Search Results (1,430)

Cancer immunoprevention leverages the immune system’s surveillance mechanisms to mitigate tumor development. Vaccines that constitute a tumor antigen and an immune adjuvant are perceived as immunoprevention modalities. However, relevant tumor antigens are unknown for non-viral cancers, which constitute most human cancers. Our group has recently shown that SA–4–1BBL, a novel agonist of CD137 receptor, but not antibodies, shows immunoprevention efficacy against various tumors. Advanced bioinformatics analyses of bulk RNA-seq data were conducted to elucidate mechanisms underlying cancer immunoprevention. Mice received subcutaneous injections of SA–4–1BBL or agonistic 3H3 antibody, and the injection-site tissue (IS) and draining lymph nodes (LN) were analyzed for differential gene expression. SA–4–1BBL induced a compartmentalized and temporally dynamic immune program characterized by early effector activation at IS and sustained immune regulation in draining LN. K-means clustering of 4564 DEGs identified eight functionally distinct clusters. IS-enriched clusters contained activation genes for CD4⁺ T and NK cells, including Cd28, Klra1, Cd4, Cd40, and Cd40l, while LN clusters were enriched for regulatory genes (Tnfaip3, Irf5, Col1a2) that ensure immune priming and homeostatic restraint for a balanced response. SA–4–1BBL generated a more selective and durable activation of adaptive immunity, TCR signaling, Th1/Th2 differentiation, and NK cytotoxicity. 3H3 activated broader innate inflammatory programs, including Toll-like receptor and neurodegeneration-linked pathways. IMPRes analysis showed that SA–4–1BBL activates sequential immune-regulatory circuits centered on Stat1, Cd247, and Ifng and modulates the CD151–TGF-β axis. These findings demonstrate that SA–4–1BBL elicits a balanced immune response, ensuring both safety and efficacy in preventing cancer development. Full article

We present the single-cell transcriptomic analysis of peripheral blood mononuclear cells (PBMC) from individuals during acute HIV-1 infection caused by viral strains circulating in Russia and the Former Soviet Union (FSU) countries. Using 10x Genomics single-cell RNA sequencing (scRNA-seq) on the Illumina NextSeq 550 platform, we have analyzed scRNA-seq data from three treatment-naive patients (viral load > 1 × 10⁶ copies/mL, estimated infection duration ≤ 4 weeks) and three healthy donors. Data integration (Seurat, Harmony), automated cell-type annotation (CellTypist), and GeneOntology (GO) enrichment analysis for highly expressed and low-expressed genes revealed a profound reorganization of transcriptional programs across key immune populations, including memory CD4⁺ and CD8⁺ T cells, non-classical monocytes and natural killer cells (NK-cells). We observed signatures of hyperactivation of pro-inflammatory pathways (NF-kB, TNF, and type I/II interferon signaling), upregulation of genes associated with cellular migration (CXCR4, CCR7) and metabolic adaptation (oxidative phosphorylation components), alongside a mixed pro- and anti-apoptotic expression profile. Notably, our data pointed to a pronounced dysregulation of the TGF-β and mTOR signaling cascades, disrupted intercellular communication networks—particularly between cytotoxic cells and their regulators—altered expression of genes implicated in disease progression (OLR1, SERPINB2, COPS9) and viral persistence control (NEAT1, NAF1). This work provides an initial single-cell transcriptional atlas characterizing early immune responses to HIV-1 sub-subtypes A6 and CRF63_02A6, the predominant drivers of the HIV epidemic across the FSU region. Full article

Ovarian cancer (OC) is a particularly lethal gynecological malignancy with few treatment options due to its late-stage diagnosis, extensive genetic heterogeneity, and frequent development of resistance to existing therapies. Immunotherapy has revolutionized the management and clinical outcome of numerous solid tumors, but its clinical benefit for OC has been limited, in part due to an extremely immunosuppressive tumor microenvironment (TME) and diverse, overlapping immune evasion mechanisms. In this review, we present a comprehensive and timely synthesis of next-generation immunotherapeutic approaches for ovarian cancer, emphasizing strategies that overcome the immunosuppressive tumor microenvironment and improve clinical responsiveness. We describe the emerging molecular mechanisms of immune evasion in OC, including altered antigen presentation, inhibition of T-cell activation (e.g., via immunological checkpoints, metabolic reprogramming), polarization of tumor-associated macrophages (TAMs), and dysfunction of natural killer (NK) cells. We also critically examine several emerging therapeutic approaches, including combination immune checkpoint blockade (ICB), bispecific T-cell engagers (BiTEs), neoantigen-based vaccines, chimeric antigen receptor (CAR)-T- and CAR-NK-cell therapies, oncolytic viruses (OVs), and nanoparticle-mediated immunomodulation. In addition, we highlight recent advances in tumor microenvironment–targeted therapies for ovarian cancer, focusing on strategies that modulate non-lymphoid components such as cancer-associated fibroblasts (CAFs), hypoxia-driven signaling, and the PI3K/AKT/mTOR axis to enhance antitumor immune responsiveness. Finally, we discuss how predictive biomarkers, multi-omics systems, and patient-derived organoid models are accelerating the development and deployment of precision immunotherapies for OC. We would like to highlight the translational promise of next-generation immunotherapies and identify novel molecular targets that may be leveraged to achieve durable responses in OC. Full article

SLAMF7, also known as CD319, a SLAM (signaling lymphocytic activation molecule) family receptor, is relatively weakly expressed on chronic lymphocytic leukemia (CLL) B cells. This study evaluated the ability of elotuzumab (E), an anti-SLAMF7/CD319 antibody, to induce antibody-dependent cellular cytotoxicity (ADCC) against CLL cell lines (MEC-1, MEC-2, CI, HG-3, PGA-1, WA-OSEL). ADCC was assessed by flow cytometry using E (100 μg/mL), rituximab (R, 100 μg/mL), and their combination (E + R). CLL lines served as targets (T), while peripheral blood mononuclear cells (PBMCs) or NK cells from healthy donors served as effectors (E) at an 8:1 E:T ratio for 4 h. With PBMCs, E-induced ADCC ranged from 1.3 ± 1.2% (PGA-1) to 14.6 ± 8.1% (MEC-1); R-induced ADCC ranged from 9.2 ± 4.6% (PGA-1) to 16.6 ± 9.4% (WA-OSEL). With NK cells, E-induced ADCC ranged from 1.8 ± 3.7% (PGA-1) to 27.3 ± 4.7% (MEC-1); R-induced ADCC ranged from 5.1 ± 4.3% (PGA-1) to 27.5 ± 13.6% (CI). E outperformed R in MEC-1, while R was superior elsewhere. Cell lines with higher SLAMF7/CD319 expression displayed increased sensitivity to E. Cell lines with del17p showed higher SLAMF7/CD319 expression. The combination of E + R showed no significant synergy over monotherapies. In conclusion, elotuzumab induced significant ADCC in CLL cells, warranting further therapeutic evaluation. Full article

Immune checkpoint proteins including PD-1, CTLA-4, LAG-3, TIM-3, and TIGIT regulate T-cell functions, which are essential for anti-tumor immunity. Over-expression of these immune checkpoint proteins leads to T-cell exhaustion and a significant impairment of anti-tumor immunity. Rejuvenation of effector T-cell function with immune checkpoint inhibitors (ICI) restores anti-tumor immunity, which translates into clinical efficacy in the frontline and salvage treatment of various hematological malignancies. Efficacy of ICIs is highest in classical Hodgkin lymphoma, primary mediastinal large B-cell lymphoma, and NK/T-cell lymphomas, and modest in immune-privileged-site lymphomas and cutaneous T-cell lymphoma. However, in myeloid malignancies and multiple myeloma, the efficacy of ICIs remains doubtful. In addition to being used as single agents, ICIs have also been combined with other ICIs; as well as chemotherapy, antibody drug conjugates, and epigenetic agents (histone deacetylase inhibitors and hypomethylating agents). More innovative strategies include the use of ICIs in the context of allogeneic haematopoietic stem cell transplantation and chimeric antigen receptor T-cell therapy. This review synthesizes current evidence for the use of ICI in different haematological malignancies, and highlights future directions toward biomarker-driven, rationally designed therapeutic combinations. Full article

Recurrent pregnancy loss (RPL) is defined as the loss of two or more pregnancies before the 22nd gestational week and affects 10–15% of clinical pregnancies. Despite extensive diagnostics, over 50% of RPL cases remain unexplained, suggesting an important role for immunological mechanisms. Sex hormones (SH) are key regulators of immune responses during pregnancy; however, their influence on immune checkpoint proteins (ICPs) is poorly understood. This study evaluated the effects of progesterone, β-estradiol, and dihydrotestosterone (DHT) on ICP expression on immune cells, including Treg, NK, NKT, TC, Th, and T cells, collected from pregnant women and patients with unexplained RPL (uRPL). Peripheral blood mononuclear cells from 20 pregnant women and 20 uRPL patients were cultured for 48 h with SH. The expression of the first generation of ICPs—PD-1 and TIM-3—and the second—LAG-3, TIGIT, and VISTA—on T, NK, and NKT cells was analyzed by the flow cytometry method. In pregnant women, SH exerted modest effects, with DHT increasing VISTA and LAG-3 expression, while progesterone and estradiol mainly upregulated LAG-3 and TIM-3 on cytotoxic cells. In contrast, uRPL immune cells showed pronounced SH sensitivity, characterized by increased TIM-3 and VISTA expression and reduced TIGIT expression, particularly after DHT stimulation. In conclusion, SH modulates ICP expression in a cell-specific manner, with stronger effects observed in uRPL patients’ lymphocytes. These findings highlight a potential role for hormonal and ICP-targeted strategies in RPL management. Full article

The World Health Organization (WHO) and International Consensus Classification (ICC) systems have classified EBV-positive NK/T-cell neoplasms in adults and EBV-positive T/NK-cell lymphoid lymphoproliferative disorders (LPD) in children. Recent molecular profiling techniques have revealed the pathogenesis of these disorders, showing interactions among EBV-encoded proteins, host immune responses, and genetic alterations. Extranodal NK/T-cell lymphoma (ENKTL) shows molecular diversity, with various subtypes (TSIM, MB, and HEA) identified through a multiomics approach. Aggressive NK-cell leukemia (ANKL) has mutations in JAK/STAT, epigenetic regulators, and TP53 pathways. EBV-positive nodal T- and NK-cell lymphoma (ENTNKL) is a new entity, distinguished by primary nodal presentation and a unique molecular profile. Severe mosquito bite allergy (SMBA), hydroa vacciniforme lymphoproliferative disorder (HVLPD), and systemic chronic active EBV disease (CAEBV) are rare childhood EBV-driven LPDs defined by clinico-pathologic criteria, with largely unexplored genomic landscapes. Studies of CAEBV samples have found ENKTL-like driver mutations, including DDX3X and KMT2D, in EBV-infected NK/T cells, while KMT2D and chromatin modifier mutations were common in HVLPD. Comprehensive molecular sequencing of SMBA and Systemic EBV-positive T-cell lymphoma of childhood remains lacking. These findings suggest all EBV⁺ NK/T-cell LPDs exist on a biological continuum of viral oncogenesis. The integration of clinical, pathological, and molecular information aims to create a more accurate classification system, enabling better risk evaluation and tailored treatment strategies for patients with these complex disorders. Full article

Mutations in TP53 inhibit p53 protective behaviors including cell cycle arrest, DNA damage repair protein recruitment, and apoptosis. The ubiquity of p53 in genome-stabilizing functions leads to an aberrant tumor microenvironment in TP53-mutated myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). Profound immunosuppression mediated by myeloid-derived suppressor cells, the upregulation of cytokines and cell-surface receptors on leukemic cells, the suppression of native immune regulator cells, and metabolic aberrations in the bone marrow are features of the TP53-mutated AML/MDS marrow microenvironment. These localized changes in the bone marrow microenvironment (BMME) explain why traditional therapies for MDS/AML, including chemotherapeutics and hypomethylating agents, are not as effective in TP53-mutated myeloid neoplasms and demonstrate the dire need for new treatments in this patient population. The unique pathophysiology of TP53-mutated disease also provides new therapeutic approaches which are being studied, including intracellular targets (MDM2, p53), cell-surface protein biologics (immune checkpoint inhibitors, BiTE therapy, and antibody–drug conjugates), cell therapies (CAR-T, NK-cell), signal transduction pathways (Hedgehog, Wnt, NF-κB, CCRL2, and HIF-1α), and co-opted biologic pathways (cholesterol synthesis and glycolysis). In this review, we will discuss the pathophysiologic anomalies of the tumor microenvironment in TP53-mutant MDS/AML, the hypothesized mechanisms of chemoresistance it imparts, and how novel therapies are leveraging diverse therapeutic targets to address this critical area of need. Full article

Background: Axillary lymph node (ALN) metastasis is a critical prognostic determinant in breast cancer (BC) that informs surgical management. However, surgically clearing the axilla carries morbidity, so less invasive methods of risk-stratifying patients are needed. ALN fine needle aspiration (FNA) is currently used to detect BC metastases, but these samples also contain immune cells. Methods: Cells obtained via FNA from BC-patient-derived ALNs were analysed using flow cytometry. Results: FNA acquires sufficient leukocytes for comprehensive immunophenotyping of reactive, patient-derived ALNs. All CD4⁺ and CD8⁺ T-cell subsets (naïve, terminal effector, central memory, and effector memory) and rarer (<2%) natural killer (NK) and plasmacytoid dendritic cell (pDC) populations are represented. Importantly, the immune-cell profile of one reactive ALN appears to reflect the immune status of the patient’s axilla. Furthermore, FNA captures immune differences between patients with ≤1 or ≥2 metastatic ALNs. Increased numbers of naïve CD4⁺ T cells, but fewer terminal effector, central memory, and effector memory subpopulations, were obtained from patients with ≥2 metastatic ALNs. Moreover, despite their sparse distribution pattern on whole-section immunohistochemistry (WSI), FNA revealed that CD56⁺ NK cell activation receptors were decreased in patients with ≥2 metastatic ALNs. Finally, FNA captured a decrease in pDCs in patients with ≤1 metastatic ALNs, despite their clustered distribution pattern on WSI. Conclusions: FNA is not only feasible for sampling leukocytes from reactive, patient-derived ALNs, but also identifies immune-cell profiles that reflect axillary tumour burden in BC. Thus, this technique could be used to risk-stratify BC patients in the future. Full article

Lidocaine, an amide-type regional anesthetic, has been an important medication in the field of anesthesia since its clinical approval. Recently, lidocaine has emerged as a powerful immunomodulatory agent beyond its classical anesthetic properties. This review has summarized the recent basic and clinical studies with sufficient evidence on the multifaceted effects of lidocaine on both innate and adaptive immune cells, including macrophages, neutrophils, eosinophils, basophils, natural killer (NK) cells, mast cells, dendritic cells (DCs), monocytes, and T lymphocytes. We have also detailed how lidocaine affects critical cellular processes, such as cellular polarization, cytokine production, phagocytosis, and apoptosis, through multiple signaling pathways, including NF-κB, TLR4/p38 MAPK, voltage-sensitive sodium channels, HIF1α, TGF-β/Smad3, AMPK-SOCS3, TBK1-IRF7, and G protein-coupled receptors. These immunoregulatory effects of lidocaine are dependent on its concentration, duration of action, and the microenvironment. The immunomodulatory actions of lidocaine may contribute to its potential therapeutic value in various settings of diseases, such as cancer, sepsis, acute lung injury, asthma, organ transplantation, ischemia–reperfusion injury (IRI), and diabetes. We propose that lidocaine can be repurposed as an immunomodulator for treating immune-mediated inflammatory diseases. However, future research should define optimal dosing strategies, validate its mechanisms of action in clinical trials, and explore its novel clinical applications as a complementary immunotherapy. Full article

Background and Objectives: Toll-like receptors (TLRs) are pattern recognition receptors with an essential role in regulating both the innate and adaptive immune response. Given their pleiotropic effects in mounting an immune response, previous studies have proposed targeting these TLRs might render alternative strategies for cancer therapy. Synthetic immune response modifiers, such as imidazoquinolines, stimulate the immune cells by activating Toll-like receptors, particularly TLR7/8 receptors, consequently mounting an immune response. Agonists of this class activate, via TLR-mediated signaling, dendritic and B cells, as well as myeloid cells and T cells, thus exhibiting good prospects for cancer immunotherapy. In the present study, we sought to evaluate the effect of imiquimod and gardiquimod, two TLR 7 and 7/8 agonists, respectively, on tumor growth and phenotype of NK cells associated with melanoma. Materials and Methods: We generated a syngeneic model of melanoma in C57BL/6J mice by subcutaneously injecting murine melanoma cells and monitoring tumor growth. Starting on day 8 or 14, we applied TLR agonists either intratumorally or topically and followed the tumor dynamics and NK cell-associated pattern. Results: Our results suggest that both TLR agonists displayed an antitumor effect along with a phenotypically activated profile of NK cells. Both imiquimod and gardiquimod treatment inhibited tumor growth, with gardiquimod showing an increased potency compared to imiquimod. Conclusions: This implies that TLR agonists like imiquimod and gardiquimod could serve as neoadjuvant, adjuvant, or complementary immunotherapeutic agents in melanoma therapy. 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

In 2020, 128.5 million new chlamydia infections were reported worldwide in adults aged 15–49 years. Notably, the prevalence of Chlamydia trachomatis infection in pregnant women varies between 2% and 35%, correlating with increased risks of low birth weight, preterm birth, and neonatal death. C. trachomatis is a leading preventable cause of miscarriage. Recurrent first-trimester pregnancy loss can be induced by asymptomatic chlamydia infection through the immune response. In this study, we performed immunohistochemical characterization of the immune response in endometrial tissue biopsies from women diagnosed with chronic endometritis caused by C. trachomatis. Hematoxylin and eosin staining was used for histological evaluation of endometrial biopsies, and immunohistochemical detection was performed for the following markers: CD138, CD45, CD3, CD4, CD8, CD20, CD56, and CD68. As a result, we observed the presence of edematous tissue with hemorrhage; we also observed a heightened inflammatory response with the presence of plasma cells, CD4 and CD8 T lymphocytes, B lymphocytes, NK cells, and macrophages. The findings described here can help better understand the disease and its histopathological diagnosis. 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

Melatonin, an ancient and evolutionarily conserved indolamine, has long attracted attention for its multifunctional roles in redox homeostasis. More recently, it has been studied in relation to immune regulation and cancer biology. Beyond its well-known circadian function, melatonin modulates oxidative stress by directly scavenging reactive oxygen and nitrogen species and by upregulating antioxidant enzymes, including superoxide dismutase, catalase, and glutathione peroxidase. At the same time, it exerts wide-ranging immunomodulatory functions by influencing both innate and adaptive immune responses. All these actions converge within the tumor microenvironment, where oxidative stress and immune suppression drive cancer progression. Although the antitumoral effects of melatonin have traditionally been interpreted through its actions on T cells and NK cells, recent studies identify macrophages as an underappreciated and pivotal target. Notably, melatonin influences macrophage polarization, favoring antitumor M1 phenotypes over pro-tumoral M2 states, while attenuating chronic inflammation and restoring mitochondrial function. This review summarizes current knowledge on melatonin’s antioxidant and immunoregulatory mechanisms, highlighting its impact on the tumor immune microenvironment, with a particular focus on the growing recognition of macrophages as a compelling new axis through which melatonin may exert anticancer effects. Full article