Acute severe exacerbation of chronic obstructive pulmonary disease (COPD) is related to high mortality; however, a robust blood biomarker for COPD exacerbation has not been established. Impaired clearance of apoptotic cells is a possible pathogenesis of COPD development. We evaluated the clinical utility of serum cell viability as a predictive biomarker for COPD exacerbation.Using serum from patients with stable COPD, cell viability was analyzed with a lactate dehydrogenase (LDH) assay. The patients were divided into low (optical density [OD] > 0.737) and high (OD ≤ 0.737) cell viability groups. Poisson regression analyses estimated the prognostic impact for COPD exacerbation, and a Cox proportional hazard model determined the impact on mortality. Among 162 patients, 47 were excluded due to follow-up loss within 1 year, asthma or combined interstitial lung disease diagnosis, and unsuitable cell viability measurements. The median follow-up duration was 6.3 years (range 0.7–11 years); 61 (53%) patients experienced at least one moderate or severe exacerbation, and 21 (19.7%) died. Patients in the low cell viability group were older, more likely to have poor quality of life and had a lower proportion of the non-exacerbator phenotype than those in the high cell viability group. The low cell viability group had a higher risk of moderate (incidence rate ratio [IRR], 1.58; p = 0.049) and severe (IRR, 2.69; p = 0.001) exacerbations and mortality (adjusted hazard ratio, 5.79; p = 0.016).We identified that low cell viability, measured with a serum LDH cytotoxicity assay, was associated with severe COPD exacerbation and higher mortality in patients with COPD.

Endotracheal suctioning is an essential but labor-intensive procedure, with the risk of serious complications. A brand new automatic closed-suction device was developed to alleviate the workload of healthcare providers and minimize those complications. We evaluated the clinical efficacy and safety of the automatic suction system in mechanically ventilated patients with pneumonia. In this multicenter, randomized, non-inferiority, investigator-initiated trial, mechanically ventilated patients with pneumonia were randomized to the automatic device (intervention) or conventional manual suctioning (control). The primary efficacy outcome was the change in the modified clinical pulmonary infection score (CPIS) in 3 days. Secondary outcomes were the frequency of additional suctioning and the amount of secretion. Safety outcomes included adverse events or complications. A total of 54 participants, less than the pre-determined number of 102, were enrolled. There was no significant difference in the change in the CPIS over 72 h (−0.13 ± 1.58 in the intervention group, −0.58 ± 1.18 in the control group, p = 0.866), but the non-inferiority margin was not satisfied. There were no significant differences in the secondary outcomes and safety outcomes, with a tendency for more patients with improved tracheal mucosal injury in the intervention group. The novel automatic closed-suction system showed comparable efficacy and safety compared with conventional manual suctioning in mechanically ventilated patients with pneumonia.

Introduction: In 2022 a Lancet commission published Etiotype for chronic obstructive pulmonary disease (COPD). They suggested that pulmonary infection is cause of COPD and among them, tuberculosis (TB) has a strong association with development of COPD in non-smoking patients. According to retrospective study, from 1.7% to 15.4% of patients with COPD reported a prior history of TB. However, those studies had difficulty demonstrating causality in the absence of pre-TB and post-TB spirometry, and potential misclassification of TB exposure due to self-reported methods. Therefore, in this study, we aimed to demonstrate how many patients developed COPD among patients who had been treated for TB for more than 6 months and had lung function before anti-TB treatment. Methods: A multicenter retrospective study was conducted at four South Korean hospital from January 1st 2003 to December 31 2023. Patients who had been treated with anti-TB medication over 6months and had pre-TB and post-TB spirometry were enrolled. Primary end-point was the development of COPD. Secondary end-points included the characteristics of patients who develop COPD. Results: Among the 10,965 TB patients, 7,202 and 2,833 patients were excluded because there was no pre-TB spirometry and post-TB spirometry, respectively. 102 (13.6%) developed COPD. COPD development was strongly correlated with smoking history, socio economic status (SES), severity of TB sequlae. Conclusion: In our study, we found that all TB patients didn't progress to COPD. The factors which associated with development of COPD were heavy smoking history, low SES, and severe tuberculosis sequelae.

Significance Macrophages play a crucial role in chronic inflammatory diseases, such as nonalcoholic steatohepatitis (NASH) and inflammatory bowel disease, but how the proinflammatory function of macrophages is controlled is not well understood. In this work, we identified TBK1 as a pivotal anti-inflammatory factor in macrophages that restricts inflammation in different disease models. Myeloid cell–specific TBK1 deficiency causes spontaneous development of metabolic disorders in aged mice and exacerbates high-fat diet–induced fatty liver disease with NASH-like symptoms. The Tbk1 -MKO mice are also hypersensitive to experimental colitis. We obtained genetic evidence that TBK1 is crucial for controlling proinflammatory signaling pathway in macrophages. These findings establish TBK1 as a pivotal anti-inflammatory factor and a potential therapeutic target for the treatment of inflammatory diseases.

Background Solid tumors harbor mutations that can give rise to neoantigens recognized by T-cell receptors (TCRs) expressed on tumor infiltrating lymphocytes (TILs). We have developed a library of TCR-T cells targeting hotspot mutations based on the non-viral Sleeping Beauty transposon/transposase system, which is presently being evaluated in a first-in-human phase 1/2 study in patients with non-small cell lung, colorectal, endometrial, pancreatic, ovarian, and bile duct cancers. Current methods of TCR discovery require large volume blood draws or immortalization of primary cells with live viruses to make antigen presenting cells (APCs), limiting the ability to efficiently discover new TCRs and is only applicable to some patients. We developed hunTR™ (human neoantigen T-cell Receptor), a rapid, hyperplex platform for the discovery of neoantigen-reactive TCRs from limited starting material. Methods TILs sorted from dissociated tumor specimens were processed to obtain TCR sequences and gene expression profiles on a single cell basis. These data were fed into a novel bioinformatics pipeline that identifies TCRs with predicted neoantigen reactivity. TCRs were reconstructed in Sleeping Beauty transposon plasmids and expressed in TCR cells, an engineered cell line capable of detecting TCR reactivity to both class I and class II HLA-restricted neoepitopes. Somatic single nucleotide variants, short insertions/deletions, and germline class I and II HLA alleles were called for each patient. neoAPCs were engineered to express relevant patient-derived neoantigens and HLA molecules. TCR cells were cocultured with a matrix of neoAPCs, and conditions yielding a neoantigen reactivity were identified. Results A total of 3.1x105 TCR+HLA+neoantigen combinations were evaluated in seven patients with a mean plexity of 4.4x104 per patient. All specimens screened (colorectal n=3, endometrial n=2, breast n=2) yielded at least one neoantigen-reactive TCR. The 57 neoantigen-reactive TCRs (19% of 304 total TCRs screened) identified targeted 20 mutations, including one shared KRAS and 19 personal mutations. Of these, 81% were restricted by HLA class II while 19% were restricted by class I. A median reactive hit rate of 14% was achieved per patient (range 5-31%) with an average of three unique neoantigen specificities (range 1-6). Conclusions In conclusion, hunTR is a hyperplex screening platform that identifies neoantigen-reactive TCRs. hunTR allows for the expansion of our hotspot mutation-targeted TCR library, increasing the addressable population of solid tumor patients (with matching hotspot mutation and HLA allele) eligible for TCR-T cell treatment. In addition, hunTR is applicable for personalized TCR-T therapy such that most solid tumor patients could be eligible for mutation-targeted cell therapy. Ethics Approval Human-derived specimens were obtained through a commercial source that adheres to all applicable regulations and guidelines of the relevant countries including the US.

Abstract Background Despite the high disease burden of chronic obstructive pulmonary disease (COPD) and risk of acute COPD exacerbation, few COPD biomarkers are available. As developmental endothelial locus-1 (DEL-1) has been proposed to possess beneficial effects, including anti-inflammatory effects, we hypothesized that DEL-1 could be a blood biomarker for COPD. Objective To elucidate the role of plasma DEL-1 as a biomarker of COPD in terms of pathogenesis and for predicting acute exacerbation. Methods Cigarette smoke extract (CSE) or saline was intratracheally administered to wild-type (WT) and DEL-1 knockout (KO) C57BL/6 mice. Subsequently, lung sections were obtained to quantify the degree of emphysema using the mean linear intercept (MLI). Additionally, plasma DEL-1 levels were compared between COPD and non-COPD participants recruited in ongoing prospective cohorts. Using negative binomial regression analysis, the association between the plasma DEL-1 level and subsequent acute exacerbation risk was evaluated in patients with COPD. Results In the in vivo study, DEL-1 KO induced emphysema (KO saline vs. WT saline; P = 0.003) and augmented CSE-induced emphysema (KO CSE vs. WT CSE; P < 0.001) in 29 mice. Among 537 participants, patients with COPD presented plasma log (DEL-1) levels lower than non-COPD participants (P = 0.04), especially non-COPD never smokers (P = 0.019). During 1.2 ± 0.3 years, patients with COPD in the lowest quartile of Log(DEL-1) demonstrated an increased risk of subsequent acute exacerbation, compared with those in the highest quartile of Log(DEL-1) (adjusted incidence rate ratio, 3.64; 95% confidence interval, 1.03–12.9). Conclusion Low DEL-1 levels are associated with COPD development and increased risk of subsequent COPD acute exacerbation. DEL-1 can be a useful biomarker in patients with COPD.

Receptor-interacting protein kinase-1 (RIPK1) is a master regulator of the TNF-α-induced cell death program. The function of RIPK1 is tightly controlled by posttranslational modifications, including linear ubiquitin chain assembly complex-mediated linear ubiquitination. However, the physiological function and molecular mechanism by which linear ubiquitination of RIPK1 regulates TNF-α-induced intracellular signaling remain unclear. In this article, we identified Lys627 residue as a major linear ubiquitination site in human RIPK1 (or Lys612 in murine RIPK1) and generated Ripk1K612R/K612R mice, which spontaneously develop systemic inflammation triggered by sustained emergency hematopoiesis. Mechanistically, without affecting NF-κB activation, Ripk1K612R/K612R mutation enhances apoptosis and necroptosis activation and promotes TNF-α-induced cell death. The systemic inflammation and hematopoietic disorders in Ripk1K612R/K612R mice are completely abolished by deleting TNF receptor 1 or both RIPK3 and Caspase-8. These data suggest the critical role of TNF-α-induced cell death in the resulting phenotype in Ripk1K612R/K612R mice. Together, our results demonstrate that linear ubiquitination of RIPK1 on K612 is essential for limiting TNF-α-induced cell death to further prevent systemic inflammation.

Background/Aims We assessed the diagnostic yield of chest computed tomography (CT) as an initial diagnostic method for patients with a tuberculosis (TB) infection detected by mass screening in a country with an intermediate TB burden. Methods A retrospective study was conducted on patients with TB infection detected by mass screening performed between January 2015 and March 2018. The patients were classified according to whether they had a chest X-ray (CXR) or CT scan as an initial diagnostic test to exclude active TB. Results Of 542 patients with TB infection detected by mass screening, 222 and 320 were initially examined by CXR and CT, respectively; the two modalities showed no significant difference in rate of detection of patients with active TB (0.9% and 2.5%, respectively; p = 0.110). However, chest CT was associated with further invasive tests using bronchoscopy and respiratory specimens, and significantly increased the frequency of hospital visits. Conclusions Chest CT was not supported as an initial diagnostic method to rule out active TB in patients with a TB infection detected by mass screening in a country with an intermediate TB burden.

The linear ubiquitin chain assembly complex (LUBAC) regulates NF-κB activation by modifying proteins with linear (M1-linked) ubiquitination chains. Although LUBAC also regulates the apoptosis pathway, the precise mechanism by which LUBAC regulates apoptosis remains not fully defined. Here, we report that LUBAC-mediated M1-linked ubiquitination of cellular FLICE-like inhibitory protein (cFLIP), an anti-apoptotic molecule, contributes to tumor necrosis factor (TNF) α-induced apoptosis. We found that deficiency of RNF31, the catalytic subunit of the LUBAC complex, promoted cFLIP degradation in a proteasome-dependent manner. Moreover, we observed RNF31 directly interact with cFLIP, and LUBAC further conjugated M1-linked ubiquitination chains at Lys-351 and Lys-353 of cFLIP to stabilize cFLIP, thereby protecting cells from TNFα-induced apoptosis. Together, our study identifies a new substrate of LUBAC and reveals a new molecular mechanism through which LUBAC regulates TNFα-induced apoptosis via M1-linked ubiquitination.

Dendritic cells (DCs) play an integral role in regulating mucosal immunity and homeostasis, but the signaling network mediating this function of DCs is poorly defined. We identified the noncanonical NF-κB-inducing kinase (NIK) as a crucial mediator of mucosal DC function. DC-specific NIK deletion impaired intestinal immunoglobulin A (IgA) secretion and microbiota homeostasis, rendering mice sensitive to an intestinal pathogen, Citrobacter rodentium. DC-specific NIK was required for expression of the IgA transporter polymeric immunoglobulin receptor (pIgR) in intestinal epithelial cells, which in turn relied on the cytokine IL-17 produced by T H 17 cells and innate lymphoid cells (ILCs). NIK-activated noncanonical NF-κB induced expression of IL-23 in DCs, contributing to the maintenance of T H 17 cells and type 3 ILCs. Consistent with the dual functions of IL-23 and IL-17 in mucosal immunity and inflammation, NIK deficiency also ameliorated colitis induction. Thus, our data suggest a pivotal role for the NIK signaling axis in regulating DC functions in intestinal immunity and homeostasis.

The transcription factor NF-κB regulates multiple aspects of innate and adaptive immune functions and serves as a pivotal mediator of inflammatory responses. NF-κB induces the expression of various pro-inflammatory genes, including those encoding cytokines and chemokines, and also participates in inflammasome regulation. In addition, NF-κB plays a critical role in regulating the survival, activation and differentiation of innate immune cells and inflammatory T cells. Consequently, deregulated NF-κB activation contributes to the pathogenic processes of various inflammatory diseases. In this review, we will discuss the activation and function of NF-κB in association with inflammatory diseases and highlight the development of therapeutic strategies based on NF-κB inhibition.

The mechanistic target of rapamycin (mTOR) has a key role in the integration of various physiological stimuli to regulate several cell growth and metabolic pathways. mTOR primarily functions as a catalytic subunit in two structurally related but functionally distinct multi-component kinase complexes, mTOR complex 1 (mTORC1) and mTORC2 (refs 1, 2). Dysregulation of mTOR signalling is associated with a variety of human diseases, including metabolic disorders and cancer. Thus, both mTORC1 and mTORC2 kinase activity is tightly controlled in cells. mTORC1 is activated by both nutrients and growth factors, whereas mTORC2 responds primarily to extracellular cues such as growth-factor-triggered activation of PI3K signalling. Although both mTOR and GβL (also known as MLST8) assemble into mTORC1 and mTORC2 (refs 11, 12, 13, 14, 15), it remains largely unclear what drives the dynamic assembly of these two functionally distinct complexes. Here we show, in humans and mice, that the K63-linked polyubiquitination status of GβL dictates the homeostasis of mTORC2 formation and activation. Mechanistically, the TRAF2 E3 ubiquitin ligase promotes K63-linked polyubiquitination of GβL, which disrupts its interaction with the unique mTORC2 component SIN1 (refs 12, 13, 14) to favour mTORC1 formation. By contrast, the OTUD7B deubiquitinase removes polyubiquitin chains from GβL to promote GβL interaction with SIN1, facilitating mTORC2 formation in response to various growth signals. Moreover, loss of critical ubiquitination residues in GβL, by either K305R/K313R mutations or a melanoma-associated GβL(ΔW297) truncation, leads to elevated mTORC2 formation, which facilitates tumorigenesis, in part by activating AKT oncogenic signalling. In support of a physiologically pivotal role for OTUD7B in the activation of mTORC2/AKT signalling, genetic deletion of Otud7b in mice suppresses Akt activation and Kras-driven lung tumorigenesis in vivo. Collectively, our study reveals a GβL-ubiquitination-dependent switch that fine-tunes the dynamic organization and activation of the mTORC2 kinase under both physiological and pathological conditions.

The transcription factor NF-kappa B regulates multiple aspects of innate and adaptive immune functions and serves as a pivotal mediator of inflammatory responses. NF-kappa B induces the expression of various pro-inflammatory genes, including those encoding cytokines and chemokines, and also participates in inflammasome regulation. In addition, NF-kappa B plays a critical role in regulating the survival, activation and differentiation of innate immune cells and inflammatory T cells. Consequently, deregulated NF-kappa B activation contributes to the pathogenic processes of various inflammatory diseases. In this review, we will discuss the activation and function of NF-kappa B in association with inflammatory diseases and highlight the development of therapeutic strategies based on NF-kappa B inhibition.

Cancer cells have different characteristics due to the genetic differences where these unique features may strongly influence the effectiveness of therapeutic interventions. Here, we show that the spontaneous reactivation of extracellular signalregulated kinase (ERK), distinct from conventional ERK activation, represents a potent mechanism for cancer cell survival. We studied ERK1/2 activation in vitro in SW480 colorectal cancer cells. Although ERK signaling tends to be transiently activated, we observed the delayed reactivation of ERK1/2 in epidermal growth factor (EGF)-stimulated SW480 cells. This effect was observed even after EGF withdrawal. While phosphorylated ERK1/2 translocated into the nucleus following its primary activation, it remained in the cytoplasm during late-phase activation. The inhibition of primary ERK1/2 activation or protein trafficking, blocked reactivation and concurrently increased caspase 3 activity. Our results suggest that the biphasic activation of ERK1/2 plays a role in cancer cell survival; thus, regulation of ERK1/2 activation may improve the efficacy of cancer therapies that target ERK signaling. [BMB Reports 2016; 49(4): 220-225]

Cell death and survival signaling pathways have opposed but fundamental functions for various cellular processes and maintain cell homeostasis through cross talk. Here we report a novel mechanism of interaction between these two pathways through the cleavage of RNF31 by caspases. RNF31, a component of the linear ubiquitin chain assembly complex (LUBAC), regulates cell survival by inducing linear ubiquitination of NF-κB signaling components. We found that RNF31 is cleaved under apoptosis conditions through various stimulations. The effector caspases caspase 3 and caspase 6 are responsible for this event, and aspartates 348, 387, and 390 were identified as target sites for this cleavage. Cleavage of RNF31 suppressed its ability to activate NF-κB signaling; thus, mutation of cleavage sites inhibited the induction of apoptosis by treatment with tumor necrosis factor alpha (TNF-α). Our findings elucidate a novel regulatory loop between cell death and the survival signal and may provide guidance for the development of therapeutic strategies for cancers through the sensitization of tumor cells to death-inducing drugs.

The proto-oncogene c-Maf is a transcription factor that plays a critical role in the differentiation of various T helper (T(H)) cell subsets. The amount of c-Maf increases after stimulation of the T cell receptor (TCR), which results in the production of multiple cytokines. We showed that two essential regulators of the transcription factor nuclear factor κB (NF-κB), the scaffold protein CARMA1 and the kinase IKKβ [inhibitor of NF-κB (IκB) kinase β], are also critical for the activation of c-Maf. Although CARMA1 deficiency did not affect the TCR-dependent increase in c-Maf abundance in T cells, CARMA1-dependent activation of the IKK complex was required for the nuclear translocation of c-Maf and its binding to the promoters of its target genes. Consistent with a role for c-Maf in the development of T follicular helper (T(FH)) cells, which provide help to B cells in the germinal centers of the spleen, CARMA1- or IKKβ-deficient mice immunized with peptide antigen had defects in the generation of T(FH) cells, formation of germinal centers, and production of antigen-specific antibodies. Together, these data suggest a mechanism by which c-Maf is regulated during T cell activation and differentiation.