Iron Overload-Dependent Ferroptosis Aggravates LPS-Induced Acute Lung Injury by Impairing Mitochondrial Function.

Ferroptosis is a newly proposed form of programmed cell death that is iron-dependent and closely linked to oxidative stress. Its specific morphological changes include shrunken mitochondria, increased density of mitochondrial membrane, and rupture or disappearance of mitochondrial cristae. The main mechanism of ferroptosis involves excessive free iron reacting with membrane phospholipids, known as the Fenton reaction, resulting in lipid peroxidation. However, the role of iron in acute lung injury (ALI) remains largely unknown. In this study, LPS was instilled into the airway to induce ALI in mice. We observed a significant increase in iron concentration during ALI, accompanied by elevated levels of lipid peroxidation markers such as malonaldehyde (MDA) and 4-hydroxynonenal (4-HNE). Treatment with the iron chelator deferoxamine (DFO) or ferroptosis inhibitor ferrostatin-1 (Fer-1) reversed lipid peroxidation and significantly attenuates lung injury. Similarly, DFO or Fer-1 treatment improved the cell survival significantly in vitro. These results demonstrated that ferroptosis occurs during ALI and that targeting ferroptosis is an effective treatment strategy. Interestingly, we found that the increased iron was primarily concentrated in mitochondria and DFO treatment effectively restored normal mitochondria morphology. To further confirm the damaging effect of iron on mitochondria, we performed mitochondrial stress tests in vitro, which revealed that iron stimulation led to mitochondrial dysfunction, characterized by impaired basal respiratory capacity, ATP production capacity, and maximum respiratory capacity. MitoTEMPO, an antioxidant targeting mitochondria, exhibited superior efficacy in improving iron-induced mitochondrial dysfunction compared to the broad-spectrum antioxidant NAC. Treatment with MitoTEMPO more effectively alleviated ALI. In conclusion, ferroptosis contributes to the pathogenesis of ALI and aggravates ALI by impairing mitochondrial function.

Quantitative detection of mpox antigen using time-resolved fluorescence immunochromatography.

Recently, concern has been raised about the spread of human mpox virus, and the demand for rapid detection reagents for mpox virus has increased. This study aims to establish a time-resolved fluorescence immunochromatography (TRFICO) method for qualitative/quantitative detection of mpox virus. A double-antibody sandwich TRFICO method was optimized and established using mpox recombinant fusion antigen and its paired monoclonal antibody. The test performance of the method was evaluated using mpox fusion antigen and control serum, including sensitivity, linearity range, specificity, precision, and reference interval. We successfully established a TRFICO method for qualitative/quantitative detection of mpox antigen, its linearity range 0-100 ng/mL, analytical sensitivity 0.017 ng/mL, and reference intervals greater than 0.045 ng/mL. No cross-reaction was detected with various poxvirus and clinical negative controls, with good specificity. All average recoveries of the intra- and inter-batch ranged from 81.33% to 97.83%, and all CVs were below 10%. Additionally, the TRFICO strips can be stably stored at 37°C for 7 days without significant changes in the fluorescence intensity. This TRFICO method, with high sensitivity, linearity range, specificity, precision, and stability with 16-min detection time, provides a new option for qualitative/quantitative and convenient testing of mpox virus.

Plasmonic Alloys Enhanced Metabolic Fingerprints for the Diagnosis of COPD and Exacerbations.

Accurate diagnosis of chronic obstructive pulmonary disease (COPD) and exacerbations by metabolic biomarkers enables individualized treatment. Advanced metabolic detection platforms rely on designed materials. Here, we design mesoporous PdPt alloys to characterize metabolic fingerprints for diagnosing COPD and exacerbations. As a result, the optimized PdPt alloys enable the acquisition of metabolic fingerprints within seconds, requiring only 0.5 µL of native plasma by laser desorption/ionization mass spectrometry owing to the enhanced electric field, photothermal conversion, and photocurrent response. Machine learning decodes metabolic profiles acquired from 431 individuals, achieving a precise diagnosis of COPD with an area under the curve (AUC) of 0.904 and an accurate distinction between stable COPD and acute exacerbations of COPD (AECOPD) with an AUC of 0.951. Notably, eight metabolic biomarkers identified accurately discriminate AECOPD from stable COPD while providing valuable information on disease progress. Our platform will offer an advanced nanoplatform for the management of COPD, complementing standard clinical techniques.

Development of a time-resolved fluorescence immunoassay kit for detecting canine coronavirus and parvovirus through double labeling.

OBJECTIVE: Canine enteric coronavirus (CCV) and canine parvovirus type 2 (CPV-2) are the main pathogens responsible for acute gastroenteritis in dogs, and both single and mixed infections are common. This study aimed to establish a double-labeling time-resolved fluorescence immunoassay (TRFIA) to test and distinguish CCV and CPV-2 diseases. METHODS: A sandwich double-labeling TRFIA method was established and optimized using europium(III) (Eu3+)/samarium(III) (Sm3+) chelates. CCV/CPV-2 antigens were first captured by the immobilized antibodies. Then, combined with Eu3+/Sm3+-labeled paired antibodies, the Eu3+/Sm3+ fluorescence values were detected after dissociation to calculate the CCV/CPV-2 ratios. The performance, clinical performance and methodology used for laboratory (sensitivity, specificity, accuracy and stability) testing were evaluated. RESULTS: A double-label TRFIA for CCV and CPV-2 detection was optimized and established. The sensitivity of this TRFIA kit was 0.51 ng/mL for CCV and 0.80 ng/mL for CPV-2, with high specificity for CCV and CPV-2. All the accuracy data were less than 10%, and the recovery ranged from 101.21 to 110.28%. The kits can be temporarily stored for 20 days at 4 °C and can be stored for 12 months at temperatures less than - 20 °C. Based on a methodology comparison of 137 clinically suspected patients, there was no statistically significant difference between the TRFIA kit and the PCR method. Additionally, for CCV detection, the clinical sensitivity was 95.74%, and the clinical specificity was 93.33%. For CPV-2 detection, the clinical sensitivity was 92.86%, and the clinical specificity was 96.97%. CONCLUSION: In this study, a double-label TRFIA kit was prepared for CCV and CPV-2 detection with high laboratory sensitivity, specificity, accuracy, stability, clinical sensitivity and specificity. This kit provides a new option for screening/distinguishing between CCV and CPV-2 and may help improve strategies to prevent and control animal infectious diseases in the future.

Critical roles of PAI-1 in lipopolysaccharide-induced acute lung injury.

PURPOSE: Plasminogen activator inhibitor-1 (PAI-1) is the main inhibitor of fibrinolytic systems. The effect of PAI-1 on inflammatory response is still inconsistent. Our study was conducted to investigate its effects on inflammation to clarify the role of PAI-1 in acute lung injury (ALI) induced by lipopolysaccharide (LPS). MATERIAL AND METHODS: ALI models were established in wild-type (WT) and PAI-1 knockout (KO) mice by LPS intervention for 48 â€‹h. Lung histopathology, wet-dry ratio, total cell count and TNF-α concentration in bronchoalveolar lavage fluid (BALF), and inflammation related proteins were detected. Flow cytometry was used to sort neutrophils, macrophages, regulatory T cells (Treg) and T helper cell 17 (Th17). RNA sequencing was performed to find differentially expressed genes. Masson staining and immunohistochemistry were used to analyze pulmonary fiber deposition and proliferation. RESULTS: Compared with ALI (WT) group, the wet-dry ratio, the total number of BALF cells, the concentration of TNF-α in BALF, and the expression of pp65 in the lung tissue was increased in ALI (PAI-1 KO) group, with increased proportion of neutrophils, decreased proportion of macrophages and decreased proportion of Treg/Th17 in the lung tissue. Collagen fiber deposition and PCNA expression were lighter in ALI (PAI-1 KO) group than ALI (WT) group. PPI analysis showed that PAI-1 was closely related to TNF, IL-6, IL-1ß, Smad2/3 and mainly concentrated in the complement and coagulation system, TNF-α and IL-17 signaling pathways. CONCLUSIONS: PAI-1 KO could aggravate ALI induced by LPS at 48 â€‹h. PAI-1 may be an important target to improve the prognosis of ALI.

Development of a fluorescence immunochromatography method for quantitative measurement of matrix metalloproteinase-9.

Objective: Abnormal serum matrix metalloproteinase-9 (MMP-9) levels are closely related to the occurrence and development of many diseases. This study aimed to establish a fluorescence immunochromatography (FIC) method using the lanthanide fluorescent element europium(III) (Eu3+) for the quantitative measurement of MMP-9 in serum. Design & Methods: The FIC method for quantifying MMP-9 was optimized and established, and the FIC test strips (FICTS) were assembled and subsequently evaluated for sensitivity, specificity and precision. Furthermore, the reference interval and clinical sensitivity/specificity were estimated using clinical healthy/positive serum samples, and a commercial ELISA was used for comparison. Results: We successfully established an FIC method and prepared FICTS. The analytical sensitivity of the FICTS was 0.92 ng/mL, with a linearity range of 0-1000 ng/mL. The cross-reactivity of the 7 common serum interferents was less than 1.56%. All recoveries of the intra-array and inter-array samples ranged from 102.50% to 110.99%, and all CVs were less than 5%. The reference interval of the FICTS was >161.15 ng/mL. The clinical sensitivity was 96.00%, and the specificity was 97.5%. The results of 270 clinical serum samples were highly coincident with the clinical diagnostic results. Pearson correlation analysis and Bland‒Altman plots indicated that the FICTS and commercial ELISA results were consistent with the quantitative MMP-9 concentration. Conclusions: The designed FIC method and test strips may be suitable for point-of-care quantitative measurement of MMP-9, which provides a new method for screening for atherosclerosis, xerophthalmia, etc.

Regulator of G protein signaling protein 6 alleviates acute lung injury by inhibiting inflammation and promoting cell self-renewal in mice.

BACKGROUND: Acute respiratory distress syndrome (ARDS) is a disease with high mortality and morbidity. Regulator of G protein signaling protein 6 (RGS6), identified as a tumor suppressor gene, has received increasing attention owing to its close relationship with oxidative stress and inflammation. However, the association between ARDS and RGS6 has not been reported. METHODS: Congruously regulated G protein-coupled receptor (GPCR)-related genes and differentially expressed genes (DEGs) in an acute lung injury (ALI) model were identified, and functional enrichment analysis was conducted. In an in vivo study, the effects of RGS6 knockout were studied in a mouse model of ALI induced by lipopolysaccharide (LPS). HE staining, ELISA, and immunohistochemistry were used to evaluate pathological changes and the degree of inflammation. In vitro, qRT‒PCR, immunofluorescence staining, and western blotting were used to determine the dynamic changes in RGS6 expression in cells. The RGS6 overexpression plasmid was constructed for transfection. qRT‒PCR was used to assess proinflammatory factors transcription. Western blotting and flow cytometry were used to evaluate apoptosis and reactive oxygen species (ROS) production. Organoid culture was used to assess the stemness and self-renewal capacity of alveolar epithelial type II cells (AEC2s). RESULTS: A total of 110 congruously regulated genes (61 congruously upregulated and 49 congruously downregulated genes) were identified among GPCR-related genes and DEGs in the ALI model. RGS6 was downregulated in vivo and in vitro in the ALI model. RGS6 was expressed in the cytoplasm and accumulated in the nucleus after LPS stimulation. Compared with the control group, we found higher mortality, more pronounced body weight changes, more serious pulmonary edema and pathological damage, and more neutrophil infiltration in the RGS6 knockout group upon LPS stimulation in vivo. Moreover, AEC2s loss was significantly increased upon RGS6 knockout. Organoid culture assays showed slower alveolar organoid formation, fewer alveolar organoids, and impaired development of new structures after passaging upon RGS6 knockout. In addition, RGS6 overexpression decreased ROS production as well as proinflammatory factor transcription in macrophages and decreased apoptosis in epithelial cells. CONCLUSIONS: RGS6 plays a protective role in ALI not only in early inflammatory responses but also in endogenous lung stem cell regeneration.

Prevalence of the virulence genes and their correlation with carbapenem resistance amongst the Pseudomonas aeruginosa strains isolated from a tertiary hospital in China.

Pseudomonas aeruginosa is one of the top-listed pathogens in nosocomial infection. It is notorious for its complicated virulence system and rapid adaptability to drugs or antimicrobials. In this study, we aimed to evaluate the prevalence of sixteen virulence genes in four groups including type III secretion system, biofilm formation, extracellular toxin biosynthesis and enzymes amongst 209 clinical Pseudomonas aeruginosa strains. We investigated the different distribution patterns of virulence genotypes based on carbapenem-resistant phenotype or the carriage of carbapenemase genes. The detection rate of each virulence gene varied greatly. phzM and plcN were detected in all collected strains, while pilB and exoU were only carried by a small portion of isolates (6.7% and 16.3%). Additionally, the number of genotypes observed in each group of examined virulence genes ranged from 4 to 8. Only the distribution of genotypes of type III secretion system showed statistical difference between carbapenem-mediated or carbapenem-resistant and carbapenem-sensitive strains. The virulence genotype of Pseudomonas aeruginosa was possibly interrelated to its resistance mechanism. Further research suggested that one particular TTSS genotype exhibited higher ratio in carbapenemase-producing strains and exoS was less frequently detected in CRPA strains carrying carbapenemase gene. Generally, the significant genetic diversity of virulence genes amongst Pseudomonas aeruginosa strains was highlighted in this study. Specific TTSS genotypes were associated with carbapenem-resistance. In particular, certain incompatibility might exist between exoS and carbapenemase genes, which provided valuable information for further understanding the relationship between carbapenem resistance and virulence.

Xuebijing alleviates LPS-induced acute lung injury by downregulating pro-inflammatory cytokine production and inhibiting gasdermin-E-mediated pyroptosis of alveolar epithelial cells.

Acute lung injury/acute respiratory distress syndrome (ALI/ARDS) is characterized by diffuse alveolar injury primarily caused by an excessive inflammatory response. Regrettably, the lack of effective pharmacotherapy currently available contributes to the high mortality rate in patients with this condition. Xuebijing (XBJ), a traditional Chinese medicine recognized for its potent anti-inflammatory properties, exhibits promise as a potential therapeutic agent for ALI/ARDS. This study aimed to explore the preventive effects of XBJ on ALI and its underlying mechanism. To this end, we established an LPS-induced ALI model and treated ALI mice with XBJ. Our results demonstrated that pre-treatment with XBJ significantly alleviated lung inflammation and increased the survival rate of ALI mice by 37.5%. Moreover, XBJ substantially suppressed the production of TNF-α, IL-6, and IL-1ß in the lung tissue. Subsequently, we performed a network pharmacology analysis and identified identified 109 potential target genes of XBJ that were mainly involved in multiple signaling pathways related to programmed cell death and anti-inflammatory responses. Furthermore, we found that XBJ exerted its inhibitory effect on gasdermin-E-mediated pyroptosis of lung cells by suppressing TNF-α production. Therefore, this study not only establishes the preventive efficacy of XBJ in ALI but also reveals its role in protecting alveolar epithelial cells against gasdermin-E-mediated pyroptosis by reducing TNF-α release.

Determination of serum CA724 levels using fluorescence immunochromatography.

BACKGROUND: Carbohydrate antigen 724 (CA724) is a sensitive and specific indicator for multiple malignant tumors. The aim of this study was to establish a Eu-time resolved fluorescence immunochromatography (Eu-TRFICO) method for quantitative detection of CA724 in serum. METHODS: Eu-TRFICO strips were optimized and assembled. The sensitivity, specificity and precision were evaluated using CA724 standard dilutions and matrix serum. Meanwhile, the reference interval, comparison, and sensitivity/specificity were performed using clinical negative/positive gastric cancer serum samples. RESULTS: The standard curve equation was y = 9.869 x - 154.12 (R2 = 0.993), and the sensitivity was 0.42 U/mL. The common interferents in serum could not affect the quantitative results with low cross-reactivities (all no more than 1.09%). All average recoveries of the intra- and interbatch ranged from 102.38 to 106.40%, and all CVs were below 10%. The reference interval of the healthy subjects was < 4.68 U/mL and the reference interval of the subjects with grade I/II gastric cancer was > 9.54 U/mL. Additionally, a high Pearson r (0.9503) and sensitivity/specificity (92.86%/94.20%) were obtained. CONCLUSION: This study prepared Eu-TRFICO strips with high sensitivity, specificity, precision and satisfactory clinical testing performance, which provides more options for clinical quantitative and convenient testing of CA724.

α7nAChR activation in AT2 cells promotes alveolar regeneration through WNT7B signaling in acute lung injury.

Reducing inflammatory damage and improving alveolar epithelium regeneration are two key approaches to promoting lung repair in acute lung injury/acute respiratory distress syndrome (ALI/ARDS). Stimulation of cholinergic α7 nicotinic acetylcholine receptor (α7nAChR, coded by Chrna7) signaling could dampen lung inflammatory injury. However, whether activation of α7nAChR in alveolar type II (AT2) cells promotes alveolar epithelial injury repair and underlying mechanisms is elusive. Here, we found that α7nAChR was expressed on AT2 cells and was upregulated in response to LPS-induced ALI. Meanwhile, deletion of Chrna7 in AT2 cells impeded lung repair process and worsened lung inflammation in ALI. Using in vivo AT2 lineage-labeled mice and ex vivo AT2 cell-derived alveolar organoids, we demonstrated that activation of α7nAChR expressed on AT2 cells improved alveolar regeneration by promoting AT2 cells to proliferate and subsequently differentiate toward alveolar type I cells. Then, we screened out the WNT7B signaling pathway by the RNA-Seq analysis of in vivo AT2 lineage-labeled cells and further confirmed its indispensability for α7nAChR activation-mediated alveolar epithelial proliferation and differentiation. Thus, we have identified a potentially unrecognized pathway in which cholinergic α7nAChR signaling determines alveolar regeneration and repair, which might provide us a novel therapeutic target for combating ALI.

Determination of echinococcosis IgG antibodies using magnetic bead-based chemiluminescence immunoassay.

Echinococcosis is a kind of parasitic disease shared by humans and animals. The aim of this study was to establish a new detection method for echinococcosis screening using magnetic bead-based chemiluminescence immunoassay (CLIA). A magnetic bead-based CLIA to determine anti-echinococcosis IgG antibodies was optimized and established. The sensitivity, accuracy, precision and recovery rate were evaluated using the national reference serum, and the reference interval, specificity and comparison assays were performed using the clinical negative/positive echinococcosis serum samples. This study established a new CLIA to determine anti-echinococcosis IgG antibodies. The sensitivity of this CLIA method was higher than that of the registered ELISA kit and the national standard, the conformance rate of the negative/positive references was 100% (8/8), the CVs of the sensitivity reference were all below 5%, and the CVs of the precision reference were 5.7%. There was no obvious cross-reactivity with the common parasitic disease-positive serum and serum interferents. Clinical sample testing found that the cutoff value of this CLIA was 5537.15 (RLU), and there was no significant difference between the CLIA method and the registered ELISA kit. This study established a fully automated CLIA method with high sensitivity, specificity, accuracy, precision, recovery rate, and satisfactory clinical testing performance, which may provide a new choice for echinococcosis screening.

Associations between short-term exposure to ambient air pollution and lung function in adults.

BACKGROUND: Evidence of the acute effects of high-level air pollution on small airway function and systemic inflammation in adults is scarce. OBJECTIVE: To examined the associations of short-term (i.e., daily) exposure to multiple air pollutants with lung function and inflammatory markers. METHODS: We assessed short-term (daily) effects of air pollutants, including particulate matter with aerodynamic diameter less than 2.5 µm (PM2.5) and 10 µm (PM10), nitrogen dioxide (NO2), sulfur dioxide (SO2) and carbon monoxide (CO), on lung function and peripheral immune cell counts over various lag times using generalized linear regression models. RESULTS: A total of 4764 adults were included from the general community-dwelling population in Shanghai, China. Exposure to air pollutants and lung function were negatively correlated. Decline in FEF between 25% and 75% of vital capacity (FEF25-75%) were found associated with PM2.5, SO2, and CO, and decline in forced expiratory volume in 3 s (FEV3) to forced vital capacity (FVC) ratio were associated with all examined pollutants, indicating obstruction in small airways. Obstructed airflow in large and middle airways as indicated by decline in FEV1/FVC were also associated with all pollutants. In subgroup analysis, significant negative associations between the five pollutants and SAD parameters were found only in males but not in females. The difference in the associations of SO2 with FEF75% between males and females achieved statistical significance. Additionally, all examined pollutants were significantly associated with lower peripheral neutrophil count. IMPACT STATEMENT: Acute exposure to air pollutants were associated with airflow-limitation. Both small airways and proximal airways were affected. Acute exposure to air pollutants were accompanied with a lower neutrophil count.

Perturbation of arachidonic acid and glycerolipid metabolism promoted particulate matter-induced inflammatory responses in human bronchial epithelial cells.

Particulate matter (PM) has become the main risk factor for public health, being linked with an increased risk of respiratory diseases. However, the potential mechanisms underlying PM-induced lung injury have not been well elucidated. In this study, we systematically integrated the metabolomics, lipidomics, and transcriptomics data obtained from the human bronchial epithelial cells (HBECs) exposed to PM to reveal metabolic disorders in PM-induced lung injury. We identified 170 differentially expressed metabolites (82 upregulated and 88 downregulated metabolites), 218 differentially expressed lipid metabolites (125 upregulated and 93 downregulated lipid metabolites), and 1417 differentially expressed genes (643 upregulated and 774 downregulated genes). Seven key metabolites (prostaglandin E2, inosinic acid, L-arginine, L-citrulline, L-leucine, adenosine, and adenosine monophosphate), and two main lipid subclasses (triglyceride and phosphatidylcholine) were identified in PM-exposed HBECs. The amino acid metabolism, lipid metabolism, and carbohydrate metabolism were the significantly enriched pathways of identified differentially expressed genes. Then, conjoint analysis of these three omics data and further qRT-PCR validation showed that arachidonic acid metabolism, glycerolipid metabolism, and glutathione metabolism were the key metabolic pathways in PM-exposed HBECs. The knockout of AKR1C3 in arachidonic acid metabolism or GPAT3 in glycerolipid metabolism could significantly inhibit PM-induced inflammatory responses in HBECs. These results revealed the potential metabolic pathways in PM-exposed HBECs and provided a new target to protect from PM-induced airway damage.

The prediction of lymphocyte count and neutrophil count on the efficacy of Xuebijing adjuvant treatment for severe community-acquired pneumonia: A post hoc analysis of a randomized controlled trial.

BACKGROUND: Adjuvant Xuebijing therapy exhibited a protective effect on severe community-acquired pneumonia (SCAP) in previous studies. Blood inflammatory biomarkers related to the disease subtype and severity of SCAP might be associated with the effects of Xuebijing on clinical outcomes of SCAP. PURPOSE: To investigate whether neutrophils or lymphocytes are a useful biomarker of the therapeutic effect of Xuebijing on mortality and inflammation damage index. STUDY DESIGN: A post hoc analysis of a randomized, placebo-controlled and double-blinded clinical trial of Xuebijing in patients with SCAP (Clinical Trial Registration: ChiCTR-TRC-13003534). METHODS: We compared 28-day mortality (primary outcome) and four clinical scores (secondary outcome), including pneumonia severity index (PSI) score, sequential organ failure assessment (SOFA) score, acute physiology and chronic health evaluation II (APACHE II) score, and systemic inflammatory response syndrome (SIRS) score, according to the baseline strata of neutrophil count and lymphocyte count. RESULTS: A total of 675 patients were included in the analyses, of which 334 received Xuebijing and 341 received the placebo. Xuebijing was more effective in SCAP patients with higher lymphocyte counts and lower neutrophil counts. In the lymphocyte-dominated inflammation (LDI) subgroup, defined as neutrophil count <13 × 109 cells/l and lymphocyte count ≥0.65 × 109 cells/l, Xuebijing reduced 28-day mortality by 15% while mortality of the neutrophil-dominated inflammation (NDI) subgroup decreased by 4.7% (p = 0.050). There was also greater improvement in the PSI, SOFA, APACHE II, and SIRS scores following Xuebijing treatment in the LDI subgroup compared with the NDI subgroup. CONCLUSIONS: Xuebijing treatment shows stronger protective effects in SCAP patients with higher lymphocyte and lower neutrophil counts. Our findings may facilitate the selection of the most appropriate treatments for individual patients with SCAP, including who will receive Xuebijing injections.

Tumor mutational burden and efficacy of chemotherapy in lung cancer

Purpose TMB is one of the potent biomarkers of response to immune checkpoint blockade. The association between TMB and efficacy of chemotherapy in advanced lung cancer has not been comprehensively explored. Methods Ninety lung cancer patients receiving first-line chemotherapy with large panel next-generation sequencing data of pre-treatment tumor tissue were identified. The effect of TMB on PFS of chemotherapy were evaluated in univariate and multivariate analyses. Results The median TMB level of lung cancer patients enrolled in this study was 9.4 mutations/Mb, with TMB levels in smokers significantly higher than those in non-smokers. All patients were divided into high TMB and low TMB groups with the cutoff of the median TMB. The patients with low TMB had longer PFS of first-line chemotherapy (median PFS 9.77 vs 6.33 months, HR = 0.523, 95% CI 0.32–0.852, log-rank P = 0.009). Subgroup analysis showed that PFS of chemotherapy favored low TMB than high TMB among subgroups of male, age < 60, NSCLC, adenocarcinoma, stage IV, ECOG PS 0, driver mutation positive, TP53 wild type and patients not receiving bevacizumab. In multivariate analysis, PFS of chemotherapy remained significantly longer in low TMB group (HR = 0.554, p = 0.036). In those patients received immunotherapy upon unsatisfactory chemotherapy, PFS of immunotherapy was much longer in high TMB group (median PFS 32.88 vs 6.62 months, HR = 0.2426, 95% CI 0.06–0.977, log-rank P = 0.04). Conclusions TMB level of tumor tissue is a potent biomarker for efficacy of chemotherapy and immunotherapy in lung cancer. It may provide some clues for the decision of treatment strategy (AU)

Tumor mutational burden and efficacy of chemotherapy in lung cancer.

PURPOSE: TMB is one of the potent biomarkers of response to immune checkpoint blockade. The association between TMB and efficacy of chemotherapy in advanced lung cancer has not been comprehensively explored. METHODS: Ninety lung cancer patients receiving first-line chemotherapy with large panel next-generation sequencing data of pre-treatment tumor tissue were identified. The effect of TMB on PFS of chemotherapy were evaluated in univariate and multivariate analyses. RESULTS: The median TMB level of lung cancer patients enrolled in this study was 9.4 mutations/Mb, with TMB levels in smokers significantly higher than those in non-smokers. All patients were divided into high TMB and low TMB groups with the cutoff of the median TMB. The patients with low TMB had longer PFS of first-line chemotherapy (median PFS 9.77 vs 6.33 months, HR = 0.523, 95% CI 0.32-0.852, log-rank P = 0.009). Subgroup analysis showed that PFS of chemotherapy favored low TMB than high TMB among subgroups of male, age < 60, NSCLC, adenocarcinoma, stage IV, ECOG PS 0, driver mutation positive, TP53 wild type and patients not receiving bevacizumab. In multivariate analysis, PFS of chemotherapy remained significantly longer in low TMB group (HR = 0.554, p = 0.036). In those patients received immunotherapy upon unsatisfactory chemotherapy, PFS of immunotherapy was much longer in high TMB group (median PFS 32.88 vs 6.62 months, HR = 0.2426, 95% CI 0.06-0.977, log-rank P = 0.04). CONCLUSIONS: TMB level of tumor tissue is a potent biomarker for efficacy of chemotherapy and immunotherapy in lung cancer. It may provide some clues for the decision of treatment strategy.

Evaluation of a multiplex PCR kit for detection of 17 respiratory pathogens in hospitalized patients.

Background: Rapid pathogen identification is critical for optimizing diagnosis and treatment of infectious diseases. Multiplex polymerase chain reaction (PCR) is a sensitive, broad-spectrum molecular detection technique that is simple and rapid to perform. It is capable of simultaneously screening for multiple pathogens within a short time range. Here, we designed and evaluated a multiplex PCR kit for the identification of 17 common respiratory pathogens in clinical samples from hospitalized patients. Methods: A total of 452 samples from hospitalized patients, including 242 respiratory and 210 non-respiratory samples, were analyzed for 13 bacteria and 4 fungi by a multiplex fluorescent PCR kit. The diagnostic performance of the kit was assessed by considering routine microbiology as the reference standard. Results: The overall positivity rate of the multiplex PCR kit was 86.9%, much higher than that noted on routine microbiology (56.9%). Furthermore, the co-infection detection rate was also significantly higher than that noted on routine microbiology (69.5% vs. 15.0%). Compared with routine microbiology, kit sensitivity was >90% for detection of most target bacteria, with a negative predictive value (NPV) of >99%, especially for detection of Pseudomonas aeruginosa, Klebsiella pneumoniae, Acinetobacter baumannii, Stenotrophomonas maltophilia, Enterococcus faecium, Enterococcus faecalis and Escherichia coli. The kit was noted to be particularly superior in identifying Stenotrophomonas maltophilia and Streptococcus pneumoniae as compared to routine microbiology. The multiplex PCR kit was noted to be less sensitive (33.3-59.6%) and more specific (93.9-100.0%) for detection of mycobacteria and fungi. Conclusions: Our multiplex PCR kit offers a rapid and sensitive diagnosis of common bacterial pneumonia, although sensitivity for mycobacteria and fungi warrants enhancement. Further optimization includes minimizing false positivity and increasing relevance to clinical application.

The evaluation of next-generation sequencing assisted pathogenic detection in immunocompromised hosts with pulmonary infection: A retrospective study.

INTRODUCTION: Pulmonary infections are frequent in immunocompromised hosts (ICH), and microbial detection is difficult. As a new method, next-generation sequencing (NGS) may offer a solution. OBJECTIVES: This study aimed to assess the impact of NGS-assisted pathogenic detection on the diagnosis, treatment, and outcomes of ICH complicated by pulmonary infection and radiographic evidence of bilateral diffuse lesions. METHODS: This study enrolled 356 patients with ICH complicated by pulmonary infection that were admitted to Zhongshan Hospital, Fudan University, from November 17, 2017, to November 23, 2018, including 102 and 254 in the NGS and non-NGS groups, respectively. Clinical characteristics, detection time, rough positive rate, effective positive rate, impact on anti-infective treatment plan, 30-day/60-day mortality, and in-hospital mortality were compared. RESULTS: NGS-assisted pathogenic detection reduced detection time (28.2 h [interquartile range (IQR) 25.9-29.83 h] vs. 50.50 h [IQR 47.90-90.91 h], P < 0.001), increased positive rate, rate of mixed infection detected, effective positive rate, and proportion of antibiotic treatment modification (45.28% vs. 89.22%, 4.72% vs. 51.96%, 21.65% vs. 64.71%, 16.54% vs. 46.08%, P < 0.001). The NGS group had a significantly lower 60-day mortality rate (18.63% vs. 33.07%, P = 0.007). The difference in the Kaplan-Meier survival curve was significant (P = 0.029). After multivariate logistic regression, NGS-assisted pathogenic detection remained a significant predictor of survival (OR 0.189, confidence interval [CI], 0.068-0.526). CONCLUSION: NGS-assisted pathogenic detection may improve detection efficiency and is associated with better clinical outcomes in these patients.

Challenges of vaccination and herd immunity in COVID-19 and management strategies.

Coronavirus disease 2019 (COVID-19), the highly contagious viral disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has spread worldwide with millions of cases and more than 5 million deaths to date. SARS-CoV-2 has caused serious damage all over the world with many countries experiencing the third or the fourth wave of the viral disease outbreaks, mainly due to the emergence of mutant variants. Those who unvaccinated remain most vulnerable to COVID-19 and its variants. COVID-19 vaccination, along with prevention strategies, is a critical measure to defense against the disease. COVID-19 vaccination can reduce the spread of virus and help protect susceptible population. Although herd immunity might not be realized solely by vaccination, COVID-19 vaccines have been proved to be effective in reducing the risk of severe disease, hospitalization, and even death. It is recommended that people get vaccinated as soon as they are eligible. This review summarizes the recent SARS-CoV-2 variants that brought challenges for vaccination and herd immunity and discusses promising management strategies.