Search Results (14,213)

Mycobacterium bovis, the causative agent of bovine tuberculosis, infects and persists within macrophages, triggering pro-inflammatory responses. While these mechanisms are well characterized for Mycobacterium tuberculosis, less is known about host responses to M. bovis. Inflammasome activation and IL-1β production have been linked to ESAT-6, a substrate of the ESX-1 secretion system present in both species. Here, we examined inflammasome activation in bovine macrophages infected with the virulent M. bovis strain Mb04-303. M. bovis AF2122/97 and NCTC10772 upregulated IL-1β transcription, whereas Mb04-303 and BCG did not. Unexpectedly, deletion of the genes encoding ESAT-6 and CFP-10 from Mb04-303 enhanced inflammasome activation, as evidenced by increased NLRP3 and IL-1β transcription. Complementation with either wild-type ESAT-6/CFP-10 or the T63A ESAT-6 variant restored downregulation of the response, indicating that this substitution does not alter inflammasome modulation. In contrast, deletion of ESAT-6/CFP-10 from an attenuated M. bovis vaccine candidate reduced IL-1β transcription. No differences were observed between M. tuberculosis H37Rv and its ESAT-6-deficient mutant in bovine macrophages. Together, these findings demonstrate that ESAT-6/CFP-10-mediated modulation of inflammasome activation in bovine macrophages is highly dependent on the mycobacterial genetic background. Full article

Owing to the multifactorial nature of inflammatory bowel disease (IBD) pathogenesis, conventional two-dimensional (2D) models inadequately recapitulate the complex in vivo microenvironment. This study sought to develop an immune-microenvironment-integrated intestinal-on-a-chip model to overcome these limitations. A microfluidic chip was engineered to co-culture intestinal epithelial (Caco-2) cells and macrophages, facilitating the simulation of IBD pathological conditions for mechanistic investigations. Following inflammatory stimulation, M0 macrophages polarized into the M1 phenotype, concomitant with the upregulation of pro-inflammatory cytokines, including tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and interleukin-1 beta (IL-1β). This induction disrupted the expression of tight junction proteins (e.g., zonula occludens-1 [ZO-1]) in Caco-2 cells, thereby compromising epithelial barrier integrity. Infliximab was used as a model drug to inhibit TNF-α and modulate macrophage polarization within the chip, effectively rescuing impaired epithelial barrier integrity. This study establishes a reliable intestinal-on-a-chip model that recapitulates macrophage–epithelial interactions in IBD, providing a robust platform for elucidating the mechanisms underlying intestinal barrier dysfunction and developing targeted therapeutic strategies. Full article

Melanoma is an aggressive skin cancer with rapid progression and high metastatic potential, and resistance to current therapies remains a major clinical challenge. In this study, Listeria monocytogenes-derived membrane vesicles (LM MVs) were isolated, characterized, and evaluated for their immunomodulatory and antitumor activities. LM MVs showed an average diameter of approximately 160 nm and contained multiple bacterial proteins, including listeriolysin O. In vitro, LM MVs promoted pro-inflammatory activation of RAW264.7 macrophages, as indicated by increased CD80/CD86 expression and enhanced transcription of inflammatory mediators. LM MV treatment was accompanied by IκB-α degradation and NF-κB p65 nuclear translocation, whereas pharmacological inhibition of NF-κB attenuated macrophage activation. In a macrophage–melanoma co-culture system, LM MVs-activated macrophages reduced the viability, migration, and invasion of B16 melanoma cells and increased tumor cell apoptosis. Additional inhibition and immunofluorescence analyses suggested that iNOS and TNF-α-associated mechanisms contributed to these tumor-suppressive effects. In a murine melanoma model, LM MVs significantly inhibited tumor growth without overt systemic toxicity, whereas macrophage depletion markedly weakened this effect. These findings indicate that LM MVs exert antitumor activity against melanoma, at least in part through macrophage activation involving NF-κB signaling. Full article

Chronic low-grade inflammation, a key driver of diabetes and fatty liver disease, is present in obesity, which affects 2.1 billion adults as of 2021. Plant-derived bioactive peptides have emerged as promising alternatives to treat inflammation in these pathological processes. This study evaluated the effect of pre- and post-ultrasound-assisted enzymatic hydrolysis on bioactive peptide production and antioxidant activity from common bean (Phaseolus vulgaris L.) and pumpkin (Cucurbita argyoesperma) seed proteins. Pre-treated hydrolysates were fractionated by molecular weight (<3 kDa and 3–10 kDa) and evaluated for their anti-inflammatory properties by measuring nitric oxide and reactive oxygen species in three treatment schemes (pre-, co-, and post-treatment) in an obesity/inflammatory macrophage model. Ultrasound pre-treatment achieved a higher degree of hydrolysis (peptide production) compared to post-treatment, with corresponding increases in antioxidant activity as measured by the ABTS and ORAC assays. All hydrolysate fractions demonstrated dose-dependent inhibition of pro-inflammatory markers. Fractions administered as a co-treatment showed the strongest anti-inflammatory effect, reducing Nos-2 and Cox-2 mRNA expression, as well as secreted levels of pro-inflammatory cytokines (TNF-α, IL-6, MCP-1). These findings indicate that ultrasound treatment, mainly as pre-treatment, represents an effective strategy for producing bioactive peptide hydrolysates with anti-inflammatory properties in vitro that warrant deeper investigation. Full article

Mesenchymal stromal cells (MSCs) have shown immunomodulatory effects and great promise in many inflammatory diseases such as acute respiratory distress syndrome (ARDS). However, several barriers to translation remain such as cell availability and potency. This study evaluates the therapeutic potentials of three types of MSCs, bone marrow-derived MSCs (BM-MSC), the human induced pluripotent stem cell-derived MSC wild type (iMSC WT) and β2 microglobulin-knockout iMSCs (iMSC B2M KO) with or without proinflammatory cytokine preconditioning. BM-MSC, iMSC WT and iMSC B2M KO were preconditioned with a proinflammatory cytokine cocktail (Cytomix: IL-1β, IFN-γ and TNF-α). Immunoregulatory biomarkers were analysed by flow cytometry and cytokines released by ELISA. MSC antimicrobial properties were analysed via CFU assays while the MSCs’ immunomodulatory effects were evaluated using macrophage activation and T cell proliferation assays. Proinflammatory cytokine preconditioning enhanced the therapeutic potency of all three types of MSCs by increasing immunomodulatory marker expression, enhancing the antimicrobial effects and improving MSC-mediated inhibition of T cell proliferation. These findings provided new insights into the therapeutic potencies of MSCs in inflammation. Further studies are required for in vitro characterisation of the MSCs and in vivo efficacy verification of these MSCs prior to their clinical application. Full article

Globally, Mycobacterium tuberculosis (Mtb) remains the leading cause of death from a single infectious agent. The only licensed vaccine, Bacillus Calmette–Guérin (BCG), was developed over a century ago and does not provide consistent protection against pulmonary tuberculosis (TB). Efforts to develop more effective vaccines are hindered by an incomplete understanding of the correlates of protection and by the pathogen’s sophisticated immune-evasion strategies. Mtb systematically undermines host defenses, reprograms host cell biology, and interferes with cell–cell communication to establish a permissive niche and sustain chronic infection. An effective vaccine must elicit immune responses capable of overcoming these bacterial strategies across diverse host and pathogen backgrounds. Traditional approaches focused on boosting T cell responses have proven inadequate. In this review, we summarize innate and adaptive immune mechanisms that contain Mtb, examine how bacterial immune subversion and host–pathogen heterogeneity complicate vaccine design, and highlight emerging concepts and strategies to guide TB vaccine development. Full article

Although sorafenib (SOR) is effective for advanced hepatocellular carcinoma (HCC), significant metabolic heterogeneity limits its therapeutic effect. In this study, we employed high-resolution matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI MSI) to profile the spatial lipidomic alterations in 3D HepG2 spheroids following SOR treatment. Interestingly, sphingophospholipid and glycerophospholipid metabolism played crucial roles. In an orthotopic HCC mouse model, immunohistochemical and immunofluorescence staining confirmed that SOR induced immunological and inflammatory changes. Moreover, transcriptomic and Q-PCR analyses showed increased expression of Stat1, Zbp1, Parp14, Irf1, and Tifa along with decreased Eif4e2 in the SOR treatment group compared to the tumor control group. Bio-layer interferometry and molecular docking data also indicated that ZBP1 possessed favorable binding affinities with SOR. Overall, our findings demonstrated that SOR dramatically disrupted sphingolipid metabolism in tumor cell spheroids and, in an orthotopic model, activated the NOD-like receptor signaling pathway, accompanied by altered secretion of inflammatory factors and macrophage polarization. These results suggest that SOR exerts dual effects on tumor cell lipid metabolism and the tumor immune microenvironment. These findings provide a conceptual basis for future exploration of lipid-modulating therapeutic strategies in HCC. Full article

Metal homeostasis, which coordinates the influx and efflux of essential elements such as iron (Fe) and manganese (Mn) in chloroplasts, is essential for optimum photosynthesis, especially in metal-accumulating plants. Brassica juncea (Indian mustard) is a metal-tolerant species with a strong metal accumulation capacity, making it a suitable model for studying transition metal homeostasis. In this study, we identified two efflux transporters, BjYSL6.1 and BjYSL6.4, that localize in the endomembrane system of Schizosaccharomyces pombe and interact with the chloroplast Mn influx transporter BjNRAMP4.1 at the plasma membrane and within the chloroplasts. Bimolecular fluorescence complementation and split-ubiquitin yeast two-hybrid assays confirmed specific protein–protein interactions among these transporters, as well as with the membrane-bound thioredoxin BjHCF164, a known regulator of photosynthetic electron transport. Gene expression studies revealed that BjNRAMP4.1 and BjYSL6 isoforms are inversely regulated under Fe and Mn stress conditions, with BjNRAMP4.1 being strongly induced under deficiency, whereas BjYSL6.1 and BjYSL6.4 are downregulated. These findings suggest that a coordinated network involving BjNRAMP4.1, BjYSL6s, and BjHCF164 modulates metal influx and efflux at the chloroplast and plasma membrane interfaces, thereby maintaining metal homeostasis, which is critical for photosynthetic efficiency in B. juncea. Full article

The Hippo, as a central pathway regulating cell proliferation, apoptosis, stem cell homeostasis and organ development, is closely associated with the onset and progression of tumors, metabolic reprogramming, drug resistance and immune evasion when it is abnormally inactivated. The Hippo not only directly promotes tumor cell proliferation, maintains cancer stem cell properties, and mediates metabolic reprogramming and treatment resistance, but also reshapes the tumor microenvironment(TME) by regulating the formation, heterogeneity and function of cancer-associated fibroblasts (CAFs). Furthermore, it mediates tumor immunosuppression and immune evasion by modulating programmed death-ligand 1(PD-L1) expression, T-cell function, macrophage polarization and cytokine secretion. At the same time, inflammatory cytokines, growth factors, metabolites and physical signals within the TME can negatively regulate the activity of the Hippo, creating a pro-tumor positive feedback loop. This article provides a systematic review of the composition and regulation of the Hippo , its mechanisms of action in the biological behavior of tumor cells and interactions within the tumor microenvironment, as well as progress in the development of drugs targeting this pathway. It offers a theoretical basis for a deeper understanding of the role of the Hippo in tumors and for the development of novel anti-tumor therapeutic strategies. Full article

To date, we and others have demonstrated that GBA1-associated Parkinson’s disease (GBA1-PD) exhibits hyperactivation of mTOR and impairment of mTOR-regulated autophagy. Our previous study showed that the degree of autophagy impairment depends on the type of GBA1 mutation in peripheral blood mononuclear cell (PBMC)-derived macrophages. Moreover, the type of GBA1 mutation (“mild”—e.g., p.N370S or “severe”—e.g., p.L444P) correlates with PD severity and may influence therapeutic response. Here, we investigated the dose-dependent effects of GCase inhibition by conduritol β-epoxide (CBE) in SH-SY5Y cells on mTOR signaling, as well as the effects of mTOR inhibition by Torin 1 on mTOR-dependent autophagy-related proteins, lysosomal morphology, and lysosomal hydrolase activities in PBMC-derived macrophages from PD patients carrying GBA1-L444P or GBA1-N370S mutations. CBE induced dose-dependent activation of mTOR signaling in SH-SY5Y, as evidenced by dose-dependent accumulation of p-RPS6 (Ser235/236). mTOR inhibition decreased Beclin-1 protein levels while increasing the LC3B-II/LC3B-I ratio, LC3B–lysosome colocalization, and lysosome number regardless of mutation type in PBMC-derived macrophages. However, Torin1 reduced p62 levels in GBA1-N370S-PD, whereas lysosomal size decreased in GBA1-L444P-PD. Interestingly, Torin 1 increased GCase activity in both patient groups. These findings suggest that mTOR inhibition restores GCase function and autophagy and may represent a potential therapeutic strategy for GBA1-PD. Full article

Polybrominated diphenyl ethers (PBDEs), widely used as brominated flame retardants, are known to exert persistent adverse effects on the immune systems of humans and other organisms. Previous studies have demonstrated that 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47), a prevalent congener, induces apoptosis, impairs phagocytic function, and triggers aberrant immune-inflammatory reactions in RAW264.7 macrophages via the induction of elevated intracellular reactive oxygen species (ROS). However, the underlying regulatory mechanism remains unclear. The nuclear factor erythroid 2-related factor 2/antioxidant response element (Nrf2/ARE) signaling pathway is a key cellular defense system against oxidative stress. In this study, we investigated the role of the Nrf2/ARE pathway in BDE-47-induced macrophage immunotoxicity. Network toxicology analysis identified Nrf2 as a hub gene within the BDE-47-associated immunotoxicity network. Molecular docking and molecular dynamics simulations suggested a potential interaction between BDE-47 and the Keap1-Nrf2 complex, with moderate binding affinity. Experimental studies in RAW264.7 cells showed that BDE-47 exposure activated the Nrf2/ARE pathway, as evidenced by Nrf2 nuclear translocation and the differential upregulation of downstream genes (GCLC, GCLM, HO-1, NQO1, SOD1, and CAT). Importantly, Nrf2 knockdown via lentiviral shRNA or pharmacological inhibition with brusatol significantly exacerbated BDE-47-induced apoptosis and immune dysfunction, including enhanced pro-inflammatory cytokine production and impaired phagocytosis. These results demonstrate that Nrf2/ARE pathway activation represents an adaptive antioxidant response and contributes to limiting BDE-47-induced cytotoxicity and immune impairment in macrophages. Full article

Class B scavenger receptor BI splice variants (SR-BI) and BII (SR-BII) internalize lipoproteins but also bind and internalize bacteria. Their individual roles in sepsis are unknown. We overexpressed human SR-BI or BII in transgenic mice, primarily in the liver, but also in the kidney and in bone marrow-derived macrophages, and then performed cecal ligation and puncture (CLP) surgery. SR-BI and BII transgenic mice had significantly worse survival compared to WT mice. Twenty-four hours after CLP, liver injury markers and histological damage were elevated in both SR-BI and BII transgenic mice, whereas kidney damage was similar. Systemic inflammatory cytokines were markedly increased in SR-BI and BII transgenic mice; parallel increases were seen in liver mRNA expression, but not in the kidney. The highest degree of neutrophil infiltration was observed in the liver of SR-BI. Human SR-BI and BII dramatically decreased bacterial accumulation in the liver. Green fluorescent protein-labeled E. coli were efficiently phagocytosed in hepatic macrophages of SR-BI and BII transgenic mice; phagocytosis was more prominent in SR-BII transgenic mice. Finally, human SR-BI overexpression reduced systemic HDL-C levels, eliminated adrenal cortex lipid droplets, and dampened the systemic increase of corticosterone after CLP. Supplementation with glucocorticoid and mineralocorticoid improved survival in SR-BI but not in SR-BII transgenic mice after CLP. In summary, our findings suggest human SR-BI and BII overexpression contributes to higher mortality after CLP by different mechanisms: excessive inflammatory response due to adrenal insufficiency (SR-BI) or hyperactive phagocytosis (SR-BII) in the liver. Full article

Type II toxin–antitoxin (TA) systems are significantly expanded in the Mycobacterium tuberculosis complex; however, the functional role of the VapBC40 system in Mycobacterium bovis(M. bovis) pathogenesis remains poorly characterized. This study aimed to investigate the role of VapBC40 in mycobacterial virulence and evaluate its potential as a target for rational vaccine attenuation. We performed evolutionary analysis and yeast two-hybrid assays to characterize VapBC40 system specificity, conducted in vitro macrophage infection models and in vivo murine studies to assess virulence contribution, and evaluated the immunoprotective efficacy of a VapC40 knockout strain. Evolutionary analysis revealed progressive sequence conservation and stringent homologous pairing specificity within the VapBC40 system. The VapC40 toxin correlates with enhanced intracellular bacterial survival, increased host cell death, and more severe pulmonary pathology with systemic dissemination. Based on these findings, we evaluated the vaccine potential of a vapC40 knockout strain. Immunization with this attenuated strain elicited a Th1 cellular immune response, characterized by enhanced IFN-γ production and increased frequency of CD4⁺IFN-γ⁺ T cells. Upon challenge with virulent M. bovis, the knockout strain conferred superior protection compared to the conventional BCG vaccine, significantly reducing lung pathology and restricting extrapulmonary bacterial dissemination. Although the molecular mechanisms underlying VapC40-mediated effects remain to be fully elucidated, our findings suggest an important role of the VapBC40 system in mycobacterial-host interactions and support its potential as a target for next-generation tuberculosis vaccine development. Full article

Trauma-induced heterotopic ossification (tHO) is characterized by aberrant ectopic bone formation in soft tissue following high-energy trauma, affecting >60% of combat-related amputees and >50% of major burn patients. Current prophylactic strategies (including NSAIDs, bisphosphonates, and low-dose radiation) lack mechanistic specificity, carry significant side effects, and surgical excision carries a 27% recurrence rate. This review reframes tHO pathogenesis through the neural–immune axis, arguing that ectopic bone formation is a downstream consequence of dysregulated neuroimmune signaling rather than a primary osteogenic event. Following trauma, nociceptor activation drives nociception-induced neural inflammation (NINI), releasing substance P (SP) and calcitonin gene-related peptide (CGRP), which disrupts the blood–nerve barrier, mobilizes neural crest-derived progenitor cells, and, alongside BMP-2/SMAD1/5/8 signaling and M1-polarized macrophage activation, establishes a permissive osteogenic microenvironment. A BMP-2/CGRP positive feedback loop sustains aberrant osteogenesis, converging on osteogenic transcription factors Runx2, SOX5/6/9, and Osterix. Dysregulated noncoding RNAs represent promising pre-radiographic biomarkers. This neural–immune framework motivates mechanism-based therapeutic strategies targeting CGRP (fremanezumab, erenumab), SP/NK1 signaling (aprepitant), and macrophage polarization (metformin, palovarotene, rapamycin), with multi-node combination approaches tailored to the temporal stages of tHO offering the most promise for precision prophylaxis. Full article

Background: Macrophage migration inhibitory factor (MIF) is a critical modulator of the tumor immune microenvironment (TME). Its clinical significance in head and neck squamous cell carcinoma (HNSCC) remains controversial because of HPV-dependent tumor biology and the limitations of single-timepoint biomarker assessments. This preliminary study evaluates whether dynamic changes in circulating MIF (ΔMIF) in an HPV-stratified longitudinal cohort reflect disease severity and treatment response. Methods: Ninety-six serial serum samples were analyzed from 27 HNSCC patients (22 HPV-positive, 5 HPV-negative) from diagnosis through therapy and follow-up. Serum MIF and anti-HPV16 E7 IgG were quantified by ELISA, and ΔMIF was defined as the change in MIF concentration between consecutive visits. Results: Baseline MIF did not correlate with clinical stage in the total cohort (p = 0.63). However, 56% of HPV-positive patients exhibited a positive correlation between elevated MIF and advanced stage. Following chemoradiotherapy, the HPV-negative group showed a consistent and significant decline in MIF (mean ΔMIF = −1.23, p = 0.031), corresponding with no evidence of disease (NED). In contrast, the HPV-positive group showed heterogeneous trajectories (mean ΔMIF = +0.21, p = 0.94), with several patients demonstrating paradoxical declines in MIF during active disease or relapse, followed by recovery upon reaching NED. In select cases, MIF dynamics were closely synchronized with anti-E7 IgG levels. Conclusions: Serum MIF dynamics are strongly dependent on HPV status. While MIF serves as a reliable therapy-monitoring marker in HPV-negative HNSCC, it may play a complex and paradoxical immunomodulatory role in HPV-positive disease. These preliminary findings support the need for larger prospective, HPV-stratified trials. Full article