Search Results (1,277)

BST2 has emerged as a multifunctional molecule that bridges antiviral defense, membrane architecture, and tumor immunity. Originally characterized as an interferon-inducible restriction factor that tethers virions to the plasma membrane, BST2 is now recognized as an oncogenic driver and immunoregulatory hub in diverse malignancies. In cancer, BST2 expression is frequently upregulated through promoter hypomethylation and transcriptional activation. Functionally, BST2 promotes proliferation, epithelial–mesenchymal transition, anoikis resistance, and chemoresistance, whereas its loss sensitizes tumor cells to proteotoxic and metabolic stresses. Beyond tumor cells, BST2 modulates the tumor microenvironment by promoting M2 macrophage infiltration, dendritic cell exhaustion, and natural killer (NK)-cell resistance, thereby contributing to immune evasion. Elevated BST2 expression correlates with poor prognosis in glioblastoma, breast, nasopharyngeal, and pancreatic cancers, and it serves as a circulating biomarker within small extracellular vesicles. In conclusion, BST2 is a dual-function molecule that integrates oncogenic signaling and immune regulation, making it an attractive diagnostic and therapeutic target for hematological and solid tumors. Full article

Baker’s yeast beta-glucan (BYBG) supplementation improves various aspects of immune system function, readiness, and response. The purpose of this study was to determine if the expression of immune maturation mRNA was also changed over the course of 6 weeks of BYBG supplementation at rest. In this exploratory study, a small group of participants (N = 20) were randomized into two groups: BYBG (weeks 0–2 = 50 mg/d; 2–4 = 125 mg/d; and 4–6 = 250 mg/d) or placebo. Blood samples were collected at 0, 2, 4, and 6 weeks and analyzed for the expression of 785 mRNA (NanoString nCounter platform and Nanotube software; R v3.3.2). A total of 42 mRNAs in 21 annotated pathways (antigen presentation, apoptosis, B cell memory, cell cycle, chemokine signaling, cytotoxicity, DAP12 signaling, hypoxia response, IL-1 signaling, IL-10 signaling, MAPK signaling, myeloid immune response, NF-kB signaling, NK activity, Notch Signaling, PD1 signaling, Senescence/Quiescence, T cell checkpoint signaling, TCR signaling, TLR signaling, and TNF signaling), were significantly affected by BYBG at various time points. It is reasonable to speculate that the observed mRNA and associated pathways may underlie previously reported improvements in immune function with BYBG. Full article

Patients with inflammatory bowel disease (IBD) frequently fail to achieve protective immunity after hepatitis B vaccination, even with intensified vaccination schedules. In this observational real-world study, 18 patients with IBD who were seronegative for hepatitis B virus (HBV) received three standard doses of the Engerix-B^® vaccine (at 0, 1, and 6 months). After immunisation, patients were classified into responders and non-responders according to their serological response. Blood samples were collected before the first dose and after completion of the vaccination schedule. Responders activated pathways that supported durable protection, including conventional dendritic cells type 1 mobilisation, expansion of IgG plasmablasts, and preservation of B- and T-cell memory. In contrast, non-responders displayed a more inflammatory innate profile, characterised by enrichment of CCR2⁺ monocytes. They also showed higher baseline Treg frequencies, which may suppress effective effector responses, together with impaired natural killer (NK) activation and progressive loss of memory potential. This study shows that hepatitis B vaccine failure in inflammatory bowel disease reflects a convergence of excessive immune regulation, inflammatory activation, and loss of memory potential, underscoring that no single pathway can explain the impaired response. Full article

MICB-targeting CAR-NK (chimeric antigen receptor-modified natural killer cells) therapy may serve as off-the-shelf immunotherapy. We designed soluble Anti-MICB-scFv blocks tumor immune evasion targeting the MICB antigen, thereby enhancing CAR-NK cytotoxicity while reactivating endogenous immune attacks against malignancies. The Anti-MICB-CAR includes two Anti-MICB-scFv connected by an F2A linker, the CD8 hinge and transmembrane domain, the 4-1BB co-stimulatory domain, the CD3ζ activation domain, and IL-15. The expression efficiency of Anti-MICB-CAR in NK cells was investigated by flow cytometry; ELISA demonstrated that Anti-MICB-CAR-NK secreted free Anti-MICB-scFv and detected IL-15 secretion. Flow cytometry and CCK8 were utilized to study Anti-MICB-CAR-NK on tumor cell viability. The PANC-1 xenograft model was established in order to elucidate the anti-tumor effects of Anti-MICB-CAR-NK in vivo. In vitro investigations have demonstrated that the treatment of tumor cells with Anti-MICB-CAR-NK supernatant + NK cells or Anti-MICB-CAR-NK cells not only significantly increased the cytotoxic activity of tumor cells, but also secreted and produced higher levels of IL-15, IFN-γ, TNF-α, perforin, and granzyme B compared with NK cells. Anti-MICB-CAR-NK cells exhibit strong cytotoxic activity against tumor cells with high MICB expression. In vivo, Anti-MICB-CAR-NK cells exhibited a substantial inhibitory effect on tumor growth. The IHC results reveal that Anti-MICB-CAR-NK cells show a more pronounced ability to infiltrate the tumor. We demonstrated the successful expression of Anti-MICB-CAR in NK cells, which enhances the anti-tumor activity of NK cells both in vitro and in vivo. This stress ligand-targeting approach provides a promising strategy for solid tumors. Full article

The immune system comprises a complex network of cells that continuously change during activation, infection, and the maintenance of balance. Immunophenotyping offers valuable insights into the regulation of immune responses. We systematically characterized the expression profile of CD99 ligands across distinct immune cell subsets using both conventional and high-dimensional flow cytometry. CD99 ligands were detected on NK cells and monocytes under both resting and IL-2-activated conditions, with non-classical monocytes and CD56 Dim NK cells exhibiting the highest expression levels. Notably, ligand expression in these subsets was further enhanced following IL-2 activation. In contrast, T lymphocytes (CD3⁺) displayed low basal levels of CD99 ligand expression, which increased modestly upon activation. Cellular activation was accompanied by an expansion of specific immune phenotypes characterized by elevated CD99 ligand expression alongside the upregulation of activation markers such as CD69 and CD137. Collectively, these findings suggest that the expression of the CD99 ligands may serve as an indicator of immune activation and demonstrate subset-specific regulation, particularly in response to IL-2 stimulation. These findings have revealed the distinct expression patterns of CD99 ligands, emphasizing their crucial role in modulating immune responses. Full article

The intratumoral microbiota, comprising bacteria, fungi, and viruses within the tumor microenvironment, actively influences carcinogenesis. Key mechanisms include the induction of host DNA damage, modulation of critical oncogenic signaling pathways such as WNT-β-catenin, NF-κB, and PI3K, and the orchestration of inflammatory processes. The microbiome’s interaction with the host immune system is complex and bidirectional. On one hand, specific microbes can foster a pro-tumorigenic niche by suppressing the activity of cytotoxic T cells and natural killer (NK) cells or by promoting the accumulation of immunosuppressive cell types like tumor-associated macrophages (TAMs). On the other hand, microbial components can serve as neoantigens for T cell recognition or produce metabolites that reprogram the immune landscape to enhance anti-tumor responses. The composition of this microbiome is emerging as a crucial factor influencing the outcomes of immunotherapies. Prospective investigations in cancer immunotherapy ought to prioritize mechanistic inquiry employing integrative multi-omics methodologies. The execution of meticulously designed clinical trials for the validation of microbial biomarkers, and the systematic, evidence-based development of microbiome-targeted therapeutic interventions aimed at enhancing antitumor immune responses. Full article

Major histocompatibility complex class I-like related gene A (MICA) is the most polymorphic non-classical HLA gene. MICA proteins are expressed at low levels on the surface of normal cells but are highly expressed on the surface of tumor cells. Its most important biological function is to bind to activating receptors on the surface of natural killer (NK) cells or CD8+ T cells, then activate these immune cells to exert immune killing effects. Multiple studies have shown that the amino acids at specific loci in the MICA molecule can significantly affect its binding ability to NKG2D. The binding strength of MICA-NKG2D significantly affects the anti-tumor effect of NK cells in the body and the prognosis of many tumor patients. However, the strong MICA-NKG2D interaction can trigger negative feedback against this immune response by down-regulating the expression of NKG2D or generating soluble MICA, weakening the overly intense immune response. Therefore, simply evaluating the intensity of the anti-tumor immune response from the perspective of the amino acid polymorphism of MICA affecting its binding ability to NKG2D also has limitations. We review the effects of MICA amino acid polymorphism on the affinity of the NKG2D signal pathway and analyze in detail the specific role of MICA amino acid polymorphism in tumor immunity. The study provides a reference for understanding the mechanism of anti-tumor immune response by NK cells or other immune cells, as well as a theoretical basis for considering the MICA-NKG2D signal axis for anti-tumor immune therapy in future clinical practice. Full article

Diabetic kidney disease (DKD) is a leading cause of end-stage renal disease worldwide. However, the inflammatory mediators that causally drive disease progression remain incompletely defined. In this study, we used a multi-omics approach that combined single-cell RNA sequencing, spatial transcriptomics, pseudotime trajectory analysis, cell-to-cell communication analysis, and Mendelian randomization (MR) to investigate the role of tumor necrosis factor receptor superfamily member 1A (TNFRSF1A) in DKD development. Findings were further validated in zebrafish embryos depleted of pdx1, an established model of DKD. Spatial transcriptomic analysis showed that TNFRSF1A is enriched in cortical kidney regions. Pseudotime analysis revealed progressive immune reprogramming, with an early predominance of T and NK cells and gradual shift to myeloid infiltration and B-cell expansion. Cell-to-cell communication analysis highlighted IL-1β and related signaling pathways that increase NF-κB activity. Mendelian Randomization analysis, complemented by PPI network mapping, identified TNFRSF1A (OR = 1.78, 95% CI: 1.17–2.71, p = 0.007) as a gene with genetic evidence supporting a causal association. Consistent with the human data, experiments in zebrafish showed that TNFRSF1A expression increases significantly following pdx1 knockdown (p = 0.0025). Together, these findings support a role for TNFRSF1A in immune microenvironment reprogramming in DKD, while not excluding the involvement of additional regulatory pathways. Full article

Moringa oleifera, widely recognized as the horseradish tree or drumstick tree, is classified within the Moringaceae family, which comprises 13 species predominantly distributed across tropical and subtropical regions. The plant possesses a variety of therapeutic, nutritional, and beneficial health properties, including its potential to enhance the immune system. The present work provides extensive bibliographic research addressing the chemical composition of Moringa oleifera and its immunomodulatory properties with a focus on the cellular and molecular mechanisms involved in the regulation of immune function, which is crucial in unchecked cell proliferation and metastasis. The chemical composition of Moringa oleifera, including kaempferol, chlorogenic acid, quercetin, and niazimicin, varies between different biological parts of the plant (seeds, leaves, roots, and stems). The presence of these various chemical compounds contributes to the plant’s effect on the immune response via different pathways. Several studies indicate that Moringa oleifera mitigates inflammation by suppressing key pro-inflammatory mediators, such as TNF-α, IL-1β, inducible nitric oxide synthase (iNOS), prostaglandin E2 (PGE-2), and cyclooxygenase-2 (COX-2), while simultaneously enhancing anti-inflammatory mediators through activation of PPAR-γ. Furthermore, the immunomodulatory properties and possible application in health promotion and disease prevention, especially in cancer therapy, are discussed. Studies indicate that Moringa oleifera can modulate the tumor microenvironment (TME) by reducing Treg polarization, enhancing NK cell cytotoxicity, and prompting the proliferation and clonal expansion of CD8⁺ and CD4⁺ T lymphocytes. Together, Moringa oleifera could be considered for the treatment of conditions related to immune dysregulation, such as cancer. Full article

Chimeric antigen receptor (CAR)-based immunotherapy has shown considerable promise in cancer treatment by redirecting immune effector cells to recognize and eliminate tumor cells in an antigen-specific manner. While CAR-T cells bearing tumor-specific CARs have shown remarkable success in treating some hematological malignancies, their clinical application is limited by cytokine release syndrome, neurotoxicity, and graft-versus-host disease. In contrast, CAR–natural killer (NK) cells retain their multiple forms of natural anti-tumor capabilities without the pathological side effects and are compatible with allogeneic “off-the-shelf” application by not requiring prior activation signaling. Despite CAR-NK therapies showing promising results in hematological malignancies, they remain limited as effector cells against solid tumors. This is primarily due to the complex, immunosuppressive tumor microenvironment (TME), characterized by hypoxia, nutrient depletion, lactate-induced acidosis, and inhibitory soluble factors. Collectively, these significantly impair NK cell functionality. This review examines challenges faced by CAR-NK therapy in combating solid tumors and outlines strategies to reduce them. Barriers include tumor antigen heterogeneity, immune escape, trogocytosis-mediated fratricide, rigid structural and metabolic barriers in the TME, immunosuppressive factors, and defective homing and cell persistence of CAR-NK cells. We also emphasize the impact of combining other complementary immunotherapies (e.g., multi-specific immune engagers and immunomodulatory agents) that further strengthen CAR-NK efficacy. Finally, we highlight critical research gaps in CAR-NK therapy and propose that cutting-edge technologies are required for successful clinical translation in solid tumor treatment. Full article

Photosynthetic prokaryotes known as cyanobacteria produce an extensive range of primary and secondary metabolites that serve multiple biotechnological and biomedical purposes. The non-model filamentous Phormidium species capture researchers’ attention through their biotechnological potentials from diverse metabolites and their ability to thrive in tough environments while producing bioactive compounds. In this study, a thermotolerant strain of Phormidium ambiguum was isolated from the Chundzha thermal springs in southeastern Kazakhstan and characterized morphologically, physiologically, and biochemically. This cyanobacterium demonstrated fast growth in its culture media along with significant accumulation of proteins (44.8% DM), carbohydrates (45% DM), and photosynthetic pigments like chlorophyll a and valuable carotenoids, including b-carotene, myxoxantophyll and zeaxanthin. The LC-ESI-MS/MS analysis of cyanobacterial non-polar extract identified 150 potential metabolites which include fatty acid derivatives, terpenoids and carotenoid-related compounds known for their antioxidant and antimicrobial properties, as well as immune system stimulation. Biological assays confirmed a weak antioxidant capacity in the DPPH test, while in immunological assays, the extract of P. ambiguum stimulated T lymphocyte proliferation and activation, as well as NK cell proliferation in vitro. It also exhibited moderate antibacterial activity towards tested Gram-negative and Gram-positive bacterial strains. While additional studies are required to address environmental robustness, biosynthetic regulation, and practical scalability, the present findings indicate that P. ambiguum represents a valuable non-model cyanobacterium for exploratory bioprospecting. Its metabolite profile and observed bioactivities support further investigation of this thermotolerant strain as a potential source of immunomodulatory, antioxidant, and antimicrobial compounds under controlled conditions. Full article

Unexplained infertility and idiopathic recurrent pregnancy loss (RPL) have a prevalence of 1–5% of women of reproductive age in different populations. There are a few reports comparing the circulating immune cell populations and subpopulations in these medical entities in admixed populations. The study aimed to assess the different leukocyte, mononuclear cell populations, and T lymphocyte subpopulations and HLADR expression, as a marker of activation, in an admixed group of Venezuelan women: 80 controls, 73 women with RPL (53 primary, 20 secondary), and 26 infertile (20 primary, six secondary). Endometriosis was clinically ruled out in all patients and controls. Total leukocytes were 10–12% higher (p < 0.0001) in the infertile group, while neutrophils were 11% in the infertility group (p < 0.0001). In contrast, lymphocytes, CD3CD4 cells, NK cells, and HLADR+ cells were elevated (10–15, 18–22, 50–60, and 700–800% increase, respectively) in all patient groups. Changes in B cell numbers and monocyte counts were also observed. HLADR expression was significantly increased (p < 0.0001) in T cells, CD56+ cells, and monocytes of all patients. In infertile patients, a correlation was recorded between HLADR and T memory cells. Marked differences in peripheral blood leukocytes, NK cells, monocytes, T-cell populations, and HLADR suggest a proinflammatory effect. HLADR can be used as a simple biomarker to monitor pharmacological treatment in these patients. Full article

This study evaluated hepatic pathological and phenotypic alterations, along with the inflammatory response, following sequential dengue virus (DENV) infection in Callithrix penicillata, a relevant model for human endemic scenarios. Twenty-six animals were initially infected subcutaneously with DENV-3. Thirteen were euthanized between 1 and 7 days post-infection (dpi) to assess the acute phase, and up to 60 dpi for the convalescent phase. The remaining animals received a secondary DENV-2 infection two months later. Liver samples underwent histopathological and immunohistochemical analysis. Viral antigens were identified in hepatocytes, Kupffer cells, and Councilman bodies. Observed liver changes included apoptosis, lytic necrosis, midzonal inflammation, Kupffer cell hyperplasia and hypertrophy, sinusoidal dilation, and hemosiderin deposition. Both primary and secondary infections increased activated macrophages, NK cells, S-100 protein, and B lymphocytes. Primary infection was associated with elevated CD4⁺ T cells, IFN-γ, TGF-β, IL-10, and Fas expression, whereas secondary infection induced higher IFN-γ, TNF-α, IL-8, Fas, and VCAM levels. These findings mirror hepatic alterations in severe human dengue cases and underscore the role of direct viral effects and immune dysregulation in liver injury. The results support C. penicillata as a suitable non-human primate model for studying DENV pathogenesis. Full article

Human leukocyte antigen (HLA)-E, a non-classical class I molecule with limited polymorphism, bridges innate and adaptive immunity. Traditionally, the role of HLA-E had been associated with regulating natural killer (NK) cell activity via CD94/NKG2 receptors, by presenting self-peptides derived from the leader sequence of HLA-I. Recent findings reveal its ability to present pathogen-derived peptides to CD8⁺ T cells, eliciting unconventional cytotoxic responses. This review examines the expanding role of HLA-E-restricted T cells in viral and bacterial infections and their capacity to recognize diverse microbial peptides and enhance immune response when classical HLA pathways are impaired. We also highlight key advances in immunotherapy and vaccine development, including CMV-vectored platforms, donor-unrestricted TCR-based strategies, and peptide prediction algorithms. The minimal polymorphism of HLA-E, its resistance to viral immune evasion, and its ability to present conserved pathogen peptides position it as a promising target for universal vaccines and next-generation immunotherapies. Understanding these unconventional roles may pave the way for broadly applicable immunotherapies and vaccines against infectious diseases. Full article

Background: The link between clinical recovery and immune restoration after severe COVID-19 remains poorly defined. Although most survivors experience symptomatic improvement, persistent symptoms have been hypothesized to reflect ongoing immune dysregulation. Methods: This prospective cohort study followed 93 unvaccinated adults with RT-PCR-confirmed moderate-to-critical COVID-19 at 3, 6, and 12 months post-discharge. Clinical assessments used structured interviews to evaluate the persistent symptoms. Peripheral blood analyses were used to measure lymphocyte subsets, immunoglobulins, and complement components. Results: Clinical recovery was substantial; fatigue prevalence declined from 70.9% to 24.7% and dyspnea prevalence from 81.7% to 25.8% by 12 months (p < 0.001 for both). However, immune recovery exhibited divergent patterns. Activated T cells (CD3⁺HLA-DR⁺) decreased significantly (from 20% to 13%; p < 0.001), complement C3c levels paradoxically increased from 1.23 to 1.35 g/L (p < 0.001), and serum IgA increased by 32% (p = 0.003). NK cells remained stable overall but were persistently reduced in a subset (~25%) of patients, particularly among those with fatigue and dyspnea. Critical illness was associated with slower T-cell resolution, prolonged IgM elevation, and increased complement activity. Conclusions: One year after hospitalization, most patients achieved substantial clinical improvement, but immune reconstitution lagged behind. These findings highlight the dissociation between clinical and immunological recovery and suggest that persistent immune dysregulation may be associated with long COVID manifestations. Incorporating immune monitoring into post-COVID care may help identify patients at risk of prolonged sequelae and guide targeted therapeutic strategies. Full article