Search Results (1,437)

Background: Anti-programmed death 1 receptor (PD-1) therapy is a promising treatment strategy for patients with unresectable advanced or recurrent gastric/gastroesophageal junction (G/GEJ) cancer. However, its response rate and survival benefits are still limited; an immunological analysis of the residual tumor after anti-PD-1 therapy would be important. Methods: We evaluated the clinical efficacy of tumor resection (TR) after chemotherapy or anti-PD-1 therapy in patients with unresectable advanced or recurrent G/GEJ cancer and analyzed the immune status of tumor microenvironment (TME) by immunohistochemistry using their surgically resected specimens. Results: Patients treated with TR after anti-PD-1 therapy had significantly longer survival compared to those treated with chemotherapy and anti-PD-1 therapy alone. Expression of human leukocyte antigen (HLA) class I and major histocompatibility complex (MHC) class II on tumor cells was markedly downregulated after anti-PD-1 therapy compared to chemotherapy. Furthermore, the downregulation of HLA class I may be associated with the activation of transforming growth factor-β signaling pathway in the TME. Conclusions: Immune escape from cytotoxic T lymphocytes may be induced in the TME in patients with unresectable advanced or recurrent G/GEJ cancer after anti-PD-1 therapy due to the downregulation of HLA class I and MHC class II expression on tumor cells. TR may be a promising treatment strategy for these patients when TR is feasible after anti-PD-1 therapy. Full article

The prostate gland, a male accessory reproductive organ, is regulated by hormonal inputs and autonomic innervation from the major pelvic ganglion. This study examined the effects of major pelvic ganglion denervation on prostate histology, immune cell infiltration, and systemic levels of prolactin, testosterone, and cytokines in rats. Male Wistar rats (300–350 g) were divided into groups receiving bilateral axotomy of the hypogastric nerve, the pelvic nerve, or both, alongside with a sham-operated control. After 15 days, the animals were killed, and prostate tissue was dissociated in DMEM medium containing DNase I and collagenase. The dissociated cells were stained with fluorochrome-conjugated antibodies, and cell characterization was performed using a flow cytometer. Hematoxylin and eosin (H&E) staining was used to analyze histological characteristics, while testosterone, prolactin, and interleukin levels were measured via ELISA. Histological analysis revealed inflammatory atypical hypertrophy e hiperplasia. Immunological assessments demonstrated increased leukocytes, T lymphocytes (CD4⁺ and CD8⁺), B lymphocytes, and macrophages following double nerve axotomy. Serum analyses showed elevated pro-inflammatory cytokines IL-1β, IL-6, and IFN-γ, as well as anti-inflammatory IL-10, in denervated animals. Hormonal assessments revealed significant increases in serum prolactin and testosterone levels after double axotomy. Loss of neural control may promote pathological prostate changes via inflammation and hormonal dysregulation, offering insights into neuroimmune and neuroendocrine mechanisms underlying prostate pathologies. Full article

Multiple sclerosis (MS) and allergic diseases, traditionally considered immunologically opposing entities, may share pathogenic mechanisms rooted in immune dysregulation. While MS is predominantly mediated by Th1 and Th17 responses and allergies by Th2 responses, emerging evidence suggests overlapping immunological pathways, including the involvement of histamine, regulatory T cells, and innate lymphoid cells. This review synthesizes current knowledge on the epidemiological and immunopathological associations between MS and allergies. Epidemiological studies have yielded inconsistent results, with some suggesting a protective role for respiratory and food allergies against MS onset, while others find no significant correlation. Clinical studies indicate that food allergies in adults may be associated with increased MS inflammatory activity, whereas childhood atopy might exert a protective effect. In addition, we review hypersensitivity reactions to disease-modifying treatments for MS, detailing their immunological mechanisms, clinical presentation, and management, including desensitization protocols where applicable. Finally, we explore how treatments for allergic diseases—such as clemastine, allergen immunotherapy, montelukast, and omalizumab—may modulate MS pathophysiology, offering potential therapeutic synergies. Understanding the interplay between allergic and autoimmune processes is critical for optimizing care and developing innovative treatment approaches in MS. Full article

Background/Objectives: While ART effectively suppresses HIV viremia, many PLWH exhibit persistent immune dysfunction. This study aimed to assess immune recovery and immune exhaustion (PD-1/PD-L1 expression) in newly diagnosed versus long-term ART-treated individuals. Methods: We analyzed 79 PLWH: 52 newly diagnosed individuals (12-month follow-up) and 27 long-term-treated patients (Ukrainian refugees). Flow cytometry was used to evaluate CD4+ and CD8+ counts, the CD4+/CD8+ ratio, and PD-1/PD-L1 expression on CD3+, CD4+, and CD19+ lymphocytes. ART regimen and HIV subtype were included as covariates in linear regression models. Results: At 12 months, CD4+ counts were similar between groups (median 596.5 vs. 621 cells/μL, p = 0.22), but newly diagnosed patients had higher CD8+ counts (872 vs. 620 cells/μL, p = 0.028) and a lower CD4+/CD8+ ratio (0.57 vs. 1.05, p = 0.0027). Immune exhaustion markers were significantly elevated in newly diagnosed individuals: CD4+ PD-1+ T cells (24.4% vs. 3.85%, p = 0.0002) and CD3+ PD-1+ T cells (27.3% vs. 12.35%, p < 0.0001). Linear regression confirmed group membership independently predicted higher CD3+ (β = +21.92, p < 0.001), CD4+ (β = +28.87, p < 0.0001), and CD19+ (β = +8.73, p = 0.002) percentages. Lipid parameters and SCORE2 did not differ significantly. Conclusions: Despite virologic suppression and CD4+ recovery, immune exhaustion markers remain elevated in newly diagnosed PLWH, suggesting incomplete immune normalization. Traditional parameters (CD4+ count and CD4+/CD8+ ratio) may not fully capture immune status, warranting broader immunologic profiling in HIV care. Full article

Disruption of the gut microenvironment is a hallmark of HIV infection, where regulatory T cells (Tregs) play a critical role in maintaining gut homeostasis. However, the mechanisms by which gut Tregs contribute to immune reconstitution failure in HIV-infected individuals remain poorly understood. In this study, we employed single-cell RNA sequencing (scRNA-seq) to analyze gut Treg populations across three cohorts: eight immunological responders (IRs), three immunological non-responders (INRs), and four HIV-negative controls (NCs). Our findings revealed that INRs exhibit an increased proportion of gut Tregs but with significant functional impairments, including reduced suppressive capacity and heightened apoptotic activity. Notably, these Tregs underwent metabolic reprogramming in INRs, marked by an upregulation of glycolysis-related genes and a downregulation of the oxidative phosphorylation (OXPHOS) pathway. Additionally, both the abundance of short-chain fatty acid (SCFA)-producing bacteria and SCFA concentrations were reduced in INRs. In vitro SCFA supplementation restored Treg function by enhancing suppressive capacity, reducing early apoptosis, and rebalancing cellular energy metabolism from glycolysis to OXPHOS. These findings provide a comprehensive characterization of gut Treg dysfunction in INRs and underscore the therapeutic potential of targeting gut Tregs through microbiota and metabolite supplementation to improve immune reconstitution in HIV-infected individuals. Full article

Aging is associated with complex immune dysfunction that contributes to the onset and progression of the “geriatric giants”, including frailty, sarcopenia, cognitive decline, falls, and incontinence. Central to these conditions is immunosenescence, marked by thymic involution, the loss of naïve T cells, T-cell exhaustion, impaired B-cell class switch recombination, and increased autoreactivity. Concurrently, innate immunity deteriorates due to macrophage, neutrophil, and NK cell dysfunction, while chronic low-grade inflammation—or “inflammaging”—amplifies systemic decline. Key molecular pathways such as NF-κB, mTOR, and the NLRP3 inflammasome mediate immune aging, interacting with oxidative stress, mitochondrial dysfunction, and epigenetic modifications. These processes not only impair infection control and vaccine responsiveness but also promote tissue degeneration and multimorbidity. This review explores emerging interventions—ranging from senolytics and immunonutrition to microbiome-targeted therapies and exercise—that may restore immune homeostasis and extend healthspan. Despite advances, challenges remain in translating immunological insights into clinical strategies tailored to older adults. Standardization in microbiome trials and safety optimization in senolytic therapies are critical next steps. Integrating geroscience into clinical care could help to mitigate the burden of aging-related diseases by targeting fundamental drivers of immune dysfunction. Full article

Background: Understanding the duration and quality of immune memory following SARS-CoV-2 infection and vaccination is critical for informing public health strategies and vaccine development. While waning antibody levels have raised concerns about long-term protection, the persistence of memory B cells (MBCs) and T cells plays a vital role in sustaining immunity. Materials and Methods: We conducted a longitudinal prospective study over 12 months, enrolling 285 participants in total, either after natural infection or vaccination with BNT162b2 or mRNA-1273. Peripheral blood samples were collected at four defined time points (baseline, 1–2 months, 6–7 months, and 12–13 months after vaccination or disease onset). Immune responses were assessed through serological assays quantifying anti-RBD IgG and neutralizing antibodies, B-ELISPOT, and multiparameter flow cytometry for S1-specific memory B cells. Results: Both mRNA vaccines induced robust B cell and antibody responses, exceeding those observed after natural infection. Memory B cell frequencies peaked at 6 months and declined by 12 months, but remained above the baseline. The mRNA-1273 vaccine elicited stronger and more durable humoral and memory B-cell-mediated immunity compared to BNT162b2, likely influenced by its higher mRNA dose and longer prime-boost interval. Class-switched memory B cells and S1-specific B cells were significantly expanded in vaccine recipients. Natural infection induced more heterogeneous immune memory. Conclusions: Both mRNA vaccination and natural SARS-CoV-2 infection induce a comparable expansion of memory B cell subsets, reflecting a consistent pattern of humoral immune responses across all studied groups. These findings highlight the importance of vaccination in generating sustained immunological memory and suggest that the vaccine platform and dosage influence the magnitude and durability of immune responses against SARS-CoV-2. Full article

Despite targeting mainly the respiratory tract, SARS-CoV-2 disrupts T cell homeostasis in ways that may explain both acute lethality and long-term immunological consequences. In this study, we aimed to evaluate the T-cell-mediated chain of immunity and formation of TCR via TREC assessment in COVID-19 and long COVID (LC). For this study, we collected 231 blood samples taken from patients with acute COVID-19 (n = 71), convalescents (n = 51), people diagnosed with LC (n = 63), and healthy volunteers (n = 46). With flow cytometry, we assessed levels of CD4+ and CD8+ minor T cell subpopulations (i.e., naïve, central and effector memory cells (CM and EM), Th1, Th2, Th17, Tfh, Tc1, Tc2, Tc17, Tc17.1, and subpopulations of effector cells (pE1, pE2, effector cells)). Additionally, we measured TREC levels. We found distinct changes in immune cell distribution—whilst distribution of major subpopulations of T cells was similar between cohorts, we noted that COVID-19 was associated with a decrease in naïve Th and CTLs, an increase in Th2/Tc2 lymphocyte polarization, an increase in CM cells, and a decrease in effector memory cells 1,3, and TEMRA cells. LC was associated with naïve CTL increase, polarization towards Th2 population, and a decrease in Tc1, Tc2, Em2, 3, 4 cells. We also noted TREC correlating with naïve cells subpopulations. Our findings suggest ongoing immune dysregulation, possibly driven by persistent antigen exposure or tissue migration of effector cells. The positive correlation between TREC levels and naïve T cells in LC patients points to residual thymic activity. The observed Th2/Th17 bias supports the hypothesis that LC involves autoimmune mechanisms, potentially driven by molecular mimicry or loss of immune tolerance. Full article

Background: Regulatory T cells (Tregs) are the main suppressor cells that maintain immune tolerance and prevent autoimmunity. Changes in Treg number or function are implicated in a wide range of autoimmune and inflammatory (AI/I) diseases, with or without underlying inborn errors of immunity (IEI). Understanding the phenotypic profiles of Treg subsets and their associations with immune dysregulation is crucial to identifying potential robust and holistic biomarkers for disease activity. Methods: We examined peripheral blood mononuclear cells from 40 patients diagnosed with various autoimmune/inflammatory diseases, including those with genetically confirmed inborn errors of immunity (IEIs), and compared these samples to those from 38 healthy controls of the same age. Utilizing multiparametric flow cytometry, we measured multiple Treg sub-populations and investigated their correlations with lymphocyte subset profiles and the diversity of autoantibodies. We applied advanced statistical and machine learning techniques, such as t-SNE, k-means clustering, and ROC analysis, to analyze immunophenotypic patterns in the patients. Results: Among all Treg sub-populations, only CD4⁺CD127^lowCD25^highFOXP3⁺ Tregs showed a significant decrease in patients compared to healthy controls (p < 0.05), while other Treg phenotypes did not differ. FOXP3 expression showed reduced intensity in patients and demonstrated diagnostic potential (AUC = 0.754). Notably, this Treg subset negatively correlated with CD19⁺ B cell percentages and positively correlated with the diversity of circulating autoantibodies. Unsupervised clustering revealed three distinct immunophenotypic profiles, highlighting heterogeneity among patients and underlining FOXP3-centered immune dysregulation. Conclusions: Our results presented that patients have an impairment in the CD4⁺CD127^lowCD25^highFOXP3⁺ regulatory T cell subset, which is identified by significantly decreased frequency and decreased expression of FOXP3. Immunological heterogeneity among patients was further uncovered by unsupervised clustering, highlighting the critical role that FOXP3-centered regulatory failure plays in the pathophysiology of illness. The combined evaluation of these three immunological factors, centered around FOXP3, holds promise as an integrative tool for monitoring disease progression across various autoimmune and immunodeficient contexts. Full article

Background: Mycosis fungoides (MF), the most prevalent cutaneous T cell lymphoma, features clonal CD4⁺ T cell proliferation within a Th2-dominant microenvironment. Interleukin-4 (IL-4) promotes disease progression while Brentuximab Vedotin (BV), an anti-CD30 antibody–drug conjugate, shows efficacy but faces resistance challenges. Methods: We conducted a narrative literature review (2010–2024) synthesizing evidence on IL-4 signaling and BV’s efficacy in MF to develop a theoretical framework for combination therapy. Results: IL-4 may modulate CD30 expression and compromise BV’s effectiveness through immunosuppressive microenvironment remodeling. Theoretical mechanisms suggest that IL-4 pathway inhibition could reprogram the microenvironment toward Th1 dominance and restore BV sensitivity. However, no direct experimental evidence validates this combination, and safety concerns including potential disease acceleration require careful evaluation. Conclusions: The proposed IL-4/BV combination represents a biologically compelling but unproven hypothesis requiring systematic preclinical validation and biomarker-driven clinical trials. This framework could guide future research toward transforming treatment approaches for CD30-positive MF by targeting both malignant cells and their immunologically permissive microenvironment. Full article

The Gliomas account for 81% of all malignant central nervous system tumors and are classified by WHO into four grades of malignancy. Glioblastoma multiforme (GBM), the most common grade IV glioma, exhibits an extremely aggressive phenotype and a dismal five-year survival rate of only 6%, underscoring the urgent need for novel therapeutic approaches. Immunotherapy has emerged as a promising strategy, and photodynamic therapy (PDT) in particular has attracted attention for its dual cytotoxic and immunostimulatory effects. In GBM models, PDT induces immunogenic cell death characterized by the release of damage-associated molecular patterns (DAMPs), which promote antigen presentation and activate T cell responses. Additionally, PDT transiently increases blood–brain barrier permeability, facilitating immune cell infiltration into the tumor microenvironment, and enhances clearance of waste products via stimulation of meningeal lymphatic vessels. Importantly, PDT can reprogram or inactivate immunosuppressive tumor-associated macrophages, thereby counteracting the pro-tumoral microenvironment. Despite these encouraging findings, further preclinical and clinical studies are required to elucidate PDT’s underlying immunological mechanisms fully and to optimize treatment regimens that maximize its efficacy as part of integrated immunotherapeutic strategies against GBM. Full article

Human cytomegalovirus (HCMV) establishes lifelong latency in the host, with the bone marrow (BM) CD34+ cells serving as a key reservoir. To investigate tissue-specific immune responses to CMV, we analysed paired peripheral blood mononuclear cells (PBMCs) and bone marrow mononuclear cells (BMMNCs) from HCMV-seropositive donors using multiparametric flow cytometry and cytokine FluroSpot assays. We assessed immune cell composition, memory T cell subsets, cytokine production, cytotoxic potential, activation marker expression, and checkpoint inhibitory receptor (CIR) profiles, both ex vivo and following stimulation with lytic and latent HCMV antigens. BMMNCs were enriched in CD34+ progenitor cells and exhibited distinct T cell memory subset distributions. HCMV-specific responses were compartmentalised: IFN-γ responses predominated in PBMCs following lytic antigen stimulation, while IL-10 and TNF-α responses were more prominent in BMMNCs, particularly in response to latent antigens. US28-specific T cells in the BM showed elevated expression of CD39, PD-1, BTLA, CTLA-4, ICOS, and LAG-3 on CD4+ T cells and increased expression of PD-1, CD39, BTLA, TIGIT, LAG-3, and ICOS on CD8+ T cell populations, suggesting a more immunoregulatory phenotype. These findings highlight functional and phenotypic differences in HCMV-specific T cell responses between blood and bone marrow, underscoring the role of the BM niche in shaping antiviral immunity and maintaining viral latency. Full article

Background: Personalized anti-tumor therapy that activates the immune response has demonstrated clinical benefits in various cancers. However, its efficacy against testicular cancer (TC) remains uncertain. This study aims to identify suitable patients for anti-tumor immunotherapy and to uncover potential therapeutic targets in TC for the development of tailored anti-tumor immunotherapy. Methods: Consensus clustering analysis was conducted to delineate immune subtypes, while weighted gene co-expression network analysis (WGCNA), least absolute shrinkage and selection operator (LASSO) regression, and support vector machine (SVM) algorithms were employed to evaluate the potential efficacy of anti-tumor immunotherapy. Candidate immunotherapy targets were systematically identified through multi-gene panel analyses and subsequently validated using molecular biology assays. A prioritized target emerging from cellular screening was further evaluated for its capacity to potentiate anti-tumor immunity. The therapeutic efficacy of this candidate was rigorously confirmed through a comprehensive suite of immunological experiments. Results: Following systematic screening of five candidate genes (WNT11, FAM181B, GRK5, FSCN1, and ECHS1), GRK5 emerged as a promising therapeutic target for immunotherapy based on its distinct functional and molecular associations with immune evasion mechanisms. Cellular functional assays revealed that GRK5 knockdown significantly attenuated the malignant phenotype of testicular cancer cells, as evidenced by reduced proliferative capacity and invasive potential. Complementary immunological validation established that specific targeting of GRK5 with the selective antagonist GRK5-IN-2 disrupts immune evasion pathways in testicular cancer, as quantified by T-cell-mediated cytotoxicity. Conclusions: These findings position GRK5 as a critical modulator of tumor-immune escape, warranting further preclinical exploration of GRK5-IN-2 as a candidate immunotherapeutic agent. Full article

Immunological factors have gained growing recognition as key contributors to recurrent pregnancy loss (RPL) after in vitro fertilization (IVF), representing a major challenge in reproductive medicine. RPL affects approximately 1–2% of women trying to conceive naturally and up to 10–15% of those undergoing IVF, where overall success rates remain around 30–40% per cycle. An imbalance in maternal immunological tolerance toward the semi-allogeneic fetus during pregnancy may lead to miscarriage and implantation failure. IVF-related ovarian stimulation and embryo modification offer additional immunological complications that can exacerbate existing immune dysregulation. Recent advances in reproductive immunology have significantly deepened our understanding of the immune mechanisms underlying RPL following IVF, particularly highlighting the roles of regulatory T cells (T regs), natural killer cells, cytokine dysregulation, and disruptions in maternal–fetal immune tolerance. In order to better customize therapies, this evaluation incorporates recently discovered immunological biomarkers and groups patients according to unique immune profiles. Beyond conventional treatments like intralipid therapy and intravenous immunoglobulin, it also examines new immunomodulatory medications that target certain immune pathways, such as precision immunotherapies and novel cytokine modulators. We also discuss the debates over immunological diagnostics and therapies, such as intralipid therapy, intravenous immunoglobulin, corticosteroids, and anticoagulants. The heterogeneity of patient immune profiles combined with a lack of strong evidence highlights the imperative for precision medicine to improve therapeutic consistency. Novel indicators for tailored immunotherapy and emerging treatments that target particular immune pathways have encouraging opportunities to increase pregnancy success rates. Improving management approaches requires that future research prioritize large-scale clinical trials and the development of standardized immunological assessments. This review addresses the immunological factors in RPL during IVF, emphasizing underlying mechanisms, ongoing controversies, and novel therapeutic approaches to inform researchers and clinicians. Full article

Immunotherapy has emerged as a key modality in cancer treatment, yet its effectiveness varies significantly among patients, often due to the metabolic stress imposed by the tumor microenvironment. Hypoxia, a major factor in the tumor microenvironment, results from the high metabolic rate of tumor cells and inadequate vascularization, impairing immune cells’ function and potentially influencing gene expression profiles. Despite the widespread use of quantitative real-time PCR in immunological studies, to the best of our knowledge, data on reference gene stability in human peripheral blood mononuclear cells under hypoxic conditions is limited. In our study, we assessed the expression stability of commonly used reference genes (S18, HPRT, IPO8, RPL13A, SDHA, PPIA, and UBE2D2) in both non-stimulated and CD3/CD28-activated peripheral blood mononuclear cells cultured under normoxic, hypoxic (1% O₂), and chemically induced hypoxic conditions for 24 h. Analysis using four different algorithms—delta Ct, geNorm, NormFinder, and BestKeeper—identified RPL13A, S18, and SDHA as the most suitable reference genes for human peripheral blood mononuclear cells under hypoxic conditions. In contrast, IPO8 and PPIA were found to be the least suitable housekeeping genes. The study provides essential insights into the stability of reference genes in peripheral blood mononuclear cells under hypoxic conditions, a critical but understudied aspect of immunological research. Given the significant impact of hypoxia on T cell metabolism and function in the tumor microenvironment, selecting reliable reference genes is crucial for accurate gene expression analysis. Our findings will be valuable for future studies investigating hypoxia-driven metabolic reprogramming in immune cells, ultimately contributing to a better understanding of T cell responses in cancer immunotherapy. Full article