Leptin, a multifunctional hormone primarily secreted by adipose tissue, plays a crucial role in regulating body weight, appetite, energy expenditure, and metabolic processes. Beyond regulating metabolic pathways, leptin demonstrates notable immunoregulatory capabilities. It modulates a wide range of biological functions, including glycemic control, hematopoietic processes, and bone metabolism. The discovery of leptin has significantly advanced our understanding of the crosstalk between metabolic homeostasis and immune system functionality. Recent research highlights its critical role in immune responses, particularly in modulating T lymphocytes. This hormone transmits nutritional signals to the immune system, promoting pro-inflammatory Th1 and Th17 responses while inhibiting anti-inflammatory Treg cell proliferation. Consequently, it is a pivotal regulator integrating metabolic signals to control the balance between inflammation and immune tolerance. In this review, we will synthesize the latest advancements in leptin research, leptin receptor signaling, the hormone's impact on T cells and immune responses, as well as its potential pathogenic roles in autoimmune diseases, including Systemic Lupus Erythematosus (SLE), psoriasis, vitiligo, and other autoimmune disorders. Our objective is to provide a comprehensive analysis of leptin's properties and its unique roles in autoimmune conditions, with the aim of providing new insights into effective and holistic therapeutic strategies.
Metabolic reprogramming within the tumor microenvironment (TME) is a pivotal driver of CD8+ T cell dysfunction in cancer. Tumor cells outcompete T cells for essential nutrients, including glucose and amino acids, while accumulating immunosuppressive metabolites such as lactate and 2-hydroxyglutarate. Beyond direct functional impairment, emerging research reveals that these metabolic alterations orchestrate CD8+ T cell transcriptional programs by remodeling their epigenome-via histone modifications, DNA methylation, and non-coding RNA networks-thereby dictating their differentiation, cytotoxic potential, and memory formation. A deeper understanding of how TME-derived metabolic signals shape the epigenetic landscape of CD8+ T cells is crucial for improving current cancer immunotherapeutic strategies. This review systematically delineates how key TME metabolic features, including nutrient deprivation and oncometabolite accumulation, regulate CD8+ T cell fate through epigenetic pathways. Furthermore, we discuss promising therapeutic strategies that target the metabolism-epigenetics axis to reinvigorate CD8+ T cell anti-tumor immunity, offering novel perspectives for enhancing adoptive cell therapy and immune checkpoint blockade.
BACKGROUND:Cerebral malaria (CM) is a life-threatening neurological complication of Plasmodium falciparum infection characterized by excessive inflammation, blood-brain barrier (BBB) disruption, and immune dysregulation. Macrophage-mediated inflammatory responses play a central role in CM pathogenesis, where imbalanced activation contributes to disease progression and tissue damage. However, integrated analyses combining macrophage surface phenotyping with transcriptional profiling remain limited, restricting comprehensive understanding of immune modulation during CM. OBJECTIVE:To investigate the prophylactic immunomodulatory effects of MSCs administration in experimental CM and evaluate its impact on splenic macrophage responses. METHODS:C57BL/6 mice infected with Pb.ANKA received intravenous MSC administration on the day of infection and were monitored for parasitemia and survival. BBB integrity was assessed using Evans blue extravasation, and brain pathology was evaluated histologically. MSC biodistribution was analyzed using near-infrared labeling. Macrophage polarization in F4/80+CD11b+ splenic cells was assessed by flow cytometry using M1 markers (CD86, CD38) and M2 markers (CD163, CD206, EGR-2). Gene expression of macrophage-associated markers (iNOS-2, Arginase-1, FPR-1, GPR-18, PTGES-2, EGR-2) was analyzed by quantitative real-time PCR. RESULTS:MSC administration reduced parasitemia, improved survival, preserved BBB integrity, and attenuated brain pathology. MSCs showed systemic distribution, suggesting peripheral immune modulation. Flow cytometry revealed reduced M1 markers with maintained or enhanced M2 markers. Gene expression showed downregulation of iNOS-2 and upregulation of Arginase-1, EGR-2, GPR-18, FPR-1, and PTGES-2, indicating macrophage reprogramming toward a balanced M1/M2 continuum. CONCLUSION:MSC administration mitigates disease severity in experimental CM by modulating macrophage polarization, promoting a balanced M1/M2 response, attenuating inflammatory pathways, and preserving BBB integrity.
The gut represents a melting pot of distinct classes of antigens derived from self antigens, dietary components, and the commensal microbiota. To maintain tolerance to innocuous antigens while preserving the capacity to respond to potentially harmful microorganisms, the immune system has evolved tightly regulated mechanisms centered on the generation of Foxp3+ regulatory T (Treg) cells at mucosal surfaces. Although early insights into intestinal Treg development were largely derived from studies using model dietary antigens or selected microbial species, a substantial gap remains in our understanding of the natural antigen landscape that elicits Treg responses in vivo. In this review, we discuss recent advances based on TCR classification approaches that define intestinal Treg T cell receptor (TCR) responses according to in vivo antigen reactivity, and we highlight key future directions for elucidating the functional roles of antigen-presenting cell subsets and their associated peptide landscapes in shaping intestinal Treg biology.
Head and neck cancers (HNCs) pose a significant global health challenge, with treatment complexities and profound impacts on patient quality of life. Tumor-infiltrating B cells (TIBs) within the tumor microenvironment (TME) are emerging as critical yet dual regulators of HNC immunity, exhibiting both pro- and anti-tumorigenic properties. This manuscript explores the prognostic and predictive roles of TIBs across diverse HNCs, including squamous cell carcinomas and lymphomas. TIBs enhance antitumor immunity through antibody production, antigen presentation, and the formation of tertiary lymphoid structures (TLSs), which correlate with improved survival and response to immune checkpoint inhibitors (ICIs). Conversely, regulatory B cells contribute to immunosuppression, promoting tumor progression. Notably, high TIB infiltration, particularly within TLSs, is associated with superior outcomes in ICI-treated patients, highlighting their potential as biomarkers and therapeutic targets. However, challenges such as data variability and limited study scales underscore the need for further investigation into TIB subpopulations and their molecular dynamics. Future research should prioritize understanding TIB interactions with other immune cells and developing novel immunotherapies, including genetic engineering and oncolytic viruses, to advance HNC treatment and optimize patient outcomes.
Gamma-delta (γδ) T cells, which bridge innate and adaptive immunity, are attractive candidates for immunotherapy. Significant interspecies differences exist, particularly between humans and ruminants. In ruminants, γδ T cells are a major circulating population characterized by the Workshop Cluster 1 (WC1) family, a unique set of Scavenger Receptor Cysteine-Rich (SRCR) co-receptors. WC1 molecules function dually as pattern recognition receptors (PRRs) and essential co-stimulators for the γδ T cell receptor (TCR). Specific WC1 isoforms (e.g. WC1.1+, WC1.2+) are associated with distinct functional predispositions, within a broader functional plasticity observed in both human and murine γδ T cell subsets. This review compares human and ruminant γδ T cell biology, proposing the WC1 co-stimulatory system as a functional paradigm for next-generation human T cell therapies. "WC1-inspired" synthetic receptors could provide more physiological, sustained activation, potentially overcoming key therapeutic limitations such as antigen escape and severe toxicity. Despite translational challenges, including the lack of a direct human WC1 ortholog, the ruminant model provides a critical potential for designing more durable and context-responsive immunotherapies.
BACKGROUND:Analyses of the association between circulating inflammatory cytokine levels and polymyositis (PM) remains challenging because of the limitations of traditional observational studies. Therefore, we used Mendelian randomization (MR) to assess the causal relationship between the levels of 41 circulating inflammatory cytokines and the risk of PM. METHODS:Using pooled data from genome-wide association studies (GWASs), we performed two-way MR analyses on two individual samples containing data for circulating inflammatory modulators (n = 8,186) and PM (n = 213,264) in patients of European ancestry. We used a random-effects inverse variance-weighted (IVW) method for our primary analysis and performed sensitivity and multiplicity analyses using MR-Egger, weighted-median, MR pleiotropy residual sum and outlier (MR-PRESSO), and Cochran's Q tests. RESULTS:The results showed that decreased circulating levels of granulocyte colony stimulating factor (GCSF) were associated with an increased risk of PM with an odds ratio (OR) of 0.31 (95% confidence interval [CI]: 0.13-0.74, p = 0.009). PM was also associated with increased circulating levels of interleukin (IL)-13 and IL-7, with OR values of 1.03 (95% CI = 1.01-1.06, p = 0.012) and 1.03 (95% CI = 1.01-1.06, p = 0.018), respectively, and decreased circulating levels of IL-1RA (OR, 0.97; 95% CI: 0.94-0.99, p = 0.040). CONCLUSION:These findings suggest that GCSF plays an important role in the pathogenesis of PM and that PM also affects the expression of the cytokines IL-13, IL-7, and IL-1RA. Further studies are required to determine whether these biomarkers can be used to prevent or treat PM.
Exosomes (EXOs), membrane vesicles, have garnered significant attention in cancer treatments as a novel means by which cells communicate with each other. EXOs are recognized for their pathophysiological participation in cancer therapy and their role in immune activation. Moreover, extensive research has been conducted on EXOs-mediated cancer treatment, demonstrating significant potential for targeting cancer stem cells (CSCs). Dendritic cells (DCs), which orchestrate the immune response, have been extensively utilized in immunotherapy. Similar to other cells, DCs can release nanovesicles, predominantly EXOs. Significant attention has been directed toward dendritic cell-derived EXOs (DC-EXOs) as immunotherapeutic agents for cancer treatment. Like DCs, DC-EXOs possess chemicals that engage with immune cells, including costimulatory molecules and functional MHC-peptide complexes on their surface. DC-EXOs offer several benefits over cell-based immunotherapies that employ DCs, including the ability to facilitate immune cell-mediated tumor eradication. Tumor peptide-loaded d DC-EXOs have demonstrated efficacy in Phase I clinical studies; a Phase II clinical trial is underway. This study has examined the therapeutic potential of DC-EXOs for CSCs and various types of cancer. The advantages and disadvantages of this therapeutic method were also reviewed to augment the anticancer efficacy and targeting of DC-EXOs for prospective clinical application.
Hepatocellular carcinoma (HCC), the most common form of primary liver cancer, remains a major global health concern due to its high incidence and mortality rates. Although advances in surgery, chemotherapy, and radiotherapy have improved management, the prognosis for advanced-stage HCC remains poor. Immunotherapy has emerged as a transformative approach, aiming to harness and modulate the immune system to target malignant cells more effectively. This review provides an updated overview of immunotherapeutic strategies in HCC, highlighting key modalities such as immune checkpoint inhibitors (ICIs), neoantigen-based vaccines, and tumor mutational burden (TMB) as predictive biomarkers of treatment response. Particular attention is given to ICIs targeting PD-1/PD-L1 and CTLA-4 pathways, as well as novel immune targets under investigation to overcome therapeutic resistance. Despite encouraging clinical outcomes, significant challenges persist, including immune evasion mechanisms, limited response rates, treatment resistance, and the complexity of the immunosuppressive tumor microenvironment. Addressing these obstacles requires integrating genomic insights, artificial intelligence-driven biomarker discovery, and rational combinatorial strategies that pair ICIs with targeted agents, chemotherapy, or radiotherapy to enhance immune activation. Future directions emphasize the development of precision immunotherapy guided by molecular profiling and predictive biomarkers to improve patient stratification and treatment efficacy. This review consolidates current progress, identifies key limitations, and outlines emerging avenues to optimize the future landscape of HCC immunotherapy.
Osteoporosis is a skeletal disease that affects the microarchitecture and mineralization of the bone, reduces bone strength, and lowers bone mineral density (BMD). Post-menopausal osteoporosis (PMO), caused by estrogen deficiency, is the most common type of osteoporosis. Given the chronic nature of PMO, sustained prevention or treatment with targeted bone-specific therapies and comprehensive medical management is crucial. Long-term usage of bone-specific pharmaceutical treatment therapies that include osteoanabolic and anti-resorptive drugs has sparked questions about side effects and possible rebound occurrences following treatment termination. Therefore, new therapy approaches with fewer side effects are needed. Studies in the past decade have demonstrated that immunological factors are crucial in the onset and progression of PMO. Treg and Th17 cells have long been recognized as critical factors in maintaining bone homeostasis, mainly via regulating osteoclast differentiation. However, astonishing data from our recent studies have highlighted the significant role of Breg and Th9 cells in bone homeostasis regulation. Breg and Th9 cells directly influence the development of bone cells and also regulate the Treg-Th17 cell balance to maintain skeletal integrity. We propose that although the Treg-Th17 cell axis is undeniably important in the pathophysiology of osteoporosis, the dynamic interplay between Breg-Treg and Th9-Th17 cells may play an even more pivotal role. This broader immune network likely exerts a greater influence on bone homeostasis and the progression of osteoporosis. However, the interplay between Breg-Treg vs Th9-Th17 cell axis in PMO remains limited. This review summarizes the most recent developments regarding the Breg-Treg vs Th9-Th17 cell axis in PMO and discusses the potential novel therapeutic strategies to address this issue. Novel pathophysiological insights into the Breg-Treg-Th9-Th17 cell axis in bone metabolism may pave the way for improved diagnosis and transformative treatments for PMO.
Mitochondria serve as the powerhouses of living cells, supplying energy and essential building blocks for cellular activities. The immune system exhibits a dynamic and active characteristic within the body, wherein immune cells are constantly activated and primed for pathogens without causing harmful effects on the self-body. These characteristics necessitate that immune cells function effectively and correctly, supported by a sufficient energy supply and metabolism from the mitochondria. Mitochondrial dysfunction leads to immune dysregulation, resulting in inappropriate inflammation, autoimmunity, immunodeficiency, and hypersensitive responses, all of which contribute to the development of illness and disease. Recent studies on mitochondrial transfer in immune cells indicate that mitochondrial replacement could emerge as a promising tool for rectifying immune cell function. This review will emphasize the role of mitochondria in various immune cell types and explore how mitochondrial dysfunction can result in pathogenesis in different conditions. We also discuss the potential application of mitochondrial transfer and transplantation to- and from immune cells in the context of health and disease.
Extracellular vesicles (EVs), nano-sized particles enclosed by a lipid membrane, play a pivotal role in cell-to-cell communication as essential mediators in various biological processes and diseases. Despite their ability to interact with multiple targets, EVs notably demonstrate a high affinity for specialized cells within the extracellular environment, particularly mononuclear phagocytes. The interaction between EVs and mononuclear phagocytes significantly affects the profile of these cells. Several factors, including vesicle cargo, size, parental cell origin, involved receptors, and the specific endocytic pathway, influence EVs' consequences and subsequent responses. Key components of mononuclear phagocytes, monocytes and macrophages, play a crucial role in the innate immune system, contributing to tissue damage, repair, remodeling, inflammation, homeostasis maintenance, and disease progression. Despite extensive research on EVs in various health and disease contexts, their precise impact on mononuclear phagocytes remains incompletely understood. Therefore, this review explores EVs' role in modulating monocyte and macrophage profiles and functions across different scenarios. It emphasizes that EVs actively shape the phenotype of these mononuclear phagocytes to maintain homeostasis and regulatory functions, but also induce pro-inflammatory polarization in infectious diseases, systemic inflammation, and autoimmunity. Simultaneously, during neoplastic or tumor development, the EV-mononuclear phagocyte axis prompts imbalanced responses, combining pro- and anti-inflammatory outcomes. These findings confirm EVs as promising tools for therapeutic strategies to modulate mononuclear phagocyte functions in diverse pathological settings.
Inflammatory bowel disease (IBD) varies in prevalence globally. Recent rise in IBD cases mirrors evolving health landscape due to urbanization and lifestyle changes worldwide. Existing drugs for IBD include aminosalicylates, corticosteroids, Immunomodulators, biologics, JAK inhibitors, and antibiotics. Although these medications are effective in managing symptoms and remission, these present several with limitations. Side effects such as nausea, infections, and liver toxicity are common, and some patients may develop resistance or lose response over time. Additionally, biologics can be costly, and immunosuppressive drugs raise concerns about long-term safety along increased risk of infection. Importantly, approximately 10% to 30% of the IBD patients do not respond to conventional treatments such as corticosteroids, immunosuppressants, or biologic therapies. Research continues to explore new treatments to address these limitations and improve outcomes for individuals with IBD. This review is an attempt to critically evaluate the currently available treatments for IBD underlining their limitations, and the pressing demand for innovative strategies. Further, we delve into the rationale behind peptide-based therapies, emphasizing their potential to modulate inflammation and promote mucosal healing. The work also highlights promising outcomes from recent preclinical and clinical studies underscoring the pivotal role of peptides in IBD management.
Membranous nephropathy (MN), an autoimmune cause of adult nephrotic syndrome, is driven by podocyte-targeting antibodies against PLA2R/THSD7A. Current models fail to fully capture human disease progression. This review evaluates three transformative approaches: (1) Heterologous antibody-induced models enabling acute injury replication; (2) Antigen-driven immunization modeling adaptive immunity; and (3) GBF-on-Chip platforms mimicking filtration barrier dynamics. Collectively, they reveal complement-dependent and direct podocytotoxic injury mechanisms. While antibody-induced models offer rapid injury induction and high reproducibility, their transient phenotype cannot model chronic progression or immune tolerance breakdown. Antigen-driven models recapitulate adaptive immunity but face prolonged timelines and epitope targeting bias diverging from human IgG4 dominance. GFB-on-Chip systems excel in mechanistic dissection of podocyte injury but lack immune microenvironment integration and physiologically accurate glomerular architecture. This review synthesizes strategies for MN model development through antibody-podocyte interaction studies, critically evaluates the strengths of existing platforms, and discusses emerging technologies for probing disease mechanisms and accelerating therapeutic discovery.
Antibody-drug conjugates (ADCs) are produced by integrating the specificity of monoclonal antibodies with cytotoxic payloads. ADCs are vital biologics for breast cancer treatment where they not only exert direct cytotoxicity but also promote anti-tumor immune responses against breast cancers. In this review, the structure, mechanism of action, and the anti-tumor immune response properties of approved and emerging ADCs are presented and discussed. The FDA-approved ADCs include trastuzumab emtansine (T-DM1), sacituzumab govitecan (SG-Trop2), and trastuzumab deruxtecan (T-DXd), as well as two emerging ADCs, i.e. datopotamab deruxtecan (Dato-DXd) and ladiratuzumab vedotin (LV). Preclinical and clinical studies demonstrate their efficacy in multiple breast cancer subtypes (e.g. HER2+ and triple negative breast cancers). These ADCs exert anti-tumor activity through cytotoxic effects and immune responses primarily by recruiting and activating cytotoxic T cells. Moreover, combining ADCs with immune checkpoint inhibitors (ICIs) shows enhanced therapeutic outcomes. ADCs resistance is caused by heterogeneous target antigens expression, modified ADC processing including endocytosis and lysosomal trafficking, as well as upregulated drug-efflux pumps that decrease payload concentration intracellularly. Strategies to mitigate ADCs resistance include multi-target ADCs, and stability-enhancing linkers that also reduce off-target toxicities. ADCs continue to play key roles in breast cancer treatment, while next-generation ADCs may address current ADCs' limitations and resistance mechanisms.
BACKGROUND:Granulomatosis with polyangiitis (GPA) is an autoimmune condition. This study evaluated the relationship between CTLA4 gene polymorphisms, specifically rs231775, rs5742909, and rs3087243, and the risk of developing GPA. MATERIALS AND METHODS:A case-control study was conducted with 217 participants, 102 individuals diagnosed with GPA, and 115 control subjects. The high-resolution melting (HRM) technique was used to genotype these polymorphisms. RESULTS:For the rs231775 polymorphism, the combined frequencies of AG and GG genotypes suggested an increased risk for GPA. Additionally, the GPA group had a higher frequency of the G allele. Also, patients with GG and AG genotypes displayed elevated levels of certain laboratory indices. Regarding rs5742909, the combined frequencies of TC and TT genotypes were linked to a lower risk of GPA. Moreover, a significant increase in the frequency of the T allele was noted in the control group. Those with the CC genotype exhibited a notably higher incidence of specific laboratory indices and some clinical manifestations. Our study found no significant association between the rs3087243 variant and the risk of developing GPA, nor with clinical or laboratory parameters. CONCLUSION:The G allele of the rs231775 is associated with a heightened risk of developing GPA. Conversely, the T allele of the rs5742909 SNP offers a protective effect against GPA; however, the presence of the C allele positively correlates with some laboratory parameters and symptoms. Furthermore, the rs3087243 polymorphism does not seem to be linked to an increased risk of GPA.
Mycobacterium tuberculosis (M. tb) employs diverse virulence factors to evade immune defenses and persist intracellularly. The ESAT-6 secretion system-1 (ESX-1) type VII secretion system (T7SS) releases EsxA, EspA, and EspB, inducing phagosomal rupture and cytosolic access while triggering host defenses, including galectin recruitment and stress granule formation. To counteract host responses, M. tb utilizes phthiocerol dimycocerosates (PDIMs) to inhibit autophagy and LC3-associated phagocytosis (LAP) by suppressing NADPH oxidase (NOX2) recruitment and reactive oxygen species (ROS) production. Additionally, CspA blocks LC3 lipidation, impairing LAP activation and phagosome maturation. EsxG and EsxH interfere with ESCRT-mediated phagosomal repair, further enhancing intracellular survival. Cytosolic M. tb is ubiquitinated by host E3 ligases, marking it for selective autophagy (xenophagy), yet M. tb evades degradation by manipulating autophagic flux. Simultaneously, M. tb-derived DNA activates the cyclic GMP-AMP synthase-stimulator of interferon response cGAMP interactor 1 (CGAS-STING1) axis, leading to type I interferon (IFN) signaling and inflammasome activation, which drive IL-1B and IL-18 secretion, necrosis, and pyroptosis, facilitating bacterial dissemination. Additionally, exosomes released during infection disseminate bacterial components, modulating immune responses systemically. This review uniquely integrates current findings on the coordinated actions of ESX-1 T7SS and PDIMs in mediating phagosomal rupture and immune evasion, offering a unified framework for understanding M. tb's intracellular survival strategies. By bridging lipid- and protein-mediated virulence mechanisms and their impact on host autophagy, inflammasome activation, and phagosomal repair pathways, this work provides novel insights into therapeutic targets aimed at restoring host immune function.
The livers' ability to regenerate after injury has attracted the investigation of possible therapeutic targets for liver disease. Cells of the immune system are considered fundamental for the initiation, propagation, and termination of liver regeneration as they produce essential signaling molecules, such as cytokines, chemokines, and growth factors. Previous evidence mainly focused on macrophage involvement in liver regeneration, namely Kupffer cells which secrete mitogenic cytokines. However, recent evidence has implicated other immune cell subsets in liver regeneration including platelets, the complement system, dendritic cells, granulocytes, and innate and adaptive lymphocytes. The concurrent function of different immune cell subsets highlights functional redundancies between immune cells and the temporospatial dynamics of liver regeneration. In this review, we discuss our understanding of the role of immune cells in liver regeneration, recent advances and cellular targets identified for clinical therapy over the past decade.
B-cells are vital immune cells that differentiate into plasma cells to produce antibodies targeting specific antigens. They also act as Antigen Presenting Cells, displaying processed antigens on Major Histocompatibility Complex class-II molecules to activate helper T-cells. This process triggers immune response and memory development. B-cells have surface antigens crucial for their function, which are often overexpressed in B cell cancers, making them targets for therapies like Chimeric Antigen Receptor (CAR) T-cell therapy. However, the choice of antigen is crucial. Tumor associated antigens are common but can cause off-target effects, while tumor specific antigens are more specific but less common. Furthermore, the precise epitope on the antigen recognized by the CAR-T cells significantly influences activation, which can also depend on the epitope's distance from the B-cell membrane. To facilitate the identification of extracellular regions of tumor antigens for CAR interactions, this review models tumor antigen structures embedded in the lipid bilayer, analyzing their roles and functions. Specifically, the characterization of B-cell surface antigens, encompassing their structural features and their potential as targets for CAR-T therapy are discussed. Each antigen is meticulously examined to gain insights into their specific roles within B cell biology and their potential as therapeutic targets. In conclusion, this review highlights the importance of understanding B cell antigens for the development of effective CAR-T cell therapies. The insights into antigen structures and functions presented here can guide the selection of optimal targets and the design of CAR-T cells to combat B cell malignancies effectively.
BACKGROUND:T cells play a crucial role in immune responses and are involved in chronic diseases such as Type 2 Diabetes Mellitus (T2DM) and its complications, including Diabetic Nephropathy (DN). Among these, regulatory T cells (Treg) act as key regulators, while T helper 9 (Th9) cells, which produce IL-9, are essential in maintaining immune balance. METHODS:The study included 145 participants divided into four groups: T2DM with nephropathy (35), T2DM without nephropathy (35), non-diabetic chronic kidney disease (ND-CKD) (35), and healthy controls (35). Various assessments were conducted, including anthropometric measurements, biochemical analyses, gene expression analysis was performed using RT-qPCR to profile mRNA and miRNA expression levels, flow cytometry (immune cell populations), and cytokine analysis by ELISA. Statistical analyses were carried out using SPSS, jamovi, Orange Data Mining, and Excel, ensuring robust evaluation and interpretation of the data. RESULTS:Th9 cells correlated with IL-9 (r = 0.72, p < 0.01), and Treg cells with IL-10 (r = 0.68, p < 0.01). The Th9/Treg ratio significantly increased across groups (χ2 = 14.8, p < 0.001), with notable differences between HC and T2DM (p = 0.009) and HC and DN (p < 0.001). IL-9 (AUC = 0.880) and Th9/Treg ratio (AUC = 0.762) showed potential as DN diagnostic markers. PTEN levels were reduced in DN and ND-CKD (p < 0.001, p = 0.017), while MMP2, hsa-miR-21-5p, and hsa-miR-181b-5p were elevated in disease groups (all p < 0.001), correlating with renal markers. COL4A4 was higher in DN vs. HC (p = 0.004), with PTEN downregulation linked to immune imbalance and fibrosis. CONCLUSION:Our study unveils immune cell and cytokine intricacies in DN. The high Th9/Treg ratio in T2DM and DN suggests immune tolerance loss, potentially influencing DN development. IL-9 and IL-10 display diagnostic potential. The Th9/Treg ratio and IL-9 serves as a discriminative diagnostic marker, particularly in DN. These insights offer avenues for early DN diagnosis and management.
