Search Results (7,907)

Cytotoxic CD8 T lymphocytes are crucial in antiviral immune responses. However, their recruitment to infection sites renders them at risk of viral infection, which could affect their effector activity. CD8 T lymphocytes express RIG-I, which detects cytosolic viral RNA and subsequently induces antiviral gene expression. We investigated how Influenza A virus infection and synthetic triphosphorylated double-stranded RNA, a specific RIG-I ligand, influence TCR-dependent effector responses in primary human CD8 T cells. Cells were isolated from healthy donors and either infected with the reassortant virus RG-PR8-Brazil78 (H1N1) or transfected with the synthetic RNA. Proliferation, degranulation, and cytokine production upon anti-CD3/CD28 stimulation were assessed using flow cytometry and intracellular cytokine staining. Type I IFN production and downstream signaling were measured using IFN-I reporter assay and Western blotting. CRISPR/Cas9 gene editing was employed to knock out RIG-I and STAT2 to evaluate their roles in antiviral responses. Influenza A virus infection of CD8 T cells stimulated RIG-I and activated downstream pathways, including TBK1 and NF-κB, resulting in type-I interferon secretion. Transfection of cytotoxic CD8 T lymphocytes with synthetic RIG-I ligands not only stimulated these pathways but also enhanced the proliferation of CD8 T cells in vitro and protected them from influenza A virus infection. In line with a positive effect on CD8 effector function, both influenza A virus infection and RIG-I ligand transfection enhanced CD8 T cell degranulation and cytokine secretion. Conversely, activation of CD8 T lymphocytes via CD3/CD28 crosslinking increased their susceptibility to influenza A virus infection. We demonstrated that RIG-I stimulation by virus infection or RIG-I ligand transfection promotes intrinsic antiviral pathways and enhances CD8 T-cell effector functions and proliferation. This suggests that RIG-I agonists could enhance and prolong the effector function of cytotoxic CD8 T lymphocytes in immunotherapy. Full article

Water-soluble fullerene derivatives such as fullerenol C₆₀(OH)₂₄ are promising candidates for nanomedicine applications, yet their effects on innate immune cells remain poorly characterized. We investigated the interaction of fullerenol with human neutrophils isolated from healthy donors, exposed to concentrations of 0.25–200 μg/mL over 24–72 h. Using multi-parameter flow cytometry, we assessed viability, apoptosis, phagocytic activity, and intracellular reactive oxygen species (ROS) production, complemented by cell-free DPPH radical scavenging assays. Fullerenol was taken up by neutrophils in a concentration- and time-dependent manner. No significant cytotoxicity was observed up to 100 μg/mL, while viability declined at 200 μg/mL. Phagocytosis of opsonized E. coli was preserved at lower concentrations, though a statistically significant negative correlation with fullerenol concentration was detected at higher doses. In cell-free assays, fullerenol scavenged DPPH radicals with an EC₅₀ of 48.90 ± 10.02 μg/mL, exhibiting slower kinetics than Trolox or ascorbic acid. Critically, fullerenol suppressed intracellular ROS production by >33% at 50 μg/mL following PMA stimulation of neutrophils. These findings demonstrate that fullerenol C₆₀(OH)₂₄ combines potent intracellular antioxidant activity with a favorable neutrophil safety profile, supporting its potential application in oxidative stress-related conditions. Full article

Bovine viral diarrhea virus (BVDV), a globally persistent pathogen, causes bovine viral diarrhea-mucosal disease (BVD-MD), a contagious bovine disease posing significant pressures on both public health and economic development. Baicalin (BA), a flavonoid derived from Scutellaria baicalensis, exhibits broad antiviral activities but suffers from poor aqueous solubility and low bioavailability, limiting its therapeutic potential against BVDV. To address this limitation, we developed BA-loaded poly (ethylene gly-col)-poly (lactic-co-glycolic acid) (PEG-PLGA) nanoparticles (BA-PEG-PLGA NPs). While autophagy and NLRP3 inflammasome activation have been individually implicated in viral pathogenesis, their functional crosstalk during BVDV infection remains uncharacterized. Herein, we evaluated the antiviral efficacy of BA-PEG-PLGA NPs through integrated in vitro and in vivo experiments. We employed quantitative polymerase chain reaction (qPCR), transcriptome sequencing, Western blot analysis, immunofluorescence microscopy, flow cytometry, and enzyme-linked immunosorbent assay (ELISA) to investigate the mechanisms by which BA and BA-PEG-PLGA NPs combat bovine viral diarrhea virus (BVDV) infection. We found that both free BA and BA-PEG-PLGA NPs effectively attenuated BVDV replication in vitro and in vivo; notably, the nano-formulation exhibited superior efficacy. Mechanistically, BA and its nano-formulation restored autophagy homeostasis, suppressed ROS overproduction, and blocked NLRP3 inflammasome activation and pyroptotic cell death effects comparable to the specific NLRP3 inhibitor MCC950. These findings establish the autophagy–NLRP3/pyroptosis axis as a critical pathogenic mechanism in BVDV infection and reveal that nano-formulated baicalin represents an antiviral strategy by coordinately targeting this axis. This work not only provides a translatable nanomedicine approach for BVDV control but also expands the mechanistic understanding of flavonoid-based interventions in viral inflammatory diseases. Full article

Viral infections with gastrointestinal involvement remain a significant global health burden with limited therapeutic options. While probiotics show antiviral potential, their impact on primary human intestinal epithelial defenses is poorly defined. This study utilized human intestinal organoid-derived monolayers (ODMs), generated from the non-inflamed mucosa of patients with inflammatory bowel disease, to examine how Bifidobacterium animalis ssp. lactis BB-12 (BB-12) and Lacticaseibacillus rhamnosus GG (LGG) modulate mucosal antiviral pathways. Unlike conventional Caco-2 cells, ODMs preserved physiological cellular diversity and intact innate signaling. Expression of viral receptors and interferon (IFN)-stimulated genes (ISGs) was quantified by RT-qPCR, while the effector 2′-5′-oligoadenylate synthetase 1 (OAS1) was also assessed by immunofluorescence and flow cytometry. Both probiotic strains modulated IFN-associated pathways; however, BB-12 induced a markedly stronger antiviral transcriptional response than LGG. Notably, OAS1 exhibited cell type-specific regulation; while goblet cells showed high basal levels, both probiotics enhanced OAS1 expression selectively in ileal enterocytes. Despite this shared effect, only BB-12 pretreatment significantly restricted Influenza A (H1N1) replication in ileal ODMs, whereas LGG did not significantly affect viral replication. These findings establish human ODMs as a superior platform for probiotic immunology, suggesting that BB-12 more effectively shapes epithelial antiviral “set-points” and highlighting OAS1 as a sensitive component of a broader antiviral program. Full article

Protein-losing enteropathy (PLE) is an uncommon and often underrecognized manifestation of lymphoproliferative disorders and may be difficult to diagnose when conventional gastrointestinal investigations are unrevealing. We present an 82-year-old woman with recurrent hospital admissions initially spanning six months for diarrhea, weight loss, peripheral edema, and persistent hypoalbuminemia. Initial upper gastrointestinal endoscopy was normal, and colonoscopy was deferred due to intercurrent infection. Despite extensive laboratory and radiologic evaluation, including routine biochemical testing and imaging, the etiology of PLE remained unclear. Peripheral blood flow cytometry subsequently identified a small kappa-restricted monoclonal B-cell population compatible with marginal zone lymphoma, later confirmed on bone marrow biopsy, raising suspicion for gastrointestinal involvement. Video capsule enteroscopy demonstrated diffuse erosive and ulcerative disease throughout the small intestine, providing an anatomical explanation for the patient’s protein loss. Following lymphoma-directed therapy, repeat capsule enteroscopy showed complete normalization of the small bowel mucosa. This case highlights the diagnostic value of combining peripheral blood flow cytometry and capsule endoscopy in unexplained protein-losing enteropathy, a rare and diagnostically challenging presentation of indolent lymphoma, and illustrates the role of capsule imaging in both disease localization and treatment monitoring. As a single-case report, these findings are not generalizable, and further studies are required to evaluate the broader applicability of this diagnostic approach. Full article

Background: Despite its high vaccination coverage, pertussis remains a public health concern due to waning vaccine-induced immunity and the emergence of pertactin (Prn)-negative strains. Nevertheless, anti-Prn antibodies and memory B cells elicited by vaccinations may contribute to long-term immunity and protection against Prn-positive strains. While most vaccination studies focus on serum antibodies, data on memory B cells remain limited. Methods: In this study, we implemented a flow cytometry-based approach to characterize Prn-specific B-cell fluctuations following Tdap booster vaccination in five healthy adults. Total and Prn- and tetanus toxoid fragment C (TTC)-specific plasma cells and memory B cells were analyzed at baseline and at 7, 14, 21, and 90 days post-vaccination using Prn Klickmers^® and TTC tetramers. Following this, cellular responses were correlated with antigen-specific serum IgG and IgA levels. Results: Prn-specific and TTC-specific memory B cells increased on days 14 and 7 post-vaccination, respectively, accompanied by a phenotypic shift from IgMD+ to IgG+ cells. Clear expansions of total as well as Prn- and TTC-specific plasma cells occurred on day 7. These plasma cells primarily comprised IgG+, but an increase in Prn-specific IgA+ plasma cells was also observed. The numbers of Prn-specific IgG+ memory B cells on day 7 post-vaccination correlated weakly with serum anti-Prn IgG levels at later time points. Conclusion: To our knowledge, this is the first study to use flow cytometry to evaluate Prn-specific B-cell responses and report their fluctuations over time following vaccination. These findings support the potential of this method to complement serological assays and improve our understanding of vaccine-induced immunity. Full article

Background: In an earlier murine model of myocardial infarction (MI), we showed that CD8 cells and myeloid dendritic cells (mDCs) infiltrate the infarcted myocardium within the first week. However, in humans, the spatial interplay between CD8⁺ T cells and dendritic cells in the spatial context of human myocardial infarction remains underexplored. Objective: In the present study, we applied spatial transcriptomics and functional assays to characterize immune–stromal dynamics in infarcted myocardium and peripheral blood. Methods & Results: Spatial transcriptomics analysis of infarcted human myocardium at days 2 and 6 post-MI, combined with peripheral blood flow cytometry and EPC colony-forming assays, was performed. Cell composition, pathway enrichment, and cell-to-cell communication analyses were conducted to map immune–stromal cells’ dynamics across time points. Spatial mapping identified dynamic shifts in immune, fibroblast, and endothelial populations, with fibroblasts and endothelial cells remaining abundant throughout. CD8⁺ T cells accumulated in ischemic regions while their circulating levels declined. Gene Ontology and pathway analyses of CD8A⁺ transcripts revealed enrichment of proinflammatory and NF-κB survival programs. ITGAX/CD33/THBD⁺ APCs progressively increased within infarct zones, activating antigen-presentation and leukocyte chemotaxis pathways. Early (day 2) APC–endothelial crosstalk showed the strongest predicted recruitment signals for CD8⁺ T cells, which diminished by day 6. Finally, EPC colony-forming capacity showed a tendency for reduction in MI patients and inversely correlated with coronary lesion burden, indicating impaired vascular repair potential. Conclusions: This integrative spatial and functional study demonstrates that APC-driven CD8⁺ recruitment and EPC dysfunction are key features of human MI. Immune–endothelial niches facilitate early cytotoxic T-cell infiltration, while progenitor depletion limits vascular regeneration. These findings provide mechanistic insight into immune–vascular imbalance during infarct healing and highlight potential therapeutic targets to modulate inflammation and restore vascular repair. Full article

WD repeat and HMG-box DNA-binding protein 1 (WDHD1) has been identified as a crucial oncogene in various tumors, but its role in pancreatic cancer remains unexplored. This study investigated the mechanisms by which WDHD1 contributes to pancreatic cancer progression. Differential analysis of the Cancer Genome Atlas (TCGA) pancreatic cancer samples identified abnormally expressed genes. Cellular assays, including cell proliferation, flow cytometry, and apoptosis assays, demonstrated WDHD1’s oncogenic role. WDHD1 expression was significantly elevated in pancreatic cancer cells and tissues compared to normal counterparts. Knockdown of WDHD1 inhibited cell proliferation, induced apoptosis, and caused G1-phase cell-cycle arrest. In vivo xenograft models further validated that WDHD1 knockdown suppressed the growth of pancreatic cancer cells. Mechanistically, WDHD1 knockdown resulted in significant reductions in CDK4 and cyclin D1 protein levels, whereas WDHD1 overexpression produced the opposite effects. Additionally, E2F1 overexpression increased the expression of WDHD1 at both mRNA and protein levels. Rescue experiments revealed that WDHD1 knockdown could reverse the E2F1-induced upregulation of CDK4 and cyclin D1 protein levels. In conclusion, E2F1 promotes pancreatic cancer cell proliferation and cell-cycle progression by upregulating WDHD1, which in turn enhances the expression of the CDK4–cyclin D1 complex. Full article

Background: The aminosteroid RM-581 exhibits strong antiproliferative activity against cell lines from more than 10 solid tumor cancers, including some with poor prognoses. However, RM-581’s impact has never been assessed on leukemia. Methods: Cellular responses to RM-581 were evaluated using complementary approaches. Cytotoxicity was quantified using MTS-based viability assays and drug interactions were analyzed according to the Chou-Talalay method. Flow cytometry was employed to assess apoptosis, cell cycle distribution and effects on lymphocytes subpopulations. The transcriptomic profile was investigated by mRNA sequencing to identify differentially expressed genes and associated pathways. Results: Its evaluation on six leukemia cell lines (HL-60, THP-1, JURKAT, K-562, HG-3 and JVM-2) showed that RM-581 efficiently blocked the proliferation of leukemia cells. In healthy peripheral blood lymphocytes, flow cytometry revealed a significant impact on T lymphocytes (CD3+), particularly cytotoxic T cells (CD8+), at 50 µM. In THP-1 cells, an acute monocytic leukemia cell line, RM-581 triggered apoptosis and induced G0/G1 cell cycle arrest, which was confirmed with a transcriptomic analysis of enriched pathways. The role of RM-581 as an endoplasmic reticulum (ER) stress aggravator was confirmed by observing an increase in ER stress markers, such as BIP (GRP-78), CHOP and HERP, and in unfolded protein response (UPR) effectors (PERK, IRE1α and ATF6). Conclusions: This study demonstrates that RM-581 could be a promising candidate to treat leukemia, notably through the induction of ER-stress mediated apoptosis. Full article

Background/Objectives: BRAF and/or MEK inhibitors are widely used for patients with BRAF-mutated melanoma, but no biomarkers of response or resistance are currently available. Besides adverse events in different organs, target therapy with BRAF and/or MEK inhibitors may induce the onset of immune-related adverse events (irAEs) that have been considered as possible biomarkers of good prognosis in patients with melanoma. Methods: To investigate this aspect, we analyzed the occurrence of irAEs in a cohort of 158 patients treated with BRAF and MEK inhibitors. We also analyzed by flow cytometry the subsets of circulating immune cells in the patients who developed irAEs and matched controls. Results: We found that irAEs occurred in 3 out of 101 patients (3%) who experienced adverse events. These three patients did not exhibit any specific clinical features or circulating immune cell subtypes that could be associated with a positive response to treatment. However, the onset of toxicity in the entire patient cohort was associated with longer progression-free survival. Notably, the frequency of circulating follicular helper T cells increased in all examined patients during the first two months of treatment. Conclusions: The small sample size prevents us from determining whether irAEs are effectively caused by BRAF/MEK inhibitors or if they are a random event. Additionally, we cannot conclude whether irAEs are related to a better outcome. Nevertheless, we note that BRAF/MEK inhibition may alter the composition of circulating immune cells in melanoma patients. This aspect should be investigated further before proposing combinations of target therapies and immunotherapies. Full article

With the rising prevalence of feline kidney diseases, effective preventive and therapeutic strategies are urgently needed. This study evaluated the effects of Cybister chinensis extracts (CCME) and Periplaneta americana residue extracts (PAE) on inflammation-associated, oxidative stress-related, and fibrosis-related responses in Crandell-Rees Feline Kidney (CRFK) cells. Using MTT assays, flow cytometry, and qPCR, we assessed cytoprotection in models of lipopolysaccharide (LPS)-, hydrogen peroxide (H₂O₂)-, and palmitic acid (PA)-induced injury. Preliminary HPLC fingerprint analysis of three batches of a combined extract from Periplaneta americana residues and Cybister chinensis Motschulsky (CPCE) revealed similar chromatographic profiles, indicating good batch-to-batch consistency. Within non-cytotoxic ranges, CPCE increased cell viability and reduced apoptosis in injured CRFK cells. Anti-inflammatory effects were evidenced by significant downregulation of TNF-α and IL-6 mRNA. Potential antioxidant-related effects were suggested by decreased expression of oxidative stress–responsive genes SOD1, CAT, and GSTP1. In the PA model, anti-fibrotic potential was supported by reduced TGFB1 expression, accompanied by improvements in inflammatory and oxidative stress markers, and by decreased levels of fibrosis-associated markers α-SMA, COL I, and HCB III. These findings suggest that CPCE exerts cytoprotective effects in vitro, potentially through modulation of inflammation, oxidative stress, and fibrosis. Full article

Sperm cryopreservation is pivotal for conserving fish germplasm, yet cryodamage-induced quality decline limits its application. This study focused on Sichuan bream (Sinibrama taeniatus), an endemic and economically important fish species in the upper Yangtze River. Based on an established cryopreservation protocol, we evaluated sperm quality using computer-assisted sperm analysis (CASA) and fertility assays, followed by a systematic assessment of structural and functional damage via flow cytometry (membrane integrity, mitochondrial potential, reactive oxygen species, and DNA fragmentation), enzymatic assays (energy metabolism and antioxidant enzymes), Western blotting, and ultrastructural observation. Finally, integrated proteomic and metabolomic analyses were employed to elucidate the underlying physiological mechanisms. The results demonstrated that freeze–thawing significantly impaired sperm motility, fertility, and ultrastructure, concurrently disrupting energy metabolism and the antioxidant system. Crucially, multi-omics revealed that these functional declines were linked to dysregulation in key pathways involving cytoskeleton organization, lipid metabolism, energy homeostasis, and oxidative stress, forming a coherent network from initial molecular perturbation to phenotypic dysfunction. This study provides a comprehensive characterization of sperm cryodamage in Sichuan bream, advancing the understanding of fish sperm cryobiology and informing targeted cryoprotection strategy development. Full article

Background/Objectives: Glioblastoma multiforme (GBM) is the most infiltrative, treatment-resistant, and deadly brain tumor in adults. Given the extremely malignant phenotype of the GBM cells, the high intratumoral heterogeneity, and the limited efficacy of the vast majority of chemotherapeutics due to the restrictive nature of the blood–brain barrier, GBM remains largely incurable. Methods: Utilizing the U87, U251, and T98G GBM cell lines, diverse in vitro approaches (Western blotting, quantitative real-time PCR, flow cytometry, immunofluorescence, Luc-reporter analysis, microscopic examination, and scanning electron microscopy), and pharmacological inhibition, we investigated for the first time the cell death decisions in the GBM cells in response to the LCS1269 treatment. Results: We showed that LCS1269 collapsed the mitochondrial potential and triggered both intrinsic and extrinsic apoptosis. Importantly, our findings demonstrated that LCS1269-mediated apoptosis was paralleled by an induction of both MLKL-dependent necroptosis and caspase-3/GSDME-dependent pyroptosis. Using a combination of specific inhibitors, we further demonstrated that apoptosis, necroptosis, and pyroptosis provoked by LCS1269 occur simultaneously and orchestrate a peculiar form of programmed cell death, which is known as PANoptosis. We subsequently found that LCS1269-induced PANoptosis may be initiated either through the RIPK1-PANoptosome alone or through the integrated ZBP1-, AIM2-, and RIPK1-PANoptosomes. Additionally, we revealed that LCS1269-mediated PANoptosis may be closely related to micronuclei formation. Conclusions: Taken together, our results confirm that LCS1269 is a promising anti-glioblastoma agent that is capable of effectively promoting GBM cell death via PANoptosis. Full article

Background: Tumor cells can reprogram their metabolism, constituting a hallmark of cancer that plays a crucial role in tumor progression. As tumor cells exhibit an increased demand for nutrients, e.g., amino acids, they rely on extracellular sources and show deregulation of transport proteins. Among these, SNAT1 (SLC38A1) is described as the loader for glutamine that is responsible for the main influx of this amino acid. The aim of this study was to assess the molecular function of SNAT1 in melanoma regarding its role in amino acid transport and regulation of cellular metabolism. Methods: siPool-mediated downregulation of SNAT1 expression in melanoma cell lines was used to investigate the molecular function of this protein. Glutamine transport was assessed by measuring the intracellular and extracellular concentrations of glutamine. Regulation of downstream effectors was evaluated with qRT-PCR and Western Blot. Metabolism was investigated by performing Seahorse flux analysis. Mitochondrial staining was examined via flow cytometry. Protein interaction was assessed with Co-IP, and in silico modeling of protein interaction was performed with AlphaFold3. Results: In this study, we uncovered the new finding that SNAT1 is not primarily implicated in glutamine influx into melanoma cells but in signaling in response to extracellular glutamine. We identified P62 and cMYC as downstream effectors of SNAT1. By activating the P62/cMYC-axis and target genes of cMYC, SNAT1 modulates the metabolism of melanoma cells depending on the glutamine level. SNAT1 and P62 are interaction partners. Conclusions: This finding newly suggests that SNAT1 may function as a sensor or receptor (“transceptor”) for glutamine rather than being a direct and primary glutamine transporter, and could open up new therapeutic options targeting melanoma cells. Full article

Chronic kidney disease (CKD) involves uremic toxin-driven tubular injury and systemic vascular dysfunction, in which mitochondrial impairment and apoptotic cell loss contribute to progressive tissue deterioration. Accordingly, a targeted EV platform is required to enable efficient miRNA delivery to the toxin-stressed tubular–endothelial compartment. Based on our previous study showing that melatonin restores miR-4516 levels under CKD-related stress, we directly loaded miR-4516 into engineered extracellular vesicles (EVs) to evaluate its effects on mitochondrial function and cell survival. Here, we engineered EVs with a G3-C12/RGD surface modification and established a miR-4516 loading strategy to enhance delivery to kidney proximal tubule cells and vascular endothelial cells. miR-4516 loading increased EV-associated miR-4516 levels without major changes in particle size distribution, and EV identity was supported by CD9 and CD81 expression. Confocal microscopy and flow cytometry demonstrated increased cellular uptake of miR-4516-loaded G3-C12/RGD-EVs compared with control EVs in TH1 proximal tubule cells and HUVECs. Under indoxyl sulfate stress, engineered EV treatment restored intracellular miR-4516 and improved mitochondrial function, as indicated by recovery of respiratory Complex I and Complex IV activities and improved Seahorse bioenergetic parameters (OCR/ECAR, basal and maximal respiration, ATP-linked respiration, and spare respiratory capacity). Annexin V staining further indicated reduced toxin-induced apoptosis. In an adenine diet-induced CKD mouse model, intravenous administration of miR-4516-loaded G3-C12/RGD-EVs improved urinary albumin-to-creatinine ratio (UACR), blood urea nitrogen (BUN), and serum creatinine. These findings indicate that miR-4516-loaded, targeting-engineered EVs may mitigate uremic toxin-associated mitochondrial dysfunction and renal impairment in CKD. Full article