygenase-2 (COX-2) has been studied in vitro, and the results showed that 15 had almost no inhibitory effects on COX-1 at 200 μM but a significant activity against COX-2 with an IC50 of 0.73 ± 0.006 μΜ. It indicated that compound 15 can provide valuable information for the design of selective COX-2 inhibitors.

Rationale: Bronchiectasis is characterized by acute exacerbations, but the biological mechanisms underlying these events are poorly characterized. Objectives: To investigate the inflammatory and microbial characteristics of exacerbations of bronchiectasis. Methods: A total of 120 patients with bronchiectasis were enrolled and presented with acute exacerbations within 12 months. Spontaneous sputum samples were obtained during a period of clinical stability and again at exacerbation before receipt of antibiotic treatment. A validated rapid PCR assay for bacteria and viruses was used to classify exacerbations as bacterial, viral, or both. Sputum inflammatory assessments included label-free liquid chromatography-tandem mass spectrometry and measurement of sputum cytokines and neutrophil elastase activity. 16 s rRNA sequencing was used to characterize the microbiome. Measurements and Main Results: Bronchiectasis exacerbations showed profound molecular heterogeneity. At least one bacterium was identified in 103 samples (86%), and a high bacterial load (total bacterial load > 107 copies/g) was observed in 81 patients (68%). Respiratory viruses were identified in 55 (46%) patients, with rhinovirus being the most common virus (31%). PCR testing was more sensitive than culture. No consistent change in the microbiome was observed at exacerbation. Exacerbations were associated with increased neutrophil elastase, proteinase-3, IL-1β, and CXCL8. These markers were particularly associated with bacterial and bacterial plus viral exacerbations. Distinct inflammatory and microbiome profiles were seen between different exacerbation subtypes, including bacterial, viral, and eosinophilic events in both hypothesis-led and hypothesis-free analysis using integrated microbiome and proteomics, demonstrating four subtypes of exacerbation. Conclusions: Bronchiectasis exacerbations are heterogeneous events with contributions from bacteria, viruses, and inflammatory dysregulation.

Anti-inflammatory drugs have become the second-largest class of common drugs after anti-infective drugs in animal clinical care worldwide and are often combined with other drugs to treat fever and viral diseases caused by various factors. In our previous study, a novel serine protease inhibitor-encoding gene (MDSPI16) with improved anti-inflammatory activity was selected from a constructed suppressive subducted hybridization library of housefly larvae. This protein could easily induce an immune response in animals and had a short half-life, which limited its wide application in the clinic. Thus, in this study, mPEG-succinimidyl propionate (mPEG-SPA, Mw = 5 kDa) was used to molecularly modify the MDSPI16 protein, and the modified product mPEG-SPA-MDSPI16, which strongly inhibited elastase production, was purified. It had good stability and safety, low immunogenicity, and a long half-life, and the IC50 for elastase was 86 nM. mPEG-SPA-MDSPI16 effectively inhibited the expression of neutrophil elastase and decreased ROS levels. Moreover, mPEG-SPA-MDSPI16 exerted anti-inflammatory effects by inhibiting activation of the NF-κB signaling pathway and the MAPK signaling pathway in neutrophils. It also exerted therapeutic effects on a lipopolysaccharide (LPS)-induced acute lung injury (ALI) mouse model. In summary, mPEG-SPA-MDSPI16 is a novel anti-inflammatory protein modified with PEG that has the advantages of safety, nontoxicity, improved stability, and strong anti-inflammatory activity in vivo and in vitro and is expected to become an effective anti-inflammatory drug.

Acute lung injury (ALI) is a common and critical respiratory disorder caused by various factors, with viral infection being the leading contributor. Dehydroandrographolide (DAP), a constituent of the Chinese herbal plant Andrographis paniculata, exhibits a range of activities including anti-inflammatory, in vitro antiviral and immune-enhancing effects. This study evaluated the anti-inflammatory effects and pharmacokinetics (PK) profile of DAP in ALI mice induced by intratracheal instillation of Poly(I:C) (PIC). The results showed that oral administration of DAP (10-40 mg/kg) effectively suppressed the increase in lung wet-dry weight ratio, total cells, total protein content, accumulation of immune cells, inflammatory cytokines and neutrophil elastase levels in bronchoalveolar lavage fluid of PIC-treated mice. DAP concentrations, determined by an LC-MS/MS method, in plasma after receiving DAP (20 mg/kg) were unchanged compared to those in normal mice. However, DAP concentrations and relative PK parameters in the lungs were significantly altered in PIC-treated mice, exhibiting a relatively higher maximum concentration, larger AUC, and longer elimination half-life than those in the lungs of normal mice. These results demonstrated that DAP could improve lung edema and inflammation in ALI mice, and suggested that lung injury might influence the PK properties of DAP, leading to increased lung distribution and residence. Our study provides evidence that DAP displays significant anti-inflammatory activity against viral lung injury and is more likely to distribute to damaged lung tissue.

Objective: To explore the clinical characteristics of neutrophil extracellular trap (NET) in patients with severe cerebral venous sinus thrombosis (CVST) and to study their prognostic value in the acute and subacute phases. Methods: This study is a retrospective case series analysis. Clinical and pathological data of 52 patients with severe cerebral venous sinus thrombosis who underwent endovascular treatment in the Department of Neurosurgery, Tianjin Huanhu Hospital from June 2019 to June 2022 were retrospectively analyzed. There were 20 males and 32 females, with an age of (40.1±13.6) years(range:18 to 66 years). Forty-five healthy physical examinees were included in the control group. High-resolution MRI was used to stage the thrombus, with 11 cases in the acute group, 28 cases in the subacute group, and 13 cases in the chronic group. Thrombus specimens were obtained through endovascular treatment, and the fluorescence intensity of NET in peripheral blood at different time points was analyzed by immunofluorescence contrast,including the double-stranded DNA structure and adhesion protein components (citrolinated histone H3 (CitH3), myeloperoxidase-DNA complex(MPO-DNA), neutrophil elastase (NE)). The NET markers were determined by ELISA. Spearman rank correlation analysis was used to analyze the correlation between the NET markers in peripheral blood of patients with severe cerebral venous sinus thrombosis in the acute and subacute phases and the volume of venous sinus thrombus, the degree of venous sinus recanalization after treatment, and the discharge modified Rankin scale(mRS)score. The accuracy of NET markers in predicting the prognosis of patients with severe cerebral venous sinus thrombosis was analyzed by drawing receiver operating characteristic (ROC) curve and calculating the area under the curve (AUC). Results: The results of immunofluorescence staining and ELISA showed that no NET structure was formed in the peripheral blood of the control group, while CitH3, MPO-DNA and NE levels in the peripheral blood of CVST patients were increased, among which the acute stage group was the highest, followed by the subacute group, and the chronic group was the lowest. Spearman correlation analysis showed that CitH3, MPO-DNA and NE levels in peripheral blood of patients in acute group and subacute group were positively correlated with thrombus volume and mRS score at discharge (P<0.05). The levels of CitH3 and MPO-DNA in peripheral blood of patients with complete venous sinus recanalization were lower than those of patients with partial venous sinus recanalization (P<0.01). ROC curve analysis results showed that MPO-DNA and NE had no predictive ability for the prognosis of CVST patients (P values were 0.614 and 0.324, respectively), and the AUC of CitH3 was 0.800 (95%CI: 0.638~0.962, P=0.032), the best cut-off value was 13.5 μg/L, the sensitivity was 100%, and the specificity was 58.8%. Conclusions: A large number of NET are formed in patients with severe cerebral venous sinus thrombosis in acute stage. Patients with severe cerebral venous sinus thrombosis in acute stage and subacute stage with high peripheral blood NET content has a low rate of complete sinus revascularization and poor neurological function recovery after treatment.
目的： 探讨中性粒细胞胞外诱捕网（NET）在重症脑静脉窦血栓（CVST）患者中的临床特征及其对急性期、亚急性期患者的预后价值。 方法： 本研究为回顾性病例系列研究。回顾性分析2019年6月至2022年6月在天津市环湖医院神经外科接受血管内治疗的52例重症CVST患者的临床和病理学资料。男性20例，女性32例，年龄（40.1±13.6）岁（范围：18~66岁）。纳入同期45名健康体检者作为对照组。CVST患者术前均行高分辨MRI对血栓进行分期，根据分期将患者分为急性组（11例）、亚急性组（28例）和慢性组（13例），并经血管内治疗获取血栓标本，经免疫荧光染色对比不同分期患者外周血NET标志物［瓜氨酸化组蛋白H3（CitH3）、髓过氧化物酶-DNA复合物（MPO-DNA）、中性粒细胞弹性蛋白酶（NE）］的荧光强度，并采用ELISA测定患者外周血附着蛋白水平。采用Spearman秩相关分析法分析急性、亚急性组患者外周血中不同NET标志物与静脉窦内血栓体积、治疗后静脉窦再通程度、出院时改良Rankin量表（mRS）评分的相关性；通过绘制受试者工作特征（ROC）曲线并计算曲线下面积（AUC）分析不同NET标志物预测重症脑静脉窦血栓患者预后的准确性。 结果： 免疫荧光染色和ELISA实验结果显示，对照组外周血中未见NET结构形成，CVST患者外周血中CitH3、MPO-DNA、NE水平均升高，其中急性期组最高，亚急性组次之，慢性组最低。Spearman相关分析结果显示，急性组、亚急性组患者外周血CitH3、MPO-DNA、NE水平均与血栓体积及患者出院时mRS评分成正相关（P值均<0.05）。静脉窦完全再通患者外周血CitH3、MPO-DNA水平均低于静脉窦部分再通患者（P值均<0.01）。ROC曲线分析结果显示，MPO-DNA、NE对CVST患者预后无预测能力（P值分别为0.614、0.324），CitH3的AUC为0.800（95%CI：0.638~0.962，P=0.032），最佳截点值为13.5 μg/L，灵敏度为100%，特异度为58.8%。 结论： CVST患者体内有大量的NET形成，外周血NET含量高的急性期、亚急性期重症CVST患者治疗后静脉窦完全再通率低，神经功能恢复差。CitH3水平对急性期、亚急性期重症CVST患者有一定预后价值。.