Search Results (6,992)

Background: Diabetic retinopathy (DR), a leading cause of blindness, lacks early biomarkers and mechanism-targeted therapies. While oxidative stress drives DR pathogenesis, the role of oxeiptosis—a reactive oxygen species-induced, caspase-independent cell death pathway—remains largely unexplored. Methods: We integrated transcriptomic profiling (GSE221521: 69 DR vs. 50 controls), two-sample Mendelian randomization (MR) using blood cis-eQTLs (GTEx) as instruments and DR GWAS (FinnGen R12) as outcome, machine learning-based feature selection (SVM-RFE and Boruta algorithms), and single-cell RNA sequencing (scRNA-seq) analysis (GSE165784). Functional enrichment, immune deconvolution (CIBERSORT), and diagnostic nomogram construction were performed. We validated the key genes using human retinal microvascular endothelial cells (hRMECs) treated with high glucose (30 mM). Results: Oxeiptosis scores were elevated in DR blood samples (p < 0.001). MR analysis identified five putative causal genes: CASP2 (OR = 1.067), PLEC (OR = 1.035) and FBN2 (OR = 1.016) as risk factors, and CYP27A1 (OR = 0.960) and GPD2 (OR = 0.958) as protective factors. SVM-RFE and Boruta algorithms confirmed CASP2 and PLEC as hub genes. A nomogram incorporating both genes achieved robust DR prediction (AUC = 0.811). Functional analysis associated these genes with innate immune activation and extracellular matrix reorganization. Single-cell transcriptomics revealed PLEC was markedly overexpressed in disease-relevant cells (fibroblasts, endothelial cells), whereas CASP2 exhibited a distinct pattern, with notable enrichment in retinal CD8+ T cells. Both genes were associated with a pro-inflammatory shift in the immune landscape. Their upregulation was validated in independent datasets and high-glucose-stressed retinal cells. Conclusions: This study establishes an integrated multi-omics framework implicating oxeiptosis-related pathways in DR and nominates CASP2 and PLEC as putatively causal, biologically relevant candidate biomarkers and potential therapeutic targets. Full article

Background: Inflammation plays a central role in the formation of peptic ulcers, yet the contribution of cellular immunity remains poorly defined. This study aimed to clarify the contribution of cellular immunity to acute gastric mucosal injury. Methods: BALB/c mice received 80% ethanol via oral gavage to induce acute gastric injury. Stomachs were examined macroscopically and histologically, and gastric tissues were analyzed by qPCR, ELISA, and flow cytometry for cytokine expression, immune cell infiltration, and apoptosis. Results: Administration of ethanol exacerbated acute gastric injury in mice, as evidenced by extensive macroscopic lesions and severe disruption of mucosal architecture. This damage was accompanied by marked infiltration of CD11c⁺ dendritic cells, together with an increased frequency of CD86-expressing and IL-12-producing dendritic cells. In addition, there was greater accumulation of both CD4⁺ and CD8⁺ T lymphocytes, including elevated numbers of CD4⁺ and CD8⁺ cells producing IFN-γ and IL-17, as well as CD8⁺CD107a⁺ cytotoxic cells. Alongside these cellular alterations, ethanol exposure was accompanied by elevated levels of pro-inflammatory cytokines (IL-1β, TNF-α, IL-17, and IFN-γ) in gastric tissue. In parallel, ethanol exposure also promoted epithelial cell apoptosis, further contributing to mucosal deterioration. Conclusions: Our findings reveal for the first time that both CD4⁺ and CD8⁺ T cells participate in sterile ethanol-induced acute gastric injury, emphasizing cellular immunity as an important yet insufficiently studied contributor to mucosal damage and highlighting the necessity for further mechanistic and translational research. Full article

Chlamydia trachomatis infection causes pelvic inflammatory disease and infertility, but how host immune factors control pathogen clearance or pathology is not fully understood. Using a mouse model of genital tract infection with Chlamydia muridarum, we examined the role of CD1d-restricted Natural killer T (NKT) cells. Invariant NKT cell-deficient mice (Jα18^−/−) showed prolonged vaginal shedding of infectious elementary bodies (EBs), delayed clearance, and decreased early cytokine production compared to wild-type (WT) controls. Conversely, CD1d^−/− mice, which lack both invariant and diverse NKT cells, did not show significant differences in vaginal shedding compared to WT mice. Surprisingly, both NKT-deficient mice (Jα18^−/− and CD1d^−/−) produced higher levels of inflammatory cytokines in the oviduct at day 35 post-infection (p.i.) and experienced more frequent upper genital tract pathology (hydrosalpinx) at day 80 p.i. However, no infectious EBs were recovered from the oviducts or uterine horns of NKT-deficient mice after day 35 p.i. Cortisone acetate reactivated infectious shedding in chronically infected NKT-deficient mice at day 100 p.i. These findings highlight distinct roles for NKT cell subsets: invariant NKT cells promote early clearance via rapid cytokine production, while the broader NKT population helps limit tissue damage. Targeting NKT pathways could help prevent chronic infection and infertility. Full article

Background/Objectives: Circulating tumor cells (CTCs) and large extracellular vesicles (LEVs) are key components of the liquid biopsy that provide minimally invasive access to tumor biology. A clinically relevant subset of CTCs coexpressing epithelial and immune markers (im.CTCs) has been described, yet the origin of this phenotype remains unclear. In this study, we investigated the cellular and molecular context underlying the emergence of immune marker expression on CTCs and LEVs. Methods: Using high-resolution immunofluorescence microscopy of patient-derived blood samples, we identified direct physical interactions between white blood cells (WBCs) and both im.CTCs and im.LEVs, exclusively in patients harboring im.CTCs. Results: In several cases, WBCs partially encapsulated CTCs and LEVs, and quantitative analysis revealed localized enrichment of immune membrane markers at the contact interface, distinguishing these events from random proximity. Proteomic profiling further identified CD4+ T cells as the predominant interacting immune cell type and confirmed the presence of CD45, CD3, and CD4 on the interacting CTCs and LEVs, matching their WBC counterparts. Conclusion: These findings support membrane transfer as a potential mechanism for the acquisition of immune markers by CTCs and LEVs and provide in vivo evidence of contact-dependent tumor-immune interactions in circulation with implications for immune modulation and clinical interpretation of the im.CTC phenotype. Full article

Objectives: Shengji Yuhong Ointment (SJYHO) is a classic Traditional Chinese Medicine prescription used for refractory wounds, yet its systemic pharmacological mechanisms remain unclear. This study aimed to identify its key active compounds and develop a simplified, effective topical formulation. Methods: We employed an integrated approach, combining network pharmacology and machine learning to screen the key constituents and core targets of SJYHO. The lead compound, glycyrrhizic acid, was formulated into a hydrogel (GA-Gel). Its therapeutic efficacy was evaluated in a full-thickness excisional wound model in Sprague-Dawley rats over 21 days, assessing healing kinetics, histology, and pain behavior. The interaction between glycyrrhizic acid and the identified target PPIA, along with its immunomodulatory effects, was validated through molecular docking, molecular dynamics simulation, and RT-qPCR. Results: Our integrated analysis identified PPIA as the core target and glycyrrhizic acid as a key bioactive component of SJYHO. Animal experiments demonstrated that GA-Gel significantly accelerated wound closure, which was driven by its multi-faceted actions: reducing inflammation, promoting collagen deposition, alleviating pain, and modulating late-stage angiogenesis. Mechanistically, we confirmed that glycyrrhizic acid stably binds to PPIA. Furthermore, GA-Gel treatment mediated wound immune infiltration by specifically regulating CD8⁺ T cells, neutrophils, and memory B cells, an effect that was dependent on PPIA targeting. Conclusions: This study demonstrates that glycyrrhizic acid, formulated as GA-Gel, recapitulates the wound-healing benefits of SJYHO by specifically targeting PPIA and modulating the immune microenvironment. Our findings not only elucidate a key mechanistic pathway but also present GA-Gel as a rationally designed, clinically translatable therapy for acute and chronic wounds. Full article

Background: Luminal A breast cancer, the most common molecular subtype, is typically associated with a favorable prognosis. However, its systemic immune landscape remains largely uncharacterized. Methods: In this study, we used high-dimensional flow cytometry to characterize peripheral immune alterations in 13 patients with luminal A breast cancer compared to 14 age-matched healthy female controls. A total of 254 immune subsets were analyzed, including 23 innate populations and 231 T cell subpopulations, defined by detailed phenotypic and functional markers. Results: The main observations in the luminal A breast cancer group included a significant increase in neutrophils, plasmacytoid dendritic cells (pDCs), and CD4⁺ follicular T lymphocytes, as well as a reduced percentage of monocytes, conventional type 2 dendritic cells (cDC2), and CD4⁺CD196⁺ T cells. Conclusions: Despite being a preliminary study, these findings highlight distinct immune alterations in luminal A breast cancer and support the use of flow cytometry for identifying biomarkers, measurable biological indicators of disease presence, progression, or therapeutic response. Full article

Background: Systemic lupus erythematosus (SLE) is a multifactorial autoimmune disease in which cytotoxic T cells contribute to tissue damage through dysregulated effector pathways. CD107a (LAMP-1) serves as a functional marker of CD8⁺ T-cell degranulation and may reflect disease-related alterations in cytotoxicity. Objective: To investigate the expression of CD107a on cytotoxic T cells in SLE patients and evaluate its relationship with disease activity and immunological features. Methods: Demographic, hematological, and immunological profiles of SLE patients and controls were compared. Flow cytometry was used to evaluate CD3⁺, CD3⁺CD8⁺, CD4⁺, double-negative T cells, and CD107a⁺CD8⁺ subsets. Correlations with disease activity and diagnostic performance were assessed. Results: SLE patients showed anemia, thrombocytopenia, and lymphopenia compared with controls. Immunophenotyping revealed significantly elevated CD3⁺CD8⁺, CD107a⁺CD8⁺ T cells in SLE, and reduced CD4⁺ counts. While CD107a⁺CD8⁺ levels were strongly elevated, they did not correlate with disease activity scores, suggesting persistent upregulation of CD107a expression independent of clinical severity. ROC curve analysis indicated that CD3⁺ and CD3⁺CD8⁺ subsets had diagnostic utility, while double-negative T cells showed additional value. Conclusion: SLE is associated with increased CD107a⁺CD8⁺ T cells, reflecting heightened basal expression of this degranulation marker regardless of disease activity level. These findings underscore the role of altered cytotoxic T-cell function in SLE immunopathogenesis and support CD107a as a potential biomarker of immune dysregulation. Full article

Autism spectrum disorder (ASD) is a neurodevelopmental condition mainly characterized by social impairments and repetitive behaviors. An altered intestinal barrier morphology and increased transmucosal leaks have also been implicated in ASD; in fact, comorbidities such as gastrointestinal problems (leaky gut) have frequently been reported in these patients. The regulation of tight junctions (TJs) is essential in maintaining intestinal barrier morphology and in regulating the delicate balance of trafficking between the intestinal lumen and the submucosa. To date, there are no definitive treatments for ASD comorbidities; however, melatonin (MLT) represents a well-validated and tolerated treatment for sleep disorders in ASD patients. The potential beneficial effects of MLT on this disorder have been and continue to be better investigated. In this context, the present study examines the effects of oral MLT administration (10 mg/kg/day for 16 weeks) on the intestinal barrier in BTBR T + Itpr3tf/J (BTBR) mice, a validated ASD model. Morphological analyses of the ileum of these animals reveal modified villus height (Vh), crypt depth (Cd), and Vh–Cd ratios; an inflammatory state; and a decrease in Paneth cells. Moreover, these mice showed altered TJ expression compared to the control animals (C57BL6/J mice). Notably, MLT normalizes morphological indices and TJ expression, consistent with an improved gut barrier morphology. These data collectively suggest that orally administered MLT can promote the remodeling of the intestinal barrier; thus, we can suppose that MLT reduces gastrointestinal barrier leaks. The overall safety and economy of MLT use suggest that this indolamine could be efficacious as an adjuvant therapy to reduce the condition known as leaky gut. Full article

Toll-like receptor 9 (TLR9) and Toll-like receptor 3 (TLR3), which are widely expressed in dendritic cells (DCs), function as key pattern recognition receptors (PRRs) in the immune system. Their primary roles involve specifically detecting pathogen-associated molecular patterns (PAMPs): TLR9 recognizes unmethylated CpG motifs predominantly found in bacterial and viral DNA, while TLR3 identifies viral double-stranded RNA (dsRNA), a molecular signature associated with viral replication. Their specific agonists [CpG ODN (a TLR9 agonist) and poly(I:C) (a TLR3 agonist)] can effectively activate DCs and enhance the expression of immune activation-related molecules. In this study, by establishing a mouse primary dendritic cell model and a glioma-bearing mouse model, and employing techniques such as transcriptome sequencing, we found that combined stimulation with CpG ODN and poly(I:C) significantly enhanced the anti-tumor function of DCs: in vitro, DCs subjected to combined stimulation showed upregulation of anti-tumor-related surface markers, enhanced migratory capacity, and a more effective activation of CD8⁺ T cells; in vivo, a DC vaccine loaded with tumor lysate antigen and stimulated with this combined regimen significantly delayed the progression of glioma in tumor-bearing mice. Further investigation revealed that the underlying mechanism for this enhanced effect may involve TLR9 activation promoting TLR3 upregulation through the p38 MAPK-ATF3 signaling axis. Consequently, we designed a sequential stimulation protocol (first CpG ODN then poly(I:C)), which demonstrated a stronger anti-glioma effect compared to simple combined stimulation. This study provides a new strategy for enhancing the immune efficacy of DC vaccines and has potential significance for promoting the clinical translation of DC vaccines. Full article

The current knowledge on the histological structure of the gastrointestinal tract (GIT) in cetaceans is based on general descriptions. The aim of this study was to characterize the histology and expression of immune cell markers in samples from the GIT and lymph nodes (LNs) in a harbour porpoise (Phocoena phocoena) bycaught in the Cantabrian Sea. The thickness of the histological layers of the GIT was measured, being greater in the stomach and anal canal, although no significant differences were found among any intestinal segment (p = 0.448). Variation in thickness, morphology of the folds, and the presence of Peyer’s patches allowed the duodenal ampulla and the distal segments to be distinguished from the rest of the intestine. An immunohistochemical technique was performed to identify the following markers: IBA1 for macrophages, CD3 for T lymphocytes, and CD20 for B lymphocytes. The distribution of immune cells varied significantly along the GIT, with higher percentages of all three cell types in the distal intestine and the anal tonsil. Within the LNs, B lymphocytes represented the predominant cell population. This study provides the first description of the histological structure of the GIT and associated lymphoid tissue in a harbour porpoise, which will be useful for future research studies. Full article

Background/Objectives: Primary central nervous system lymphoma (PCNSL) has a markedly high proliferation rate, making early diagnosis and prompt therapeutic intervention essential. To accelerate diagnosis, our institution adopted flow cytometry (FCM) in conjunction with conventional histopathology, and this study therefore evaluated the diagnostic performance of FCM for PCNSL. Methods: We retrospectively analyzed 67 consecutive patients with suspected PCNSL who underwent intraoperative FCM between 2010 and 2023 based on preoperative imaging. B-cell clonality was defined as ≥20% CD19/CD20-positive cells with a κ/λ ratio of >3.0 or <0.5. Results: Using histopathology, we confirmed the presence of PCNSL in 42 patients, all diagnosed as having diffuse large B-cell lymphoma. Six cases (14.3%) were discordant (FCM-D). The sensitivity, specificity, and positive predictive value of FCM were 85.7%, 100%, and 100%, respectively. T-cell markers were significantly elevated in FCM-D cases (p < 0.01), although these were pathologically diagnosed as diffuse large B-cell lymphoma based on histology and immunohistochemistry. Conclusions: FCM yields reliable diagnostic information within hours of tissue collection and supports early therapeutic decisions in PCNSL. Discordant results may reflect reactive T-cell infiltration. This is the first study to present detailed subset analyses in PCNSL using FCM in correlation with pathology, underscoring its utility as a rapid diagnostic tool. Full article

The major histocompatibility complex (MHC) class I and class II molecules (abbreviated as MHC-I and MHC-II, respectively) are specialized in antigen presentation. Unlike the T cell receptors (TCRs), which have great variability, the MHC-I and MHC-II molecules essentially have no variability at all. It is apparent that the MHC-I and MHC-II molecules per se do not have the built-in ability to distinguish the huge populations of self-peptides from antigenic non-self-peptides. At present, the precise mechanism underlying the selective presentation of antigenic peptides by both MHC-I and MHC-II molecules is unclear. For an MHC-II molecule to gain the ability to selectively present antigenic (mostly foreign) peptides, it is hypothesized herein that all naïve CD4⁺ T cells in the body will release extracellular vesicles (EVs), which are specially designed for antigen-presenting cells (APCs); these EVs contain mRNAs that will be delivered to APCs and translated into an intracellular version of the TCR proteins (iTCR^II), which will help select antigenic peptides for presentation by the MHC-II molecules. Similarly, it is hypothesized that the fully activated CD4⁺ T cells will also release EVs, and these EVs contain different mRNAs for another intracellular version of the TCR proteins (iTCR^I), which will help pathogen-infected somatic cells to select the antigenic peptides (mostly from invading pathogens) for presentation by the MHC-I molecules. Understandably, while the iTCR^II proteins will work closely with the MHC-II molecules in the exogenous endocytic pathway, the iTCR^I proteins will work closely with the MHC-I molecules in the endogenous pathway. In this paper, a few other related hypotheses are also proposed, which jointly offer a plausible mechanistic explanation for the selective presentation of antigenic peptides by both MHC-I and MHC-II molecules. While the proposed hypotheses are partly supported by some experimental observations, it is hoped that these hypotheses will promote discussion and experimental testing of the mechanisms underlying the complex process of selective antigen presentation. Full article

Background/Objective: Dendritic cells (DCs) act as sentinels bridging innate and adaptive immunity, and their functions are strongly influenced by dietary and environmental factors. Phytochemicals such as α-Mangostin (A phytochemical, a xanthone derivative from Garcinia mangostina, known for its anti-inflammatory and antioxidant properties) are widely recognized for their antioxidant and anti-inflammatory effects, but their potential to modulate antiviral pattern recognition pathways remains unclear. This study investigated whether phytochemicals activate retinoic acid–inducible gene I (RIG-I: DDX58, a cytosolic receptor recognizing viral RNA and inducing antiviral responses)–dependent signaling in human monocyte-derived dendritic cells (MoDCs) and affect downstream T cell responses. Methods: MoDCs were generated from peripheral blood and stimulated with selected phytochemicals. RIG-I pathway–related transcripts were quantified by qPCR, and protein expression was assessed by Western blotting, intracellular flow cytometry, and immunofluorescence staining. Functional outcomes were evaluated by co-culturing MoDCs with T cells, followed by phenotypic analysis via flow cytometry and measurement of IFN-γ production by ELISA. Results: α-Mangostin stimulation increased RIG-I (DDX58) mRNA levels in MoDCs and induced time-dependent changes in intracellular protein expression. In co-culture, α-Mangostin–treated MoDCs tended to increase the proportion of OX40⁺ 4-1BB⁺ CD4⁺ T cells, accompanied by a significant elevation of IFN-γ levels in supernatants. Experiments with CpG-ODN (synthetic oligodeoxynucleotides mimicking bacterial DNA that activate TLR9) suggested context-dependent crosstalk between the TLR9 and RIG-I signaling axes. Conclusions: Phytochemicals, exemplified by α-Mangostin, prime antiviral responses in human DCs through upregulation of RIG-I and promote Th1-dependent immune responses. These findings suggest that phytochemicals may represent promising nutritional strategies to enhance antiviral immunity while mitigating excessive inflammation under infectious conditions. Full article

Foxp3+ regulatory T (Treg) cells play a pivotal role in inducing immune tolerance. The expression of Foxp3 in Treg cells depends on the stability of transcription factors that are directly linked to the molecular interplay between Stat5a and cyclin-dependent kinase CDK8/19. In this study, dendritic cells obtained from C57BL/6 male mice were co-cultured with CD4⁺ splenocytes obtained from Balb/c male mice to obtain alloantigen-specific CD4⁺ T cells. Next, these alloantigen-specific CD4⁺ T cells were cultured with the addition of the CDK8/19 inhibitor AS2863619 compound, TGF-β1, and IL-2 to induce their transdifferentiation into alloantigen-specific CD4⁺ Foxp3+ Treg cells. The efficacy of this cocktail in promoting the transdifferentiation of activated CD4⁺ lymphocytes into alloantigen-specific Treg cells (ag-Tregs) was further evaluated using Nanostring gene expression profiling, flow cytometry, ELISA, and in vivo migration assays. The results showed that the addition of the AS2863619 compound along with IL-2 generated effector memory ag-Tregs exhibiting tolerogenic activity, migration properties, and mechanisms for regulating immune homeostasis in the spleen. In conclusion, these findings suggest that the AS2863619-derived effector memory Tregs possess functional properties that support immune tolerance and regulate homeostasis in the spleen, thereby regulating the affinity of naïve T cells to alloantigens, highlighting their potential relevance in transplantology. Full article

Tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb), remains a major global health threat. Approximately one-quarter of the world’s population has an Mtb-specific immune response and are classified as having tuberculosis infection (TBI), with a lifelong 5–10% risk of developing TB disease. This risk is elevated in individuals with immune-mediated inflammatory diseases (IMID) undergoing immunosuppressive therapies. To evaluate the diagnostic accuracy of the 3-gene TB-SCORE for TB disease in individuals within the TB spectrum, including those with TBI-IMID in a low TB endemic country, we prospectively enrolled 104 individuals with TB, TBI, TBI-IMID, and healthy donors. The 3-gene TB-SCORE and Mtb-specific response were evaluated and correlated with the participant’s clinical status. Patients with TB disease showed a significantly lower TB-SCORE compared to other cohorts. ROC analysis showed moderate diagnostic accuracy for TB disease (AUC 0.70–0.71). TB-SCORE was unaffected by IMID status or timing of Mtb exposure. Mtb-specific CD4⁺ T cells had no correlation to TB-SCORE. This is the first evaluation of TB-SCORE as a diagnostic tool for TB disease in a low-endemic setting. While further validation is needed, our findings support its potential as a biomarker for TB disease, even in complex clinical settings involving IMID. Full article