IL-6 as a keystone cytokine in health and disease

Investigation into potential allergenicity of DBD plasma-treated casein digestion products based on immunoglobulin E linear epitopes and the sensitized-cell model

The study aimed to investigate the allergenicity change in casein treated with dielectric barrier discharge (DBD) plasma during in vitro simulated digestion, focusing on the immunoglobulin E (IgE) linear epitopes and utilizing a sensitized-cell model. Results indicated that prior treatment with DBD plasma treatment (4 min) before simulated digestion led to a 10.5% reduction in the IgE-binding capacity of casein digestion products. Moreover, the release of biologically active substances induced from KU812 cells, including β-HEX release rate, human histamine, IL-4, IL-6, and TNF-α, decreased by 2.1, 28.1, 20.6, 11.6, and 17.3%, respectively. Through a combined analysis of LC-MS/MS and immunoinformatics tools, it was revealed that DBD plasma treatment promoted the degradation of the IgE linear epitopes of casein during digestion, particularly those located in the α-helix region of αs1-CN and αs2-CN. These findings suggest that DBD plasma treatment prior to digestion may alleviate casein allergic reactions.

NF-κB p65 and TCF-4 interactions are associated with LPS-stimulated IL-6 secretion of macrophages

Proinflammatory cytokine plays a central role in host defense and acute inflammatory responses. Both positive and negative correlations of NF-κB and Wnt/β-catenin pathways have been reported depending on cell types in response to inflammatory stimuli for IL-6 cytokine production. Macrophages are vital to the regulation of immune responses and the development of inflammation, but the crosstalk between two pathways has not been elucidated so far in macrophages. We observed a positive cross-regulation between the NF-κB and Wnt/β-catenin pathways for IL-6 production in human macrophages. To verify the functional validity of this interaction, LY294002 or PNU74654, representative blockers of each pathway, were treated. IL-6 secretion was reduced to the basal level by both inhibitor treatments, even when stimulated by LPS. We also found that NF-κB p65 migrated to the nucleus and interacted with the transcription factor TCF-4 in macrophages upon LPS stimulation.

Effects of andiroba oil (Carapa guianensis aublet) on the immune system in inflammation and wound healing: A scoping review

ETHNOPHARMACOLOGICAL RELEVANCE

Andiroba seed oil (Carapa guianensis Aubl.) is widely used by traditional populations in tropical countries, especially in the Brazilian Amazon, because of its anti-inflammatory, antirheumatic, antiseptic, healing and antipyretic properties, among others, which makes it useful for the treatment, mainly, of skin afflictions and wounds.

AIM OF THE STUDY

To describe the modulation of the immune system by andiroba oil (Carapa guianensis Aubl.) in inflammation and wound healing.

MATERIALS AND METHODS

A scoping review was performed, following the recommendations of the Joanna Briggs Institute (JBI) and PRISMA for Scoping Reviews (PRISMA-ScR). As inclusion criteria, in vitro, in vivo, ex vivo, and clinical studies were selected, in Portuguese, English, or Spanish, in thirteen databases of published studies, gray literature, and references of the included studies, which deal with immune modulation by andiroba oil in the context of the various therapeutic applications that make use of its anti-inflammatory and wound healing properties. The selection of information sources was carried out by two independent reviewers between November 2022 and January 2023. The process of data extraction and evidence analysis was conducted by four pairs of independent reviewers between January and February 2023.

RESULTS

22 sources of evidence were included in this scoping review, mostly scientific articles published between 2005 and 2021 with in vivo sampling. The evidence suggests that andiroba oil reduces inflammation and promotes the healing of wounds of multiple etiologies by reducing leukocyte infiltration, increasing phagocytic activity, enhancing interleukin and inflammatory cytokine activity, promoting fibroblast recovery, increasing growth factors, reducing apoptotic cells, promoting reepithelialization, as well as promoting angiogenesis, reducing edema, and stimulating the production of glucocorticoids that alleviate pain. Additionally, different formulations of the oil (such as nanoemulsions, films and gels) are more effective in modulating inflammation and wound healing compared to in natura oil.

CONCLUSIONS

Evidence in the literature suggests that andiroba oil (Carapa guianensis Aubl.) has positive effects on immune modulation in inflammation and wound healing, which makes it a biocompound with high therapeutic potential.

Immune analysis of urine and plasma samples from patients with clear cell renal cell carcinoma

Clear cell renal cell carcinoma (ccRCC) is the third most common type of urological malignancy worldwide, and it is associated with a silent progression and late manifestation. Patients with a metastatic form of ccRCC have a poor prognosis; however, when the disease is diagnosed early, it is largely curable. Currently, there are no biomarkers available in clinical practice for ccRCC. Thus, the aim of the present study was to measure 27 biologically relevant cytokines in preoperative and postoperative urine samples, and in preoperative plasma samples from 34 patients with ccRCC, and to evaluate their diagnostic significance. The concentrations of cytokines were assessed by multiplex immune assay. The results showed significantly higher levels of IL-1 receptor antagonist, IL-6, IL-15, chemokine (C-C motif) ligand (CCL)2, CCL3, CCL4, C-X-C motif ligand (CXCL)10, granulocyte-macrophage colony stimulating factor (GM-CSF) and platelet-derived growth factor-BB (PDGF-BB), and lower levels of granulocyte colony stimulating factor (G-CSF) in urine samples from patients prior to surgery compared with those in the controls. Notably, the urine levels of G-CSF, IL-5 and vascular endothelial growth factor differed following tumor removal compared with the preoperative urine levels. In addition, urinary G-CSF, GM-CSF, IL-6, CXCL10, CCL5 and PDGF-BB appeared to be potential markers of tumor grade. Plasma from patients with ccRCC contained significantly higher levels of IL-6 and lower levels of CCL2 than control plasma. In conclusion, the present findings indicated that urinary and circulating cytokines may represent a promising novel tool for the early diagnosis of ccRCC and/or prediction of tumor grade.

Potential biomarkers for immune monitoring after renal transplantation

Renal transplantation represents the foremost efficacious approach for ameliorating end-stage renal disease. Despite the current state of advanced renal transplantation techniques and the established postoperative immunosuppression strategy, a subset of patients continues to experience immune rejection during both the early and late postoperative phases, ultimately leading to graft loss. Consequently, the identification of immunobiomarkers capable of predicting the onset of immune rejection becomes imperative in order to facilitate early intervention strategies and enhance long-term prognoses. Upon reviewing the pertinent literature, we identified several indicators that could potentially serve as immune biomarkers to varying extents. These include the T1/T2 ratio, Treg/Th17 ratio, IL-10/TNF-α ratio, IL-33, IL-34, IL-6, IL-4, other cytokines, and NOX2/4.

IL-6/STAT3 axis is hijacked by GCRV to facilitate viral replication via suppressing type Ⅰ IFN signaling

Grass carp reovirus (GCRV) infections and hemorrhagic disease (GCHD) outbreaks are typically seasonally periodic and temperature-dependent, yet the molecular mechanism remains unclear. Herein, we depicted that temperature-dependent IL-6/STAT3 axis was exploited by GCRV to facilitate viral replication via suppressing type Ⅰ IFN signaling. Combined multi-omics analysis and qPCR identified IL-6, STAT3, and IRF3 as potential effector molecules mediating GCRV infection. Deploying GCRV challenge at 18 °C and 28 °C as models of resistant and permissive infections and switched to the corresponding temperatures as temperature stress models, we illustrated that IL-6 and STAT3 expression, genome level of GCRV, and phosphorylation of STAT3 were temperature dependent and regulated by temperature stress. Further research revealed that activating IL-6/STAT3 axis enhanced GCRV replication and suppressed the expression of IFNs, whereas blocking the axis impaired viral replication. Mechanistically, grass carp STAT3 inhibited IRF3 nuclear translocation via interacting with it, thus down-regulating IFNs expression, restraining transcriptional activation of the IFN promoter, and facilitating GCRV replication. Overall, our work sheds light on an immune evasion mechanism whereby GCRV facilitates viral replication by hijacking IL-6/STAT3 axis to down-regulate IFNs expression, thus providing a valuable reference for targeted prevention and therapy of GCRV.

PM2.5 exposure upregulates pro-inflammatory protein expression in human microglial cells via oxidant stress and TLR4/NF-κB pathway

Exposure to ambient PM2.5 is associated with neurodegenerative disorders, in which microglia activation plays a critical role. Thus far, the underlying mechanisms for PM2.5-induced microglia activation have not been well elucidated. In this study, a human microglial cell line (HMC3) was used as the in vitro model to examine the inflammatory effect (hall marker of microglia activation) of PM2.5 and regulatory pathways. The expression of inflammatory mediators including interleukin-6 (IL-6) and cyclooxygenase-2 (COX-2) as well as the brain derived neurotrophic factor (BDNF) were determined by ELISA and/or real-time PCR, respectively. Flow cytometry was used to measure the production of intracellular reactive oxygen species (ROS). Western blot was used to measure protein levels of Toll-like receptor 4 (TLR4), NF-κB inhibitor α (IκBα) and COX-2. It was shown that PM2.5 stimulation increased IL-6 and COX-2 expression but decreased BDNF expression in a dose-dependent manner. Further studies showed that PM2.5 triggered the formation of ROS and pre-treatment with the ROS scavenger acetylcysteine (NAC) significantly suppressed PM2.5-induced IL-6 and COX-2 expression. Moreover, the nuclear factor kappa B (NF-κB) inhibitor BAY11-7085 or the TLR4 neutralizing antibody markedly blocked PM2.5-induced IL-6 and COX-2 expression. However, NAC or BAY11-7085 exhibited minimal effect on PM2.5-induced BDNF down-regulation. In addition, pre-treatment with BAY11-7085 or TLR4 neutralizing antibody reduced ROS production induced by PM2.5, and NAC pre-treatment inhibited TLR4 expression and NF-κB activation induced by PM2.5. Collectively, PM2.5 treatment induced IL-6 and COX-2 but suppressed BDNF expression. PM2.5-induced IL-6 and COX-2 expression was mediated by interactive oxidative stress and TLR4/NF-κB pathway.

The currrent landscape of antifibrotic therapy across different organs: A systematic approach

Fibrosis is a common pathological process that can affect virtually all the organs, but there are hardly any effective therapeutic options. This has led to an intense search for antifibrotic therapies over the last decades, with a great number of clinical assays currently underway. We have systematically reviewed all current and recently finished clinical trials involved in the development of new antifibrotic drugs, and the preclinical studies analyzing the relevance of each of these pharmacological strategies in fibrotic processes affecting tissues beyond those being clinically studied. We analyze and discuss this information with the aim of determining the most promising options and the feasibility of extending their therapeutic value as antifibrotic agents to other fibrotic conditions.

Systemic immunological responses are dependent on sex and ovarian hormone presence following acute inhaled woodsmoke exposure

BACKGROUND

Rural regions of the western United States have experienced a noticeable surge in both the frequency and severity of acute wildfire events, which brings significant challenges to both public safety and environmental conservation efforts, with impacts felt globally. Identifying factors contributing to immune dysfunction, including endocrinological phenotypes, is essential to understanding how hormones may influence toxicological susceptibility.

METHODS

This exploratory study utilized male and female C57BL/6 mice as in vivo models to investigate distinct responses to acute woodsmoke (WS) exposure with a focus on sex-based differences. In a second set of investigations, two groups were established within the female mouse cohort. In one group, mice experienced ovariectomy (OVX) to simulate an ovarian hormone-deficient state similar to surgical menopause, while the other group received Sham surgery as controls, to investigate the mechanistic role of ovarian hormone presence in driving immune dysregulation following acute WS exposure. Each experimental cohort followed a consecutive 2-day protocol with daily 4-h exposure intervals under two conditions: control HEPA-filtered air (FA) and acute WS to simulate an acute wildfire episode.

RESULTS

Metals analysis of WS particulate matter (PM) revealed significantly increased levels of 63Cu, 182W, 208Pb, and 238U, compared to filtered air (FA) controls, providing insights into the specific metal components most impacted by the changing dynamics of wildfire occurrences in the region. Male and female mice exhibited diverse patterns in lung mRNA cytokine expression following WS exposure, with males showing downregulation and females displaying upregulation, notably for IL-1β, TNF-α, CXCL-1, CCL-5, TGF-β, and IL-6. After acute WS exposure, there were notable differences in the responses of macrophages, neutrophils, and bronchoalveolar lavage (BAL) cytokines IL-10, IL-6, IL-1β, and TNF-α. Significant diverse alterations were observed in BAL cytokines, specifically IL-1β, IL-10, IL-6, and TNF-α, as well as in the populations of immune cells, such as macrophages and polymorphonuclear leukocytes, in both Sham and OVX mice, following acute WS exposure. These findings elucidated the profound influence of hormonal changes on inflammatory outcomes, delineating substantial sex-related differences in immune activation and revealing altered immune responses in OVX mice due to ovarian hormone deficiency. In addition, the flow cytometry analysis highlighted the complex interaction between OVX surgery, acute WS exposure, and their collective impact on immune cell populations within the hematopoietic bone marrow niche.

CONCLUSIONS

In summary, both male and female mice, alongside females subjected to OVX and those who had sham surgery, exhibit significant variations in the expression of proinflammatory cytokines, chemokines, lung mRNA gene expression, and related functional networks linked to signaling pathways. These differences potentially act as mediators of sex-specific and hormonal influences in the systemic inflammatory response to acute WS exposure during a wildfire event. Understanding the regulatory roles of genes expressed differentially under environmental stressors holds considerable implications, aiding in identifying sex-specific therapeutic targets for addressing acute lung inflammation and injury.

Genetic analyses unravel the causal association of cytokine levels on lichen simplex chronicus risk: insights from a mendelian randomization study

Lichen simplex chronicus (LSC) presents a challenge in dermatology due to its elusive pathogenic mechanisms. While associations between circulating inflammatory cytokines and LSC were observed, the definitive causal dynamics remain to be elucidated. Our study used a two-sample Mendelian randomization (MR) approach to investigate causal relationships. We applied a suite of MR methodologies, including IVW, Weighted Median, MR-Egger, Weighted Mode, Simple Mode, MR-PRESSO, and the Steiger test, to ensure robust causal inference. Our analysis confirmed the causal impact of genetically determined cytokine levels on LSC risk, particularly MMP-10 (OR = 0.493, P = 0.004) and DNER (OR = 0.651, P = 0.043) in risk attenuation. We also found a positive causal correlation between GDNF levels (OR = 1.871, P = 0.007) and LSC prevalence. Notably, bidirectional causality was observed between DNER and LSC. Consistency across various MR analyses and sensitivity analyses confirmed the absence of horizontal pleiotropy, validating the causal estimates. This pioneering MR investigation unveils a novel genetically anchored causal relationship between the circulating levels of MMP-10, DNER, and GDNF and LSC risk. Although further validation is requisite, our findings augment the understanding of cytokine mediation in LSC and underscore prospective avenues for research.

The "Heater" of "Cold" Tumors-Blocking IL-6

The resolution of inflammation is not simply the end of the inflammatory response but rather a complex process that involves various cells, inflammatory factors, and specialized proresolving mediators following the occurrence of inflammation. Once inflammation cannot be cleared by the body, malignant tumors may be induced. Among them, IL-6, as an immunosuppressive factor, activates a variety of signal transduction pathways and induces tumorigenesis. Monitoring IL-6 can be used for the diagnosis, efficacy evaluation and prognosis of tumor patients. In terms of treatment, improving the efficacy of targeted and immunotherapy remains a major challenge. Blocking IL-6 and its mediated signaling pathways can regulate the tumor immune microenvironment and enhance immunotherapy responses by activating immune cells. Even transform "cold" tumors that are difficult to respond to immunotherapy into immunogenic "hot" tumors, acting as a "heater" for "cold" tumors, restarting the tumor immune cycle, and reducing immunotherapy-related toxic reactions and drug resistance. In clinical practice, the combined application of IL-6 inhibition with targeted therapy and immunotherapy may produce synergistic results. Nevertheless, additional clinical trials are imperative to further validate the safety and efficacy of this therapeutic approach.

A transient brain endothelial translatome response to endotoxin is associated with mild cognitive changes post-shock in young mice

Sepsis-associated encephalopathy (SAE) is a common manifestation in septic patients that is associated with increased risk of long-term cognitive impairment. SAE is driven, at least in part, by brain endothelial dysfunction in response to systemic cytokine signaling. However, the mechanisms driving SAE and its consequences remain largely unknown. Here, we performed translating ribosome affinity purification and RNA-sequencing (TRAP-seq) from the brain endothelium to determine the transcriptional changes after an acute endotoxemic (LPS) challenge. LPS induced a strong acute transcriptional response in the brain endothelium that partially correlates with the whole brain transcriptional response and suggested an endothelial-specific hypoxia response. Consistent with a crucial role for IL-6, loss of the main regulator of this pathway, SOCS3, leads to a broadening of the population of genes responsive to LPS, suggesting that an overactivation of the IL-6/JAK/STAT3 pathway leads to an increased transcriptional response that could explain our prior findings of severe brain injury in these mice. To identify any potential sequelae of this acute response, we performed brain TRAP-seq following a battery of behavioral tests in mice after apparent recovery. We found that the transcriptional response returns to baseline within days post-challenge. Despite the transient nature of the response, we observed that mice that recovered from the endotoxemic shock showed mild, sex-dependent cognitive impairment, suggesting that the acute brain injury led to sustained, non-transcriptional effects. A better understanding of the transcriptional and non-transcriptional changes in response to shock is needed in order to prevent and/or revert the devastating consequences of septic shock.

Abstract Figure

Dietary L-carnitine supplementation modifies blood parameters of mid-lactating dairy cows during standardized lipopolysaccharide-induced inflammation

L-carnitine, available as feed additive, is essential for the beta-oxidation of free fatty acids in the mitochondrial matrix. It provides energy to immune cells and may positively impact the functionality of leukocytes during the acute phase response, a situation of high energy demand. To test this hypothesis, German Holstein cows were assigned to a control group (CON, n = 26) and an L-carnitine supplemented group (CAR, n = 27, rumen-protected L-carnitine product: 125 g/cow/d, corresponded to total L-carnitine intake: 25 g/cow/d, supplied with concentrate) and received an intravenous bolus injection of lipopolysaccharides (LPS, 0.5 µg/kg body weight, E. coli) on day 111 postpartum as a model of standardized systemic inflammation. Blood samples were collected from day 1 ante injectionem until day 14 post injectionem (pi), with frequent sampling through an indwelling venous catheter from 0.5 h pi to 12 h pi. All parameters of the white blood cell count responded significantly to LPS, while only a few parameters were affected by L-carnitine supplementation. The mean eosinophil count, as well as the percentage of basophils were significantly higher in CAR than in CON over time, which may be due to an increased membrane stability. However, phagocytosis and production of reactive oxygen species by leukocytes remained unchanged following L-carnitine supplementation. In conclusion, although supplementation with 25 g L-carnitine per cow and day resulted in increased proportions of specific leukocyte populations, it had only minor effects on the functional parameters studied in mid-lactating dairy cows during LPS-induced inflammation, and there was no evidence of direct improvement of immune functionality.

Interleukin-6 promotes visceral adipose tissue accumulation during aging via inhibiting fat lipolysis

BACKGROUND

Age-related visceral obesity could contribute to the development of cardiometabolic complications. The pathogenesis of visceral fat mass accumulation during the aging process remains complex and largely unknown. Interleukin-6 (IL-6) has emerged as one of the prominent inflammaging markers which are elevated in circulation during aging. However, the precise role of IL-6 in regulating age-related visceral adipose tissue accumulation remains uncertain.

RESULTS

A cross-sectional study including 77 older adults (≥65 years of age) was initially conducted. There was a significant positive association between serum IL-6 levels and visceral fat mass. We subsequently validated a modest but significant elevation in serum IL-6 levels in aged mice. Furthermore, we demonstrated that compared to wildtype control, IL-6 deficiency (IL-6 KO) significantly attenuated the accumulation of visceral adipose tissue during aging. Further metabolic characterization suggested that IL-6 deficiency resulted in improved lipid metabolism parameters and energy expenditure in aged mice. Moreover, histological examinations of adipose depots revealed that the absence of IL-6 ameliorated adipocyte hypertrophy in visceral adipose tissue of aged mice. Mechanically, the ablation of IL-6 could promote the PKA-mediated lipolysis and consequently mitigate lipid accumulation in adipose tissue in aged mice.

CONCLUSION

Our findings identify a detrimental role of IL-6 during the aging process by promoting visceral adipose tissue accumulation through inhibition of lipolysis. Therefore, strategies aimed at preventing or reducing IL-6 levels may potentially ameliorate age-related obesity and improve metabolism during aging.

Design and synthesis of new dihydropyrimidine/sulphonamide hybrids as promising anti-inflammatory agents via dual mPGES-1/5-LOX inhibition

A novel series of dihydropyrimidine/sulphonamide hybrids 3a-j with anti-inflammatory properties have been developed and tested as dual mPGES-1/5-LOX inhibitors. In vitro assay, results showed that compounds 3c, 3e, 3h, and 3j were the most effective dual inhibitors of mPGES-1 and 5-LOX activities. Compound 3j was the most potent dual inhibitor with IC50 values of 0.92 µM and 1.98 µM, respectively. In vivo, anti-inflammatory studies demonstrated that compounds 3c, 3e, 3h, and 3e had considerable anti-inflammatory activity, with EI% ranging from 29% to 71%. Compounds 3e and 3j were equivalent to celecoxib after the first hour but exhibited stronger anti-inflammatory effects than celecoxib after the third and fifth hours. Moreover, compounds 3e and 3j significantly reduced the levels of pro-inflammatory cytokines (PGE2, TNF-α, and IL-6) with gastrointestinal safety profiles. Molecular docking simulations explored the most potent derivatives' binding affinities and interaction patterns within mPGES-1 and 5-LOX active sites. This study disclosed that compound 3j is a promising anti-inflammatory lead with dual mPGES-1/5-LOX inhibition that deserves further preclinical investigation.

Serum Levels of Zinc, Albumin, Interleukin-6 and CRP in Patients with Unipolar and Bipolar Depression: Cross Sectional Study

Unipolar (UD) and bipolar depression (BDD) show a high degree of similarity in clinical presentations, which complicates the differential diagnosis of these disorders. The aim of this study was to investigate the serum levels of interleukin 6 (IL-6), C-reactive protein (CRP), albumin (Alb), and zinc (Zn) in patients with UD, BDD, and healthy controls (HC). A total of 211 samples were collected: 131 patient samples (65 UD and 68 BDD) and 80 HC. The Montgomery-Asberg Depression Rating Scale (MADRS), along with the Hamilton Depression Rating Scale (HAMD-17), were administered to patient groups to evaluate symptoms. A cross-sectional study was performed to analyse the serum levels of IL-6, CRP, albumin, and zinc. The concentration of CRP was determined using the immunoturbidimetry method, zinc using the colorimetric method, and albumin using the colorimetric method with bromocresol green on the Alinity c device. IL-6 cytokine concentration in serum samples was ascertained using a commercial enzyme immunoassay, ELISA. We found no significant differences in serum concentrations of zinc, albumin, CRP, and IL-6 between the groups of patients with unipolar and bipolar depression. There was a significant statistical difference (p < 0.001) between serum levels of all investigated parameters in both groups of depressed patients in comparison with HC. Furthermore, correlations with specific items on HAMD-17; (namely, hypochondrias, work and activities, somatic symptoms-general, and weight loss) and on MADRS (concentration difficulties, lassitude) were observed in both patient groups. These findings confirm the presence of low-grade inflammation in depression, thus adding better insight into the inflammation hypothesis directed to explain the aetiology of depressive disorders. Our results do not indicate potential biomarkers for distinguishing between unipolar and bipolar depression.

Interleukin 6 at menstruation promotes the proliferation and self-renewal of endometrial mesenchymal stromal/stem cells through the WNT/β-catenin signaling pathway

Background

At menstruation, the functional layer of the human endometrium sheds off due to the trigger of the release of inflammatory factors, including interleukin 6 (IL-6), as a result of a sharp decline in progesterone levels, leading to tissue breakdown and bleeding. The endometrial mesenchymal stem-like cells (CD140b+CD146+ eMSC) located in the basalis are responsible for the cyclical regeneration of the endometrium after menstruation. Endometrial cells from the menstruation phase have been proven to secrete a higher amount of IL-6 and further enhance the self-renewal and clonogenic activity of eMSC. However, the IL-6-responsive mechanism remains unknown. Thus, we hypothesized that IL-6 secreted from niche cells during menstruation regulates the proliferation and self-renewal of eMSC through the WNT/β-catenin signaling pathway.

Methods

In this study, the content of IL-6 across the menstrual phases was first evaluated. Coexpression of stem cell markers (CD140b and CD146) with interleukin 6 receptor (IL-6R) was confirmed by immunofluorescent staining. In vitro functional assays were conducted to investigate the effect of IL-6 on the cell activities of eMSC, and the therapeutic role of these IL-6- and WNT5A-pretreated eMSC on the repair of injured endometrium was observed using an established mouse model.

Results

The endometrial cells secrete a high amount of IL-6 under hypoxic conditions, which mimic the physiological microenvironment in the menstruation phase. Also, the expression of IL-6 receptors was confirmed in our eMSC, indicating their capacity to respond to IL-6 in the microenvironment. Exogenous IL-6 can significantly enhance the self-renewal, proliferation, and migrating capacity of eMSC. Activation of the WNT/β-catenin signaling pathway was observed upon IL-6 treatment, while suppression of the WNT/β-catenin signaling impaired the stimulatory role of IL-6 on eMSC activities. IL-6- and WNT5A-pretreated eMSC showed better performance during the regeneration of the injured mouse endometrium.

Conclusion

We demonstrate that the high level of IL-6 produced by endometrial cells at menstruation can induce the stem cells in the human endometrium to proliferate and migrate through the activation of the WNT/β-catenin pathway. Treatment of eMSC with IL-6 and WNT5A might enhance their therapeutic potential in the regeneration of injured endometrium.

A double-blind, placebo-controlled, randomized withdrawal trial of sarilumab for the treatment of glucocorticoid-dependent sarcoidosis

OBJECTIVES

Effective steroid-sparing therapies for the treatment of sarcoidosis are lacking; IL-6 antagonists may reduce sarcoidosis disease activity. This study assessed the safety and efficacy of the IL-6 receptor antagonist, sarilumab, in subjects with glucocorticoid-dependent sarcoidosis.

METHODS

This phase II, double-blind, placebo-controlled, randomized withdrawal trial enrolled 15 subjects with biopsy-proven sarcoidosis at Stanford University from November 2019 to September 2022. In period 1, subjects were treated with open-label s.c. sarilumab 200 mg every 2 weeks for 16 weeks, with predefined tapering of prednisone. Subjects who completed period 1 without a sarcoidosis flare entered period 2 and were randomized to continue sarilumab or to receive matching placebo for 12 weeks. The end points included flare-free survival, as well as changes in pulmonary function tests, chest imaging, patient-reported outcomes, and laboratory values.

RESULTS

Fifteen subjects were enrolled in the study (median age 57 years, 80% male, 73.3% White), and 10 subjects successfully completed period 1. During period 1, 4 of the 15 subjects (26.7%) discontinued due to worsening of their sarcoidosis, and CT chest imaging worsened in 5 of the 15 subjects (35.7%). During period 2, 0 of 2 subjects in the sarilumab group and 1 of 8 subjects (12.5%) in the placebo group had a flare. Treatment with sarilumab 200 mg was generally well tolerated in subjects with sarcoidosis.

CONCLUSION

In this double-blind, placebo-controlled, randomized withdrawal trial, a meaningful signal of improvement in subjects with sarcoidosis treated with sarilumab was not observed. Given the small numbers in this study, no definitive conclusions can be drawn.

TRIAL REGISTRATION

ClinicalTrials.gov, http://clinicaltrials.gov, NCT04008069.

Nanoadjuvant-triggered STING activation evokes systemic immunotherapy for repetitive implant-related infections

Repetitive implant-related infections (IRIs) are devastating complications in orthopedic surgery, threatening implant survival and even the life of the host. Biofilms conceal bacterial-associated antigens (BAAs) and result in a "cold tumor"-like immune silent microenvironment, allowing the persistence of IRIs. To address this challenge, an iron-based covalent organic framed nanoadjuvant doped with curcumin and platinum (CFCP) was designed in the present study to achieve efficient treatment of IRIs by inducing a systemic immune response. Specifically, enhanced sonodynamic therapy (SDT) from CFCP combined with iron ion metabolic interference increased the release of bacterial-associated double-stranded DNA (dsDNA). Immunogenic dsDNA promoted dendritic cell (DC) maturation through activation of the stimulator of interferon gene (STING) and amplified the immune stimulation of neutrophils via interferon-β (IFN-β). At the same time, enhanced BAA presentation aroused humoral immunity in B and T cells, creating long-term resistance to repetitive infections. Encouragingly, CFCP served as neoadjuvant immunotherapy for sustained antibacterial protection on implants and was expected to guide clinical IRI treatment and relapse prevention.

IL-6 Up-Regulates Expression of LIM-Domain Only Protein 4 in Psoriatic Keratinocytes through Activation of the MEK/ERK/NF-κB Pathway

Psoriasis is a chronic inflammatory skin disease characterized by the activation of keratinocytes and the infiltration of immune cells. Overexpression of the transcription factor LIM-domain only protein 4 (LMO4) promoted by IL-23 has critical roles in regulating the proliferation and differentiation of psoriatic keratinocytes. IL-6, an autocrine cytokine in psoriatic epidermis, is a key mediator of IL-23/T helper 17-driven cutaneous inflammation. However, little is known about how IL-6 regulates the up-regulation of LMO4 expression in psoriatic lesions. In this study, human immortalized keratinocyte cells, clinical biopsy specimens, and an animal model of psoriasis induced by imiquimod cream were used to investigate the role of IL-6 in the regulation of keratinocyte proliferation and differentiation. Psoriatic epidermis showed abnormal expression of IL-6 and LMO4. IL-6 up-regulated the expression of LMO4 and promoted keratinocyte proliferation and differentiation. Furthermore, in vitro and in vivo studies showed that IL-6 up-regulates LMO4 expression by activating the mitogen-activated extracellular signal-regulated kinase (MEK)/extracellular signal-regulated kinase (ERK)/NF-κB signaling pathway. These results suggest that IL-6 can activate the NF-κB signaling pathway, up-regulate the expression of LMO4, lead to abnormal proliferation and differentiation of keratinocytes, and promote the occurrence and development of psoriasis.

Targeting interleukin-6 as a treatment approach for peritoneal carcinomatosis

Peritoneal carcinomatosis (PC) is a complex manifestation of abdominal cancers, with a poor prognosis and limited treatment options. Recent work identifying high concentrations of the cytokine interleukin-6 (IL-6) and its soluble receptor (sIL-6-Rα) in the peritoneal cavity of patients with PC has highlighted this pathway as an emerging potential therapeutic target. This review article provides a comprehensive overview of the current understanding of the potential role of IL-6 in the development and progression of PC. We discuss mechansims by which the IL-6 pathway may contribute to peritoneal tumor dissemination, mesothelial adhesion and invasion, stromal invasion and proliferation, and immune response modulation. Finally, we review the prospects for targeting the IL-6 pathway in the treatment of PC, focusing on common sites of origin, including ovarian, gastric, pancreatic, colorectal and appendiceal cancer, and mesothelioma.

Sea Buckthorn Polysaccharide Ameliorates Colitis

Ulcerative colitis (UC) is characterized by chronic inflammation and ulceration of the intestinal inner lining, resulting in various symptoms. Sea buckthorn berries contain a bioactive compound known as sea buckthorn polysaccharide (SBP). However, the precise mechanisms underlying the impact of SBP on UC remain unclear. In this study, we investigated the effects of pretreatment with SBP on colitis induced by DSS. Our findings demonstrate that SBP pretreatment effectively reduces inflammation, oxidative stress, and intestinal barrier damage associated with colitis. To further elucidate the role of SBP-modulated gut microbiota in UC, we performed fecal microbiota transplantation (FMT) on DSS-treated mice. The microbiota from SBP-treated mice exhibits notable anti-inflammatory and antioxidant effects, improves colonic barrier integrity, and increases the abundance of beneficial bacteria, as well as enhancing SCFA production. Collectively, these results strongly indicate that SBP-mediated amelioration of colitis is attributed to its impact on the gut microbiota, particularly through the promotion of SCFA-producing bacteria and subsequent elevation of SCFA levels. This study provides compelling evidence supporting the efficacy of pre-emptive SBP supplementation in alleviating colitis symptoms by modulating the gut microbiota, thereby offering novel insights into the potential of SBP as a regulator of the gut microbiota for colitis relief.

Role of Inflammation in Depressive and Anxiety Disorders, Affect, and Cognition: Genetic and Non-Genetic Findings in the Lifelines Cohort Study

Background

Low-grade systemic inflammation is implicated in the pathogenesis of various neuropsychiatric conditions affecting mood and cognition. While much of the evidence concerns depression, large-scale population studies of anxiety, affect, and cognitive function are scarce. Importantly, causality remains unclear. We used complementary non-genetic, genetic risk score (GRS), and Mendelian randomization (MR) analyses to examine whether inflammatory markers are associated with affect, depressive and anxiety disorders, and cognitive performance in the Lifelines Cohort; and whether associations are likely to be causal.

Methods

Using data from up to 55,098 (59% female) individuals from the Dutch Lifelines cohort, we tested the cross-sectional and longitudinal associations of C-reactive protein (CRP) with (i) depressive and anxiety disorders; (ii) positive and negative affect scores, and (iii) five cognitive measures assessing attention, psychomotor speed, episodic memory, and executive functioning (figural fluency and working memory). Additionally, we examined the association between inflammatory marker GRSs (CRP, interleukin-6 [IL-6], IL-6 receptor [IL-6R and soluble IL-6R (sIL-6R)], glycoprotein acetyls [GlycA]) on these same outcomes (Nmax=57,946), followed by MR analysis examining evidence of causality of CRP on outcomes (Nmax=23,268). In genetic analyses, all GRSs and outcomes were z-transformed.

Results

In non-genetic analyses, higher CRP was associated with diagnosis of any depressive disorder, lower positive and higher negative affect scores, and worse performance on tests of figural fluency, attention, and psychomotor speed after adjusting for potential confounders, although the magnitude of these associations was small. In genetic analyses, CRPGRS was associated with any anxiety disorder (β=0.002, p=0.037, N=57,047) whereas GlycAGRS was associated with major depressive disorder (β=0.001, p=0.036; N=57,047). Both CRPGRS (β=0.006, p=0.035, N=57,946) and GlycAGRS (β=0.006, p=0.049; N=57,946) were associated with higher negative affect score. Inflammatory marker GRSs were not associated with cognitive performance, except sIL-6RGRS which was associated with poorer memory performance (β=-0.009, p=0.018, N=36,783). Further examination of the CRP-anxiety association using MR provided some weak evidence of causality (β=0.12; p=0.054).

Conclusions

Genetic and non-genetic analyses provide consistent evidence for an association between CRP and negative affect. Genetic analyses suggest that IL-6 signaling could be relevant for memory, and that the association between CRP and anxiety disorders could be causal. These results suggest that dysregulated immune physiology may impact a broad range of trans-diagnostic affective symptoms. However, given the small effect sizes and multiple tests conducted, future studies are required to investigate whether effects are moderated by sub-groups and whether these findings replicate in other cohorts.

Interleukin-6 signaling pathway in Mendelian randomization: A 10-year bibliometric analysis

Interleukin 6 (IL-6), a pleiotropic cytokine, is crucial in a variety of inflammatory and immunological disorders. In recent years, mendelian randomization, which is a widely used and successful method of analyzing causality, has recently been investigated for the relationship between the IL-6 pathway and related diseases. However, no studies have been conducted to review the research hotspots and trends in the field of IL-6 signaling pathway in Mendelian randomization. In this study, the Web of Science Core Collection (WoSCC) served as our literature source database to gather articles about the IL-6 signaling pathway in Mendelian randomization from 2013 to 2023. VOSviewer (version 1.6.18), Microsoft Excel 2021, and Scimago Graphica were employed for bibliometric and visualization analysis. A total of 164 documents that were written by 981 authors coming from 407 institutions across 41 countries and published in 107 journals were located from January 2013 to August 2023. With 64 and 25, respectively, England and the University of Bristol had the highest number of publications. Frontiers in Immunology is the most prolific journal, and Golam M Khandaker has published the highest number of significant articles. The most co-cited article was an article entitled the interleukin-6 receptor as a target for prevention of coronary-heart-disease: a Mendelian randomization analysis, written by Daniel I Swerdlow. The most popular keywords were "mendelian randomization," "interleukin-6," "il-6," "c-reactive protein," "association," "coronary-heart-disease," "inflammation," "instruments," "risk," "rheumatoid arthritis," "depression." The full extent of the existing literature over the last 10 years is systematically revealed in this study, which can provide readers with a valuable reference for fully comprehending the research hotspots and trends in the field of IL-6 signaling pathway in Mendelian randomization.

Alpha-1 adrenergic antagonists and the risk of hospitalization or death in non-hospitalized patients with COVID-19: A population-based study

BACKGROUND

Alpha-1 receptor antagonists may interfere with IL-6 signaling and could therefore be a potential treatment for COVID-19. However, the effectiveness of these drugs in mitigating the risk of clinical deterioration among non-hospitalized patients with COVID-19 is unknown.

OBJECTIVES

The aim of this study is to examine the association between alpha-1 antagonist exposure and the 30-day risk of a hospital encounter or death in nonhospitalized patients with COVID-19.

METHODS

We conducted a population-based cohort study of Ontario residents aged 35 years and older who were eligible for public drug coverage and who had a positive test for SARS-CoV-2 between January 1, 2020, and March 1, 2021. We matched each individual receiving an alpha-1 antagonist at the time of their positive test with two non-exposed individuals using propensity scores. Our outcome was a composite of a hospital admission, emergency department visit, or death, 1 to 30 days following the positive test.

RESULTS

We matched 3289 alpha-1 antagonist exposed patients to 6189 unexposed patients. Overall, there was no difference in the 30-day risk of the primary outcome among patients exposed to alpha-1 antagonists at the time of their diagnosis relative to unexposed individuals (28.8% vs. 28.0%; OR 1.00, 95% CI 0.91 to 1.11). In a secondary analysis, individuals exposed to alpha-1 antagonists had a lower risk of death in the 30 days following a COVID diagnosis (OR 0.79; 95% CI 0.66 to 0.93).

CONCLUSION

Alpha-1 antagonists did not mitigate the 30-day risk of clinical deterioration in non-hospitalized patients with COVID-19. Our findings do not support the general repurposing of alpha-1 antagonists as a treatment for such patients, although there may be subgroups of patients in whom further research is warranted.

Factors Associated with Mortality Among Severe Omicron Patients for COVID-19

Purpose

The purpose of the study was to explore the potential risk factors of mortality in patients with severe pneumonia during the omicron pandemic in South China in 2022.

Methods

Clinical data was collected from patients hospitalized with omicron COVID-19. Then, patients were categorized into the non-survival and survival groups. A comprehensive analysis was conducted to analyze the factors associated with negative outcome in individuals suffering from severe omicron COVID-19.

Results

In this study, 155 severe COVID-19 patients were included, comprising 55 non-survivors and 100 survivors. Non-survivors, in comparison to survivors, exhibited elevated levels of various biomarkers including neutrophil count, hypersensitive troponin T, urea, creatinine, C-reactive protein, procalcitonin, interleukin-6, plasma D-dimer, and derived neutrophil-to-lymphocyte ratio (dNLR) (P < 0.05). They also displayed reduced lymphocyte count, platelet count, and albumin levels (P < 0.05) and were more prone to developing comorbidities, including shock, acute cardiac and renal injury, acute respiratory distress syndrome, coagulation disorders, and secondary infections. Platelet count (PLT) <100 × 10^/L, interleukin-6 (IL-6) >100 pg/mL, and dNLR >5.0 independently contributed to the risk of death in patients suffering from severe COVID-19.

Conclusion

PLT, IL-6, and dNRL independently contributed to the risk of mortality in patients with severe pneumonia during the 2022 omicron pandemic in South China.

Navigating IL-6: From molecular mechanisms to therapeutic breakthroughs

This concise review navigates the intricate realm of Interleukin-6 (IL-6), an important member of the cytokine family. Beginning with an introduction to cytokines, this narrative review unfolds with the historical journey of IL-6, illuminating its evolving significance. A crucial section unravels the three distinct signaling modes employed by IL-6, providing a foundational understanding of its versatile interactions within cellular landscapes. Moving deeper, the review meticulously dissects IL-6's signaling mechanisms, unraveling the complexities of its pleiotropic effects in both physiological responses and pathological conditions. A significant focus is dedicated to the essential role IL-6 plays in inflammatory diseases, offering insights into its associations and implications for various health conditions. The review also takes a therapeutic turn by exploring the emergence of anti-IL-6 monoclonal inhibitors, marking a profound stride in treatment modalities. Diving into the molecular realm, the review explores small molecules as agents for IL-6 inhibition, providing a nuanced perspective on diverse intervention strategies. As the review embarks on the final chapters, it contemplates future aspects, offering glimpses into potential research trajectories and the evolving landscape of IL-6-related studies.

A comprehensive method for the phenotypical and functional characterization of recalled human memory B and T cells specific to vaccine antigens

Current methodologies for assessing vaccine effectiveness and longevity primarily center on measuring vaccine-induced neutralizing antibodies in serum or plasma. However, these methods overlook additional parameters such as the presence of memory B cells, even as antibody levels wane, and the pivotal role played by memory T cells in shaping antigen-specific memory B cell responses. Several studies have employed a combination of polyclonal activators, such as CpG and R848, along with various cytokines to provoke the recall of memory B cells from peripheral blood mononuclear cells (PBMCs) into antibody-secreting cells (ASCs). Other studies have examined the use of live attenuated viruses to stimulate antigen-specific memory T cells within PBMCs into effector T cells that produce Th1/Th2 cytokines. However, these studies have not fully elucidated the distinct effects of these polyclonal activators on individual subsets, nor have they evaluated whether the vaccine antigen alone is sufficient to trigger the recall of memory T cells. Thus, in this study, we directly compared the capacity of two B cell polyclonal activators to induce the transition of existing vaccine-specific memory cells present in peripheral blood samples into ASCs. Simultaneously, we also assessed the transition of existing memory T cells into effector subsets in response to vaccine antigens. Our findings demonstrate that both polyclonal activator combinations, CpG with IL-6 and IL-15, as well as R848 with IL-2, effectively induce the terminal differentiation of memory B cells into ASCs. Notably, CpG treatment preferentially expanded naïve and non-class-switched B cells, while R848 expanded class-switched memory cells, plasmablasts, and plasma cells. Consequently, R848 treatment led to a greater overall production of total and antigen-specific IgG immunoglobulins. Additionally, the exposure of isolated PBMCs to vaccine antigens alone proved sufficient for recalling the rare antigen-specific memory T cells into effector subsets, predominantly consisting of IFN-γ-producing CD4 T cells and TNF-β-producing CD8 T cells. This study not only establishes a rationale for the selection of methods to expand and detect antigen-specific lymphocyte subsets but also presents a means to quantify vaccine effectiveness by correlating serum antibody levels with preexisting memory cells within peripheral blood samples.

Salivary and Serum Interleukin-6: A Credible Marker for Predicting Oral Leukoplakia and Oral Squamous Cell Carcinoma by Enzyme-Linked Immunosorbent Assay (ELISA)

BACKGROUND

Oral squamous cell carcinoma (OSCC) is the most prevalent subtype of oral cancer. Detecting oral potentially malignant disorders (OPMDs) in their early stages is crucial to prevent their advancement into OSCC. One of the primary factors contributing to OSCC is tobacco use, which can lead to increased production of cytokines. Among these cytokines, interleukin-6 (IL-6), an immune molecule involved in inflammation, may serve as a valuable indicator for assessing the progression of OPMDs and OSCCs.

AIMS

The aim of this study is to assess the levels of IL6 in both serum and saliva using the enzyme-linked immunosorbent assay (ELISA) technique and to determine the prognostic value of these measurements in individuals with oral leukoplakia and OSCC.

MATERIALS AND METHODS

The research involved 45 participants, who were categorized into three groups: OSCC (15), leukoplakia (15), and a control group consisting of healthy individuals (15). Saliva and serum samples were collected from each individual within all three groups and analyzed using the ELISA method. Subsequently, the gathered data underwent statistical analysis for evaluation.

RESULTS

There were elevated levels of IL-6 in both saliva and serum among individuals with OSCC in comparison to those with leukoplakia and the healthy control group, and this difference was statistically significant. The analysis of ROC (Receiver Operating Characteristic) curves demonstrated that salivary IL-6 was a more effective indicator than serum IL-6 for detecting the advancement of OSCC. As the histological grade of differentiation increased in both OSCC and leukoplakia cases, there was a corresponding rise in salivary IL-6 levels.

CONCLUSION

Both salivary and serum IL-6 levels have the potential to serve as valuable prognostic biomarkers for oral leukoplakia and OSCC which shows possible involvement of IL-6 in the development and progression of these conditions. Salivary IL-6 is a superior prognostic marker compared to serum IL-6 due to its non-invasive nature which makes it a useful tool for mass screening.

IL-6 is a predictor and potential therapeutic target for coronavirus disease 2019-related heart failure: A single-center retrospective study

BACKGROUND

Inflammation is linked to coronavirus disease 2019 (COVID-19)-related heart failure (HF), but the specific mechanisms are unclear. This study aimed to assess the relationship between specific inflammatory factors, such as interleukin (IL)-1β, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12, IL-17, interferon (IFN)-α, and IFN-γ, and COVID-19-related HF.

METHODS

We retrospectively identified 212 adult patients with COVID-19 who were hospitalized at Shanghai Public Health Center from March 1 to May 30, 2022 (including 80 patients with HF and 132 without HF). High-sensitivity C-reactive protein (hs-CRP), procalcitonin (PCT), and inflammatory factors, including IL-1β, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12, IL-17, IFN-α, and IFN-γ, were compared between patients with COVID-19 with and without HF.

RESULTS

Patients with COVID-19 having and not having HF differed with regard to sex, age, hs-CRP, PCT, and IL-6 levels (p < 0.05). Logistic regression analysis indicated a significant positive association between IL and 6 and HF (odds ratio = 1.055; 95 % confidence interval: 1.019-1.093, p < 0.005). Sex, age, and hs-CRP were also associated with HF. Women had a greater risk of HF than men. Older age, higher levels of hs-CRP, and IL-6 were associated with a greater risk of HF.

CONCLUSIONS

In patients with COVID-19, increased IL-6 levels are significantly associated with COVID-19-related HF.

Translating B cell immunology to the treatment of antibody-mediated allograft rejection

Antibody-mediated rejection (AMR), including chronic AMR (cAMR), causes ~50% of kidney allograft losses each year. Despite attempts to develop well-tolerated and effective therapeutics for the management of AMR, to date, none has obtained FDA approval, thereby highlighting an urgent unmet medical need. Discoveries over the past decade from basic, translational and clinical studies of transplant recipients have provided a foundation for developing novel therapeutic approaches to preventing and treating AMR and cAMR. These interventions are aimed at reducing donor-specific antibody levels, decreasing graft injury and fibrosis, and preserving kidney function. Innovative approaches emerging from basic science findings include targeting interactions between alloreactive T cells and B cells, and depleting alloreactive memory B cells, as well as donor-specific antibody-producing plasmablasts and plasma cells. Therapies aimed at reducing the cytotoxic antibody effector functions mediated by natural killer cells and the complement system, and their associated pro-inflammatory cytokines, are also undergoing evaluation. The complexity of the pathogenesis of AMR and cAMR suggest that multiple approaches will probably be required to treat these disease processes effectively. Definitive answers await results from large, double-blind, multicentre, randomized controlled clinical trials.

Advances in desensitization for human leukocyte antigen incompatible kidney transplantation

PURPOSE OF REVIEW

Human leukocyte antigen (HLA) sensitization is a major barrier to kidney transplantation induced by exposure to alloantigens through pregnancy, blood product exposure and previous transplantations. Desensitization strategies are undertaken to improve the chances of finding compatible organ offers. Standard approaches to desensitization include the use of plasmapheresis/low dose intravenous immunoglobulin (IVIG) or high dose IVIG plus anti-CD20. However, current methods to reduce HLA antibodies are not always successful, especially in those with calculated panel reactive antibody 99-100%.

RECENT FINDINGS

Newer desensitization strategies such as imlifidase [immunoglobulin G (IgG) endopeptidase] rapidly inactivates IgG molecules and creates an "antibody-free zone", representing an important advancement in desensitization. However, pathogenic antibodies rebound, increasing allograft injury that is not addressed by imlifidase. Here, use of anti-IL-6R (tocilizumab) or anti-interleukin-6 (clazakizumab) could offer long-term control of B-memory and plasma cell DSA responses to limit graft injury. Agents aimed at long-lived plasma cells (anti-CD38 and anti-BCMAxCD3) could reduce or eliminate HLA-producing plasma cells from marrow niches. Other agents such as complement inhibitors and novel agents inhibiting the Fc neonatal receptor (FcRn) mediated IgG recycling will likely find important roles in desensitization.

SUMMARY

Use of these agents alone or in combination will likely improve the efficacy and durability of desensitization therapies, improving access to kidney transplantation for immunologically disadvantaged patients.

Study on the immunomodulatory mechanism of vitamin D in patients with unexplained recurrent spontaneous abortion

Background

To investigate the mechanism of vitamin D level on the regulation of peripheral blood lymphocyte subsets and serum Th1/Th2 cytokines in patients with unexplained recurrent spontaneous abortion (URSA).

Methods

Eighty female patients with URSA attending Sichuan Jinxin Xinan Women's and Children's Hospital from January 2020 to May 2021 were selected as the study group, and 30 age-matched women with a history of healthy deliveries were chosen as the control group, and peripheral blood lymphocyte subpopulations and serum Th1/Th2 cytokines of people with different levels of vitamin D were detected in the study group by flow cytometry, respectively. The results of immune factors before and after supplementation were analyzed in 40 of these patients with low vitamin D levels. The results of lymphoid subpopulations and Th1/Th2 cytokines in 19 patients with normal pregnancy before and after vitamin D supplementation and after normal pregnancy were also analyzed comparatively.

Results

(1) Serum 25(OH)D in the study group was lower than in the control group; peripheral blood Th cells, B cells and NK cells in the study group were higher than in the control group; IL-2, TNF-α, IFN-γ and IL-6 in the study group were higher than in the control group, while IL-4 and IL-10 in the study group were lower than in the control group (P < 0.05). (2) Th cells, B cells and NK cells of URSA patients in the vitamin D low level group were higher than those in the vitamin D normal group; serum cytokines IL-2, TNF-α and IFN-γ of patients in the vitamin D low level group were higher than those in the vitamin D normal group (P < 0.05); (3) Th cells, B cells and NK cells in URSA patients after vitamin D supplementation were lower than before vitamin D supplementation; serum cytokines IL-2, TNF-α and IFN-γ after vitamin D supplementation were lower than before vitamin D supplementation, IL-4 and IL-10 after vitamin D supplementation were higher than before vitamin D supplementation (P < 0.05), and there was no significant difference in IL-6 before and after vitamin D supplementation. (4) Th cells, B cells and NK cells in patients with normal pregnancy after vitamin D supplementation and after pregnancy were lower than those before vitamin D supplementation; serum cytokines IL-2, TNF-α and IFN-γ after vitamin D supplementation and after pregnancy were lower than those before vitamin D supplementation, and serum cytokines IL-4 and IL-10 after vitamin D supplementation and after pregnancy were higher than those before vitamin D supplementation, TNF -α, IFN-γ after pregnancy were lower than after vitamin D supplementation (P < 0.05), IL-6 was not significantly different before and after vitamin D supplementation and after pregnancy.

Conclusion

Vitamin D deficiency rate was high in URSA patients. Th、B、NK cells and IL-2, TNF-α, IFN-γ, IL-6 cytokines were high, while IL-6 and IL-10 were low in URSA patients. IL-2, TNF-α, IFN-γ cytokines and Th, B, NK cells were increased in vitamin D deficient URSA patients, and Vitamin D deficiency may be an important cause or aggravating factor of immune dysfunction in URSA patients. Vitamin D has an immunomodulatory effect on URSA patients, promoting successful pregnancy by down-regulating peripheral blood Th, B, and NK cells and IL-2, TNF-α, and IFN-γ cytokines, while up-regulating IL-4 and IL-10.

Structural insights into IL-6 signaling inhibition by therapeutic antibodies

Antibody inhibitors of the interleukin-6 (IL-6) signaling pathway, such as tocilizumab and sarilumab, have been used to treat rheumatoid arthritis, chimeric antigen receptor T cell-induced cytokine storm, and severe COVID-19 pneumonia. Here, we solve the cryogenic electron microscopy structures of sarilumab and tocilizumab in complex with IL-6R to resolutions of 3.2 and 3.3 Å, respectively. These structures reveal that both tocilizumab and sarilumab bind to the D3 domain of IL-6R. The binding surfaces of the two antibodies largely overlap, but the detailed interactions are different. Functional studies of various mutants show results consistent with our structural analysis of the antibodies and IL-6R interactions. Structural comparisons with the IL-6/IL-6R/gp130 complex indicate that sarilumab and tocilizumab probably inhibit IL-6/IL-6R signaling by competing for the IL-6 binding site. In summary, this work reveals the antibody-blocking mechanism of the IL-6 signaling pathway and paves the way for future antibody discovery.

A review of long non-coding RNAs in ankylosing spondylitis: pathogenesis, clinical assessment, and therapeutic targets

Ankylosing spondylitis (AS) is a chronic immune-mediated type of inflammatory arthritis characterized by inflammation, bone erosion, and stiffness of the spine and sacroiliac joints. Despite great efforts put into the investigation of the disease, the pathogenesis of AS remains unclear, posing challenges in identifying ideal targets for diagnosis and treatment. To enhance our understanding of AS, an increasing number of studies have been conducted. Some of these studies reveal that long non-coding RNAs (lncRNAs) play crucial roles in the etiology of AS. Some certain lncRNAs influence the development of AS by regulating inflammatory responses, autophagy, apoptosis, and adipogenesis, as well as the proliferation and differentiation of cells. Additionally, some lncRNAs demonstrate potential as biomarkers, aiding in monitoring disease progression and predicting prognosis. In this review, we summarize recent studies concerning lncRNAs in AS to elucidate the underlying mechanisms in which lncRNAs are involved and their potential values as biomarkers for disease assessment and druggable targets for therapy.

Targeting inflammation as cancer therapy

Inflammation has accompanied human beings since the emergence of wounds and infections. In the past decades, numerous efforts have been undertaken to explore the potential role of inflammation in cancer, from tumor development, invasion, and metastasis to the resistance of tumors to treatment. Inflammation-targeted agents not only demonstrate the potential to suppress cancer development, but also to improve the efficacy of other therapeutic modalities. In this review, we describe the highly dynamic and complex inflammatory tumor microenvironment, with discussion on key inflammation mediators in cancer including inflammatory cells, inflammatory cytokines, and their downstream intracellular pathways. In addition, we especially address the role of inflammation in cancer development and highlight the action mechanisms of inflammation-targeted therapies in antitumor response. Finally, we summarize the results from both preclinical and clinical studies up to date to illustrate the translation potential of inflammation-targeted therapies.

IRF1 Mediates Growth Arrest and the Induction of a Secretory Phenotype in Alveolar Epithelial Cells in Response to Inflammatory Cytokines IFNγ/TNFα

In COVID-19, cytokine release syndrome can cause severe lung tissue damage leading to acute respiratory distress syndrome (ARDS). Here, we address the effects of IFNγ, TNFα, IL-1β and IL-6 on the growth arrest of alveolar A549 cells, focusing on the role of the IFN regulatory factor 1 (IRF1) transcription factor. The efficacy of JAK1/2 inhibitor baricitinib has also been tested. A549 WT and IRF1 KO cells were exposed to cytokines for up to 72 h. Cell proliferation and death were evaluated with the resazurin assay, analysis of cell cycle and cycle-regulator proteins, LDH release and Annexin-V positivity; the induction of senescence and senescence-associated secretory phenotype (SASP) was evaluated through β-galactosidase staining and the quantitation of secreted inflammatory mediators. While IL-1 and IL-6 proved ineffective, IFNγ plus TNFα caused a proliferative arrest in A549 WT cells with alterations in cell morphology, along with the acquisition of a secretory phenotype. These effects were STAT and IRF1-dependent since they were prevented by baricitinib and much less evident in IRF1 KO than in WT cells. In alveolar cells, STATs/IRF1 axis is required for cytokine-induced proliferative arrest and the induction of a secretory phenotype. Hence, baricitininb is a promising therapeutic strategy for the attenuation of senescence-associated inflammation.

Fitness age outperforms body mass index in differentiating aging patterns and health risk profiles of healthy adults aged 51-80 years

Physical fitness has been extensively shown to strongly associate with general health status and major health risks. Here we tested the ability of a novel estimate of fitness age (FitAge) to differentiate aging trajectories.This study aimed at (1) testing the ability of FitAge to differentiate aging patterns among decelerated, normal, and accelerated agers in selected health domains, (2) estimating the risk for developing major health issues depending on the aging trajectory, and (3) comparing FitAge to body mass index (BMI) categorization in differentiating healthy from unhealthy aging patterns.A total of 176 volunteers participated in this cross-sectional study. Participants underwent clinical screening and a comprehensive assessment of body composition, nutritional and health-related status, cognitive functioning, and haematochemical analyses with routine tests, oxidative stress, and inflammation markers. Scores for major health risks were also computed.FitAge outperformed BMI in estimating major health risk scores and was able to differentiate decelerated from normal and accelerated agers for health risk profile and several physiological domains. Body composition, immune system activation, and inflammation markers emerged as those variables flagging the largest differences between decelerated and accelerated aging patterns.The novel estimate of biological aging can accurately differentiate both in women and men decelerated from accelerated agers in almost all the domains scrutinized. Overall, decelerated aging is linked to positively oriented features which associate with reduced risk of developing major health issues.The present findings have potential relevance and practical implications to identify individuals at higher risk of accelerated aging according to their FitAge estimated via simple and cost-effective motor tests.

Immunosuppressive effects of the mycotoxin patulin in macrophages

Patulin (PAT) is a fungi-derived secondary metabolite produced by numerous fungal species, especially within Aspergillus, Byssochlamys, and Penicillium genera, amongst which P. expansum is the foremost producer. Similar to other fungi-derived metabolites, PAT has been shown to have diverse biological features. Initially, PAT was used as an effective antimicrobial agent against Gram-negative and Gram-positive bacteria. Then, PAT has been shown to possess immunosuppressive properties encompassing humoral and cellular immune response, immune cell function and activation, phagocytosis, nitric oxide and reactive oxygen species production, cytokine release, and nuclear factor-κB and mitogen-activated protein kinases activation. Macrophages are a heterogeneous population of immune cells widely distributed throughout organs and connective tissue. The chief function of macrophages is to engulf and destroy foreign bodies through phagocytosis; this ability was fundamental to his discovery. However, macrophages play other well-established roles in immunity. Thus, considering the central role of macrophages in the immune response, we review the immunosuppressive effects of PAT in macrophages and provide the possible mechanisms of action.

Structural insights into IL-11-mediated signalling and human IL6ST variant-associated immunodeficiency

IL-11 and IL-6 activate signalling via assembly of the cell surface receptor gp130; however, it is unclear how signals are transmitted across the membrane to instruct cellular responses. Here we solve the cryoEM structure of the IL-11 receptor recognition complex to discover how differences in gp130-binding interfaces may drive signalling outcomes. We explore how mutations in the IL6ST gene encoding for gp130, which cause severe immune deficiencies in humans, impair signalling without blocking cytokine binding. We use cryoEM to solve structures of both IL-11 and IL-6 complexes with a mutant form of gp130 associated with human disease. Together with molecular dynamics simulations, we show that the disease-associated variant led to an increase in flexibility including motion within the cytokine-binding core and increased distance between extracellular domains. However, these distances are minimized as the transmembrane helix exits the membrane, suggesting a stringency in geometry for signalling and dimmer switch mode of action.

IL-6-Driven Autocrine Lactate Promotes Immune Escape of Uveal Melanoma

Purpose

Early metastasis, in which immune escape plays a crucial role, is the leading cause of death in patients with uveal melanoma (UM); however, the molecular mechanism underlying UM immune escape remains unclear, which greatly limits the clinical application of immunotherapy for metastatic UM.

Methods

Transcriptome profiles were revealed by RNA-seq analysis. TALL-104 and NK-92MI-mediated cell killing assays were used to examine the immune resistance of UM cells. The glycolysis rate was measured by extracellular acidification analysis. Protein stability was evaluated by CHX-chase assay. Immunofluorescence histochemistry was performed to detect protein levels in clinical UM specimens.

Results

Continuous exposure to IL-6 induced the expression of both PD-L1 and HLA-E in UM cells, which promoted UM immune escape. Transcriptome analysis revealed that the expression of most metabolic enzymes in the glycolysis pathway, especially the rate-limiting enzymes, PFKP and PKM, was upregulated, whereas enzymes involved in the acetyl-CoA synthesis pathway were downregulated after exposure to IL-6. Blocking the glycolytic pathway and lactate production by knocking down PKM and LDHA decreased PD-L1 and HLA-E protein, but not mRNA, levels in UM cells treated with IL-6. Notably, lactate secreted by IL-6-treated UM cells was crucial in influencing PD-L1 and HLA-E stability via the GPR81-cAMP-PKA signaling pathway.

Conclusions

Our data reveal a novel mechanism by which UM cells acquire an immune-escape phenotype by metabolic reprogramming and reinforce the importance of the link between inflammation and immune escape.

Family Disadvantage, Education, and Health Outcomes Among Black Youths Over a 20-Year Period

Importance

Upward mobility (via educational attainment) is highly valued, but longitudinal associations with mental and physical health among Black youths are less understood.

Objective

To examine associations of childhood family disadvantage and college graduation with adult mental and physical health in Black youths followed up into adulthood.

Design, Setting, and Participants

This longitudinal, prospective cohort study of Black youths from the state of Georgia who were studied for 20 years (ages 11 to 31 years) was conducted between 2001 and 2022. Participants for this study were drawn from the Strong African American Healthy Adults Program. Data analysis was conducted from April 2023 to January 2024.

Exposures

Family economic disadvantage (measured during the adolescent years) and college graduation (indicating upward mobility).

Main Outcomes and Measures

Primary outcomes included mental health, substance use, and physical health. Mental health included a composite of internalizing and disruptive problems (anxiety, depression, anger, aggressive behaviors, and emotional reactivity). Substance use included a composite of smoking, drinking, and drug use. Physical health included metabolic syndrome (MetS) and proinflammatory phenotypes (immune cells mounting exaggerated cytokine responses to bacterial challenge and being insensitive to inhibitory signals from glucocorticoids). Mental and physical health measures were taken at age 31 and during the adolescent years. Linear and logistic regression analyses, as well as mediated moderation analyses, were conducted.

Results

The study population consisted of 329 Black youths (212 women [64%]; 117 men [36%]; mean [SD] age at follow-up, 31 [1] years). Compared with those who did not graduate college, those who graduated from college had 0.14 SD fewer mental health problems (b = -1.377; 95% CI, -2.529 to -0.226; β = -0.137; P = .02) and 0.13 SD lower levels of substance use (b = -0.114; 95% CI, -0.210 to -0.018; β = -0.131; P = .02). Residualized change scores revealed that college graduates showed greater decreases from age 16 to 31 years in mental health problems (b = -1.267; 95% CI, -2.360 to -0.174; β = -0.133; P = .02) and substance use problems (b = -0.116; 95% CI, -0.211 to -0.021; β = -0.136; P = .02). For physical health, significant interactions between childhood family disadvantage and college completion emerged in association with MetS (OR, 1.495; 95% CI, 1.111-2.012; P = .008) and proinflammatory phenotype (b = 0.051; 95% CI, 0.003 to 0.099; β = 0.131; P = .04). Among youths growing up in disadvantaged households, college completion was associated with a 32.6% greater likelihood of MetS (OR, 3.947; 95% CI, 1.003-15.502; P = .049) and 0.59 SD more proinflammatory phenotype (mean difference, 0.249, 95% CI, 0.001 to 0.497; P = .049). Conversely, among those from economically advantaged backgrounds, college completion was correlated with lower MetS and less proinflammatory phenotype. Findings held after controlling for body mass index at age 19 years.

Conclusions and Relevance

In this longitudinal cohort study of Black youths, graduating from college was associated with an adult profile of better mental health but poorer physical health among those from economic disadvantage. These findings suggest that developing interventions that foster healthy outcomes across multiple life domains may be important for ensuring that striving for upward mobility is not accompanied by unintended cardiometabolic risk.

COVID-19 cooling: Nanostrategies targeting cytokine storm for controlling severe and critical symptoms

As severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants continue to wreak havoc worldwide, the "Cytokine Storm" (CS, also known as the inflammatory storm) or Cytokine Release Syndrome has reemerged in the public consciousness. CS is a significant contributor to the deterioration of infected individuals. Therefore, CS control is of great significance for the treatment of critically ill patients and the reduction of mortality rates. With the occurrence of variants, concerns regarding the efficacy of vaccines and antiviral drugs with a broad spectrum have grown. We should make an effort to modernize treatment strategies to address the challenges posed by mutations. Thus, in addition to the requirement for additional clinical data to monitor the long-term effects of vaccines and broad-spectrum antiviral drugs, we can use CS as an entry point and therapeutic target to alleviate the severity of the disease in patients. To effectively combat the mutation, new technologies for neutralizing or controlling CS must be developed. In recent years, nanotechnology has been widely applied in the biomedical field, opening up a plethora of opportunities for CS. Here, we put forward the view of cytokine storm as a therapeutic target can be used to treat critically ill patients by expounding the relationship between coronavirus disease 2019 (COVID-19) and CS and the mechanisms associated with CS. We pay special attention to the representative strategies of nanomaterials in current neutral and CS research, as well as their potential chemical design and principles. We hope that the nanostrategies described in this review provide attractive treatment options for severe and critical COVID-19 caused by CS.

The anti-inflammatory effect of metformin: The molecular targets

Metformin is an anti-diabetic drug. Metformin mainly inhibits gluconeogenesis in the liver and reduces blood sugar. In addition to the anti-diabetic effects, many studies have revealed that metformin has anti-inflammatory effects. Various molecules were suggested to be the target of the metformin's anti-inflammatory effects. However, the conclusion is not clear. Metformin is related to a number of molecules and the identification of the main target in anti-inflammatory effects leads to the understanding of inflammation and metformin. In this article, I discuss each suggested molecule, involved mechanisms, and their relationship with various diseases.

Exposure to parental depression in adolescence and proinflammatory phenotypes 20 years later

Although the biological embedding model of adversity proposes that stressful experiences in childhood create a durable proinflammatory phenotype in immune cells, research to date has relied on study designs that limit our ability to make conclusions about whether the phenotype is long-lasting. The present study leverages an ongoing 20-year investigation of African American youth to test research questions about the extent to which stressors measured in childhood forecast a proinflammatory phenotype in adulthood, as indicated by exaggerated cytokine responses to bacterial stimuli, monocyte insensitivity to inhibitory signals from hydrocortisone, and low-grade inflammation. Parents reported on their depressive symptoms and unsupportive parenting tendencies across youths' adolescence. At age 31, youth participants (now adults) completed a fasting blood draw. Samples were incubated with lipopolysaccharide and doses of hydrocortisone to evaluate proinflammatory processes. Additionally, blood samples were tested for indicators of low-grade inflammation, including IL-6, IL-8, IL-10, and TNF-α, and soluble urokinase plasminogen activator receptor. Analyses revealed that parental depression across youths' adolescence prospectively predicted indicators of proinflammatory phenotypes at age 31. Follow-up analyses suggested that unsupportive parenting mediated these associations. These findings suggest that exposure to parental depression in adolescence leaves an imprint on inflammatory activity that can be observed 20 years later.

IFITM3 mediates inflammation induced myocardial injury through JAK2/STAT3 signaling pathway

Myocarditis is an inflammation of the heart muscle often associated with viral infections and can lead to dilated cardiomyopathy. Interferon-induced transmembrane protein 3 (IFITM3) is a small endosomal membrane protein with anti-viral activity against multiple viruses and is also implicated in non-infectious diseases such as cancer and Alzheimer's Disease. Since the IFITM3 proteins are expressed both in T cells and in cardiomyocytes, it is reasonable to hypothesize that these molecules could affect myocarditis either through their effect on the autoimmune response or through direct modulation of cardiomyocyte damage. The aim of this study was to investigate the role of IFITM3 in experimental autoimmune myocarditis (EAM)-mediated myocardial injury. Immunization of rats with cardiac myosin results in substantial cardiac inflammation and is associated with increased expression of IFITM3 after 21 days. In vivo IFITM3 shRNA knockdown using the lentivirus transfection method reduced cardiac injury while restoring IFITM3 expression reversed the protective effect of IFITM3 RNA interference. To determine the direct impact of IFITM3, the rat ventricular cell line, H9c2, was treated with palmitic acid which causes apoptosis in these cells. Suppressing IFITM3 expression protects H9c2 cells while overexpressing IFITM3 enhances cell injury. JAK inhibitors reduced IFITM3-mediated myocardial cell injury. In conclusion, IFITM3 may mediate myocardial injury in EAM rats and palmitic acid-induced damage to H9c2 cells through the JAK2/STAT3 pathway.

Management of the sensitized pediatric renal transplant candidate

Kidney transplantation is the treatment of choice for patients with ESRD as it is associated with improved patient survival and better quality of life, especially in children. There are several barriers to a successful transplant including organ shortage, anatomic barriers, and immunologic barriers. One of the biggest immunologic barriers that precludes transplantation is sensitization, when patients have antibodies prior to transplantation, resulting in positive crossmatches with donor. 30%-40% of adult patients on the wait list are sensitized. There is a growing number of pediatric patients on the wait list who are sensitized. This poses a unique challenge to the pediatric transplant community. Therefore, attempts to perform desensitization to remove or suppress pathogenic HLA antibodies resulting in acceptable crossmatches, and ultimately a successful transplant, while reducing the risk of acute rejection, are much needed in these children. This review article aims to address the management of such patients both prior to transplantation, with strategies to overcome sensitization, and after transplantation with monitoring for allograft rejection and other complications.

Thymic Atrophy and Immune Dysregulation in Infants with Complex Congenital Heart Disease

Congenital heart disease (CHD) is the most common birth defect, and up to 50% of infants with CHD require cardiovascular surgery early in life. Current clinical practice often involves thymus resection during cardiac surgery, detrimentally affecting T-cell immunity. However, epidemiological data indicate that CHD patients face an elevated risk for infections and immune-mediated diseases, independent of thymectomy. Hence, we examined whether the cardiac defect impacts thymus function in individuals with CHD. We investigated thymocyte development in 58 infants categorized by CHD complexity. To assess the relationship between CHD complexity and thymic function, we analyzed T-cell development, thymic output, and biomarkers linked to cardiac defects, stress, or inflammation. Patients with highly complex CHD exhibit thymic atrophy, resulting in low frequencies of recent thymic emigrants in peripheral blood, even prior to thymectomy. Elevated plasma cortisol levels were detected in all CHD patients, while high NT-proBNP and IL-6 levels were associated with thymic atrophy. Our findings reveal an association between complex CHD and thymic atrophy, resulting in reduced thymic output. Consequently, thymus preservation during cardiovascular surgery could significantly enhance immune function and the long-term health of CHD patients.

Taming the cytokine storm: small molecule inhibitors targeting IL-6/IL-6α receptor

Given the increasing effectiveness of immune-based therapies, management of their associated toxicities is of utmost importance. Cytokine release syndrome (CRS), characterized by elevated levels of cytokine, poses a significant challenge following the administration of antibodies and CAR-T cell therapies. CRS also contributes to multiple organ dysfunction in severe viral infections, notably in COVID-19. Given the pivotal role of IL-6 cytokine in initiating CRS, it has been considered a most potential therapeutic target to mitigate hyperactivated immune responses. While monoclonal antibodies of IL-6 show promise in mitigating cytokine storm, concerns about immunotoxicity persist, and small molecule IL-6 antagonists remain unavailable. The present study employed sophisticated computational techniques to identify potential hit compounds as IL-6 inhibitors, with the aim of inhibiting IL-6/IL-6R protein-protein interactions. Through ligand-based pharmacophore mapping and shape similarity in combination with docking-based screening, we identified nine hit compounds with diverse chemical scaffolds as potential binders of IL-6. Further, the MD simulation of 300 ns of five virtual hits in a complex with IL-6 was employed to study the dynamic behavior. To provide a more precise prediction, binding free energy was also estimated. The identified compounds persistently interacted with the residues lining the binding site of the IL-6 protein. These compounds displayed low binding energy during MMPBSA calculations, substantiating their strong association with IL-6. This study suggests promising scaffolds as potential inhibitors of IL-6/IL-6R protein-protein interactions and provides direction for lead optimization.

Farnesoid X receptor promotes non-small cell lung cancer metastasis by activating Jak2/STAT3 signaling via transactivation of IL-6ST and IL-6 genes

Metastasis accounts for the majority of cases of cancer recurrence and death in patients with advanced non-small cell lung cancer (NSCLC). Farnesoid X Receptor (FXR) is a bile acid nuclear receptor that was recently found to be upregulated in NSCLC tissues. However, whether and how FXR regulates NSCLC metastasis remains unclear. In the present study, it was found that FXR promoted the migration, invasion, and angiogenic ability of NSCLC cells in vitro, and increased NSCLC metastasis in a mouse model in vivo. Mechanistic investigation demonstrated that FXR specifically bound to the promoters of IL-6ST and IL-6 genes to upregulate their transcription, thereby leading to activation of the Jak2/STAT3 signaling pathway, which facilitated tumor migration, invasion, and angiogenesis in NSCLC. Notably, Z-guggulsterone, a natural FXR inhibitor, significantly reduced FXRhigh NSCLC metastasis, and decreased the expression of FXR, IL-6, IL-6ST, and p-STAT3 in the mouse model. Clinical analysis verified that FXR was positively correlated with IL-6, IL-6ST and p-STAT3 expression in NSCLC patients, and was indicative of a poor prognosis. Collectively, these results highlight a novel FXR-induced IL-6/IL-6ST/Jak2/STAT3 axis in NSCLC metastasis, and a promising therapeutic means for treating FXRhigh metastatic NSCLC.