A recombinant N2 neuraminidase-based CpG 1018® adjuvanted vaccine provides protection against challenge with heterologous influenza viruses in mice and hamsters.

Recombinant influenza virus neuraminidase (NA) is a promising broadly protective influenza vaccine candidate. However, the recombinant protein alone is not sufficient to induce durable and protective immune responses and requires the coadministration of immunostimulatory molecules. Here, we evaluated the immunogenicity and cross-protective potential of a recombinant influenza virus N2 neuraminidase vaccine construct, adjuvanted with a toll-like receptor 9 (TLR9) agonist (CpG 1018® adjuvant), and alum. The combination of CpG 1018 adjuvant and alum induced a balanced and robust humoral and T-cellular immune response against the NA, which provided protection and reduced morbidity against homologous and heterologous viral challenges in mouse and hamster models. This study supports Syrian hamsters as a useful complementary animal model to mice for pre-clinical evaluation of influenza virus vaccines.

Mitochondria Activity and CXCR4 Collaboratively Promote the Differentiation of CD11c+ B Cells Induced by TLR9 in Lupus.

Lupus is characterized by the autoantibodies against nuclear Ags, underscoring the importance of identifying the B cell subsets driving autoimmunity. Our research focused on the mitochondrial activity and CXCR4 expression in CD11c+ B cells from lupus patients after ex vivo stimulation with a TLR9 agonist, CpG-oligodeoxyribonucleotide (ODN). We also evaluated the response of CD11c+ B cells in ODN-injected mice. Post-ex vivo ODN stimulation, we observed an increase in the proportion of CD11chi cells, with elevated mitochondrial activity and CXCR4 expression in CD11c+ B cells from lupus patients. In vivo experiments showed similar patterns, with TLR9 stimulation enhancing mitochondrial and CXCR4 activities in CD11chi B cells, leading to the generation of anti-dsDNA plasmablasts. The CXCR4 inhibitor AMD3100 and the mitochondrial complex I inhibitor IM156 significantly reduced the proportion of CD11c+ B cells and autoreactive plasmablasts. These results underscore the pivotal roles of mitochondria and CXCR4 in the production of autoreactive plasmablasts.

A Multi-Functional Nanoadjuvant Coupling Manganese with Toll-Like 9 Agonist Stimulates Potent Innate and Adaptive Anti-Tumor Immunity.

The effectiveness of Toll-like 9 agonists (CpG) as an adjuvant for tumor immunotherapy is restricted due to their insufficient ability to activate anti-tumor immunity. To address that, the common nutrient metal ions are explored (Mn2+, Cu2+, Ca2+, Mg2+, Zn2+, Fe3+, and Al3+), identifying Mn2+ as a key enhancer of CpG to mediate immune activation by augmenting the STING-NF-κB pathway. Mn2+ and CpG are then self-assembled with epigallocatechin gallate (EGCG) into a nanoadjuvant MPN/CpG. Local delivery of MPN/CpG effectively inhibits tumor growth in a B16 melanoma-bearing mouse model, reshaping the tumor microenvironment (TME) by repolarizing M2-type tumor-associated macrophages (TAMs) to an M1-type and boosting intra-tumoral infiltration of CD8+/CD4+ T lymphocytes and DCs. Furthermore, compared to free CpG, MPN/CpG exhibits heightened accumulation in lymph nodes, enhancing CpG uptake and DC activation, consequently inducing significant antigen-specific cytotoxic CD8+ T cell immune response and humoral immunity. In a prophylactic tumor-bearing mouse model, MPN/CpG vaccination with OVA antigen significantly delays B16-OVA melanoma growth and extends mouse survival. These findings underscore the potential of MPN/CpG as a multifunctional adjuvant platform to drive powerful innate and adaptive immunity and regulate TME against tumors.

Bi-functional CpG-STAT3 decoy oligonucleotide triggers multilineage differentiation of acute myeloid leukemia in mice.

Acute myeloid leukemia (AML) cells resist differentiation stimuli despite high expression of innate immune receptors, such as Toll-like receptor 9 (TLR9). We previously demonstrated that targeting Signal Transducer and Activator of Transcription 3 (STAT3) using TLR9-targeted decoy oligodeoxynucleotide (CpG-STAT3d) increases immunogenicity of human and mouse AML cells. Here, we elucidated molecular mechanisms of inv(16) AML reprogramming driven by STAT3-inhibition/TLR9-activation in vivo. At the transcriptional levels, AML cells isolated from mice after intravenous administration of CpG-STAT3d or leukemia-targeted Stat3 silencing and TLR9 co-stimulation, displayed similar upregulation of myeloid cell differentiation (Irf8, Cebpa, Itgam) and antigen-presentation (Ciita, Il12a, B2m)-related genes with concomitant reduction of leukemia-promoting Runx1. Single-cell transcriptomics revealed that CpG-STAT3d induced multilineage differentiation of AML cells into monocytes/macrophages, erythroblastic and B cell subsets. As shown by an inducible Irf8 silencing in vivo, IRF8 upregulation was critical for monocyte-macrophage differentiation of leukemic cells. TLR9-driven AML cell reprogramming was likely enabled by downregulation of STAT3-controlled methylation regulators, such as DNMT1 and DNMT3. In fact, the combination of DNA methyl transferase (DNMT) inhibition using azacitidine with CpG oligonucleotides alone mimicked CpG-STAT3d effects, resulting in AML cell differentiation, T cell activation, and systemic leukemia regression. These findings highlight immunotherapeutic potential of bi-functional oligonucleotides to unleash TLR9-driven differentiation of leukemic cells by concurrent STAT3 and/or DNMT inhibition.

Defective endomembrane dynamics in Rab27a deficiency impairs nucleic acid sensing and cytokine secretion in immune cells.

Endosomal Toll-like receptors (eTLRs) are essential for the sensing of non-self through RNA and DNA detection. Here, using spatiotemporal analysis of vesicular dynamics, super-resolution microscopy studies, and functional assays, we show that endomembrane defects associated with the deficiency of the small GTPase Rab27a cause delayed eTLR ligand recognition, defective early signaling, and impaired cytokine secretion. Rab27a-deficient neutrophils show retention of eTLRs in amphisomes and impaired ligand internalization. Extracellular signal-regulated kinase (ERK) signaling and ß2-integrin upregulation, early responses to TLR7 and TLR9 ligands, are defective in Rab27a deficiency. CpG-stimulated Rab27a-deficient neutrophils present increased tumor necrosis factor alpha (TNF-α) secretion and decreased secretion of a selected group of mediators, including interleukin (IL)-10. In vivo, CpG-challenged Rab27a-null mice show decreased production of type I interferons (IFNs) and IFN-γ, and the IFN-α secretion defect is confirmed in Rab27a-null plasmacytoid dendritic cells. Our findings have significant implications for immunodeficiency, inflammation, and CpG adjuvant vaccination.

Serum TLR2 and TLR9 in Prostate Cancer Patients in Relation to EBV Status.

The relationship between Toll-like receptors (TLRs) and prostate cancer (PCa) is complex due to the presence of the Epstein-Barr virus (EBV) infection, which has been identified as a predisposing factor for some cancers, including PCa. The present study aims to investigate these complex links by examining the levels of selected TLRs and the potential impact of EBV infection on PCa. Therefore, we examined the serum of patients with PCa. The study compared EBV(+) patients to risk groups, the Gleason score (GS), and the T-trait. Additionally, the correlation between TLR and antibody levels was examined. The results indicated that higher levels of TLR-2 and TLR-9 were observed in more advanced PCa. The findings of this study may contribute to a deeper understanding of the role of viral infections in PCa and provide information on future strategies for the diagnosis, prevention, and treatment of these malignancies.

Revealing of TLR-9 gene polymorphisms by qPCR HRM technique and their influence on TLR-9 serum level in acute myeloid leukemia patients: Case-control study.

Acute myeloid leukemia (AML) is one of the most common and fatal malignancies that affect adults, which can quickly become aggressive if left untreated, and leukemia cells invade the bone marrow. TLR-9 is an innate immune cell receptor sensitive to various PAMPs and encoded by the TLR-9 gene. As is often known, genetic polymorphisms in any gene can help the development of the disease, and these three polymorphisms, rs187084, rs5743836, and rs352140 of TLR-9, have been studied in many different cancer disorders. Therefore, this study aimed to discover the multiple forms of a TLR-9 gene in a sample of Iraqi AML patients. A total of 120 participants in a case-control study were enrolled in the current study. Using CBC, some hematological parameters were evaluated, and the serum level of TLR-9 was assessed using the ELISA technique. DNA was extracted directly from blood, and a high-resolution melting (HRM) analysis was then carried out. The results revealed a significant difference in some blood parameters among patients and healthy control, while WBC and lymphocytes were without an evident difference between the two groups of the current investigation. The serum concentration of TLR-9 showed an elevated level in patients (P value < 0.01). Nonetheless, this increase was not affected by the genotype patterns of polymorphisms. According to the P-value, there was a significant difference in wild genotypes of the three polymorphisms (rs187084, rs5743836, and rs352140). At the same time, the odds ratio revealed the association with the disease as a protective factor. In contrast, there was a significant difference in the heterozygous and mutant genotypes of TLR-9 polymorphisms, though the odds ratio confirmed the association with the AML as a risk factor. The results of rs352140 were compatible with H.W.E since there were no significant differences between the observed and expected values for either patients or healthy controls. In contrast, the result of rs5743836 was not consistent with the HWE. Furthermore, although it corresponds with the healthy one, the finding of rs187084 conflicted with H.W.E. in the patient group. In conclusion, High serum levels of TLR-9 in patients could act as biomarkers for AML. The TLR-9 gene polymorphisms (rs187084, rs5743836, and rs352140) have been linked to an increased risk of AML and may impact the disease progression in the Iraqi population.

Gingival crevicular fluid levels of TLR-9, AIM-2, and ZBP-1 in periodontal diseases.

OBJECTIVES: Toll-like receptor (TLR)-9, may play a role in periodontal disease inflammation. This study measured TLR-9 and its related molecules, absence in melanoma-2 (AIM-2) and Z-DNA-binding protein-1 (ZBP-1), in gingival crevicular fluid (GCF) from patients with varying stages of periodontal disease to assess the role of pathogen-derived nucleic acids in inflammation. MATERIALS AND METHODS: The study comprised 80 participants: 20 with Stage III Grade C periodontitis, 20 with Stage III Grade B periodontitis (P-Stage III-B), 19 with gingivitis, and 21 with periodontal health. Parameters including probing depth (PD), clinical attachment level (CAL), plaque index (PI), and bleeding on probing (BOP) were recorded. ELISA was used to analyze TLR-9, AIM-2, and ZBP-1 levels in GCF. Nonparametric tests were used for statistical comparisons. RESULTS: The total amount of TLR-9 was higher in P-Stage III-B than in the healthy group (p < 0.05). Similarly, the gingivitis group exhibited elevated GCF TLR-9 levels compared to the healthy group (p < 0.05). GCF AIM-2 and ZBP-1 levels remained consistent across groups (p > 0.05). Significant correlations were found between GCF TLR-9 and CAL (p < 0.05), BOP (p < 0.05), PI (p < 0.01), and GCF volume (p < 0.001). CONCLUSION: These findings suggested that the TLR-9-mediated inflammatory process plays a role in periodontal disease, as evidenced by the increased levels of TLR-9 in GCF.

Plasmodium berghei TatD-like DNase hijacks host innate immunity by inhibiting the TLR9-NF-κB pathway.

Neutrophils and macrophages confine pathogens by entrapping them in extracellular traps (ETs) through activating TLR9 function. However, plasmodial parasites secreted TatD-like DNases (TatD) to counteract ETs-mediated immune clearance. We found that TLR9 mutant mice increased susceptibility to rodent malaria, suggesting TLR9 is a key protein for host defense. We found that the proportion of neutrophils and macrophages in response to plasmodial parasite infection in the TLR9 mutant mice was significantly reduced compared to that of the WT mice. Importantly, PbTatD can directly bind to the surface TLR9 (sTLR9) on macrophages, which blocking the phosphorylation of mitogen-activated protein kinase and nuclear factor-κB, negatively regulated the signaling of ETs formation by both macrophages and neutrophils. Such, P. berghei TatD is a parasite virulence factor that can inhibit the proliferation of macrophages and neutrophils through directly binding to TLR9 receptors on the cell surface, thereby blocking the activation of the downstream MyD88-NF-kB pathways.

Adenosine deaminase 2 regulates the activation of the toll-like receptor 9 in response to nucleic acids.

Human cells contain two types of adenosine deaminases (ADA) each with unique properties: ADA1, which is present in all cells where it modulates intracellular functions and extracellular signaling, and ADA2, which is secreted by immune cells. The exact intracellular functions of ADA2 remain undetermined and less defined than those of ADA1. ADA2 has distinct characteristics, such as low adenosine affinity, heparin-binding ability, and putative lysosomal entry. Here, we confirm that ADA2 is a lysosomal protein that binds toll-like receptor 9 (TLR9) agonists, specifically CpG oligodeoxynucleotides (CpG ODNs). We show that interferon-alpha (IFN-α) is secreted in response to TLR9 activation by CpG ODNs and natural DNA and markedly increases when ADA2 expression is downregulated in plasmacytoid dendritic cells (pDCs). Additionally, the pretreatment of pDCs with RNA further stimulates IFN-α secretion by pDCs after activation with CpG ODNs. Our findings indicate that ADA2 regulates TLR9 responses to DNA in activated pDCs. In conclusion, decreasing ADA2 expression or blocking it with specific oligonucleotides can enhance IFN-α secretion from pDCs, improving immune responses against intracellular infections and cancer.

Essential role of pre-existing humoral immunity in TLR9-mediated type I IFN response to recombinant AAV vectors in human whole blood.

Recombinant adeno-associated virus (AAV) vectors have emerged as the preferred platform for gene therapy of rare human diseases. Despite the clinical promise, host immune responses to AAV vectors and transgene remain a major barrier to the development of successful AAV-based human gene therapies. Here, we assessed the human innate immune response to AAV9, the preferred serotype for AAV-mediated gene therapy of the CNS. We showed that AAV9 induced type I interferon (IFN) and IL-6 responses in human blood from healthy donors. This innate response was replicated with AAV6, required full viral particles, but was not observed in every donor. Depleting CpG motifs from the AAV transgene or inhibiting TLR9 signaling reduced type I IFN response to AAV9 in responding donors, highlighting the importance of TLR9-mediated DNA sensing for the innate response to AAV9. Remarkably, we further demonstrated that only seropositive donors with preexisting antibodies to AAV9 capsid mounted an innate immune response to AAV9 in human whole blood and that anti-AAV9 antibodies were necessary and sufficient to promote type I IFN release and plasmacytoid dendritic (pDC) cell activation in response to AAV9. Thus, our study reveals a previously unidentified requirement for AAV preexisting antibodies for TLR9-mediated type I IFN response to AAV9 in human blood.

Therapeutic Effects of PEG-Modified Polyamide Amine Dendrimer for Cell Free DNA Adsorption in Temporomandibular Joint Osteoarthritis.

Temporomandibular joint osteoarthritis (TMJ OA) is characterized by the degeneration of cartilage and subchondral bone. In this study, we observed a significant increase in cell-free DNA (cfDNA) levels during the progression of TMJ OA. Bioinformatics analysis identified TLR9 as a pivotal molecule in TMJ OA pathogenesis. The polyamidoamine (PAMAM) dendrimer characterized by a well-structured, highly branched, and reactive nature, exhibits robust binding and clearance capabilities for cfDNA. However, the abundant amino groups on the surface of PAMAM lead to its inherent toxicity. To mitigate this, PEG-5000 was conjugated to the surface of PAMAM dendrimers, enhancing safety. Our results indicate that PEG-PAMAM effectively inhibits the upregulation of the TLR9 protein in TMJ OA, significantly suppressing the activation of the p-IκBα/p-NF-κB signaling pathway and subsequently decreasing chondrocyte inflammation and apoptosis, as evidenced by both in vivo and in vitro experiments. We conclude that PEG-PAMAM is a safe and effective material for in vivo applications, offering a promising therapeutic strategy for TMJ OA by targeting cfDNA clearance.

Low levels of supercoiled mitochondrial DNA are involved in heart failure induced by transverse aortic constriction in mice via an inflammatory response mediated by ZBP1.

BACKGROUND: Inflammation in the myocardium plays a critical role in cardiac remodeling and the pathophysiology of heart failure (HF). Previous studies have shown that mitochondrial DNA (mtDNA) can exist in different topological forms. However, the specific influence of the ratio of supercoiled/relaxed mtDNA on the inflammatory response in cardiomyocytes remains poorly understood. The aim of this study was to elucidate the differential effects of different mtDNA types on cardiomyocyte inflammation through regulation of ZBP1. MATERIALS AND METHODS: A mouse model of HF was established by transverse aortic constriction (TAC) or doxorubicin (Doxo) induction. Histopathological changes were assessed by HE staining. ELISA was used to measure cytokine levels (IL-1ß and IL-6). Southern blot analysis was performed to examine the different topology of mtDNA. Pearson correlation analysis was used to determine the correlation between the ratio of supercoiled/relaxed mtDNA and inflammatory cytokines. Reverse transcription quantitative PCR (RT-qPCR) was used to measure the mRNA expression levels of cytokines (IL-1ß, IL-6) and Dloop, as an mtDNA marker. RESULTS: The ratio of supercoiled to relaxed mtDNA was significantly increased in the myocardium of Doxo-induced mice, whereas no significant changes were observed in TAC-induced mice. The levels of IL-1ß and IL-6 were positively correlated with the cytoplasmic mtDNA supercoiled/relaxed circle ratio. Different mtDNA topology has different effects on inflammatory pathways. Low supercoiled mtDNA primarily activates the NF-κB (Ser536) pathway via ZBP1, whereas high supercoiled mtDNA significantly affects the STAT1 and STAT2 pathways. The RIPK3-NF-κB pathway, as a downstream target of ZBP1, mediates the inflammatory response induced by low supercoiled mtDNA. Knockdown of TLR9 enhances the expression of ZBP1, p-NF-κB, and RIPK3 in cardiomyocytes treated with low supercoiled mtDNA, indicating the involvement of TLR9 in the anti-inflammatory role of ZBP1 in low supercoiled mtDNA-induced inflammation. CONCLUSION: Different ratios of supercoiled to relaxed mtDNA influence the inflammatory response of cardiomyocytes and contribute to HF through the involvement of ZBP1. ZBP1, together with its downstream inflammatory mechanisms, mediates the inflammatory response induced by a low ratio of supercoiled mtDNA.

Characterization of the TLR9-Activating Potential of LNA-Modified Antisense Oligonucleotides.

Early characterization of the immunostimulatory potential of therapeutic antisense oligonucleotides (ASOs) is crucial. At present, little is known about the toll-like receptor 9 (TLR9)-mediated immunostimulatory potential of third-generation locked nucleic acid (LNA)-modified ASOs. In this study, we have systematically investigated the TLR9-activating potential of LNA-modified oligonucleotides using different mouse and human cell culture systems. Although it has been reported that LNA modifications as well as cytosine methylation of 5'-cytosine-phosphate-guanine-3' (CpG) motifs can reduce TLR9 stimulation by phosphorothioate (PTO)-modified oligonucleotides, we identified CpG-containing LNA gapmers with substantial TLR9-stimulatory activity. We further identified immunostimulatory LNA gapmers without CpG motifs. Unexpectedly, methylation of cytosines only within the CpG motif did not necessarily reduce but could even increase TLR9 activation. In contrast, systematic methylation of all cytosines reduced or even abrogated TLR9 activation in most cases. Context dependently, the introduction of LNA-modifications into the flanks could either increase or decrease TLR9 stimulation. Overall, our results indicate that TLR9-dependent immunostimulatory potential is an individual feature of an oligonucleotide and needs to be investigated on a case-by-case basis.

The Expression of Toll-like Receptors (TLR7 and TLR9) in Class III and Class IV of Recently Diagnosed Lupus Nephritis with 12-Month Follow-Up.

Renal involvement is an important cause of morbidity and mortality in systemic lupus erythematosus (SLE). The present study included patients with recently diagnosed Class III and Class IV lupus nephritis (LN) treated by Rheumatology who, upon the detection of alterations in their kidney function, were referred to Nephrology for the joint management of both medical specialties. The purpose of this study was to compare the plasma expression of Toll-Like Receptor 7 (TLR7) and TLR9 in healthy control (HC) subjects and newly diagnosed Class III and Class IV LN patients with 12-month follow-ups. The plasma expression of TLR7 and TLR9 proteins was determined by the ELISA method. A significant increase in the expression of TLR7 protein was found in Class III LN in the basal determination compared to the expression in the HC (p = 0.002) and at 12 months of follow-up (p = 0.03) vs. HC. The expression of TLR9 showed a behavior opposite to that of TLR7. TLR9 showed decreased protein expression in LN Class III patients' baseline and final measurements. The result was similar in the basal and final determinations of LN Class IV compared to the expression in HC. A significant decrease in SLEDAI -2K was observed at 12 months of follow-up in patients in Class III (p = 0.01) and Class IV (p = 0.0001) of LN. Complement C3 levels improved significantly at 12-month follow-up in Class IV patients (p = 0.0001). Complement C4 levels decreased significantly at 12-month follow-up in LN Class III compared to baseline (p = 0.01). Anti-DNA antibodies decreased significantly at 12 months of follow-up in Class IV LN (p = 0.01). A significant increase in proteinuria was found at 12 months of follow-up in Class III LN, compared to the baseline determination (p = 0.02). In LN Class IV, proteinuria decreased at 12 months of follow-up compared to baseline (p = 0.0001). Albuminuria decreased at 12 months of follow-up in LN Class IV (p = 0.006). Class IV LN, albuminuria also decreased at 12 months of follow-up (p = 0.009). Hematuria persisted in all patients and the glomerular filtration rate did not change. Three Class IV patients died before 12 months of follow-up from various causes. In conclusion, although the rheumatologic data appeared to improve, the renal function data remained inconsistent. Decreased expression of TLR9 and increased expression of TLR7 could be useful in the early diagnosis of Class III and Class IV LN is correct.

Functions and Clinical Relevance of Liver-Derived Immunoglobulins.

Liver is the largest internal organ of the body with vital functions. In addition to its endocrine and exocrine activities, liver also plays a pivotal role in the immune system, including haematopoietic functions. Liver parenchymal cells, which are epithelial cells, have been found to possess innate immune functions by expressing pattern-recognition receptors (PRRs), producing complement components, and secreting cytokines. Intriguingly, in recent years, it has been discovered that liver epithelial cells also produce immunoglobulins (Igs), which have long been thought to be produced exclusively by B cells. Notably, even liver epithelial cells from B lymphocyte-deficient mice, including SCID mice and µMT mice, could also produce Igs. Compelling evidence has revealed both the physiological and pathological functions of liver-derived Igs. For instance, liver epithelial cells-derived IgM can serve as a source of natural and specific antibodies that contribute to innate immune responses, while liver-produced IgG can act as a growth factor to promote cell proliferation and survival in normal hepatocytes and hepatocarcinoma. Similar to that in B cells, the toll-like receptor 9 (TLR9)-MyD88 signaling pathway is also actively involved in promoting liver epithelial cells to secrete IgM. Liver-derived Igs could potentially serve as biomarkers, prognostic indicators, and therapeutic targets in the clinical setting, particularly for liver cancers and liver injury. Nevertheless, despite significant advances, much remains unknown about the mechanisms governing Ig transcription in liver cells, as well as the detailed functions of liver-derived Igs and their involvement in diseases and adaptive immunity. Further studies are still needed to reveal these underlying, undefined issues related to the role of liver-derived Igs in both immunity and diseases.

Unveiling the role of mtDNA in Liver-Kidney Crosstalk: Insights from trichloroethylene hypersensitivity syndrome.

In specific pathological conditions, addressing liver injury may yield favorable effects on renal function through the phenomenon of liver-kidney crosstalk. Mitochondrial DNA (mtDNA) possesses the capability to trigger downstream pathways of inflammatory cytokines, ultimately leading to immune-mediated organ damage. Consequently, understanding the intricate molecular mechanisms governing mtDNA involvement in diseases characterized by liver-kidney crosstalk is of paramount significance. This study seeks to elucidate the role of mtDNA in conditions marked by liver-kidney crosstalk. In previous clinical cases, it has been observed that patients with Trichloroethylene Hypersensitivity Syndrome (TCE-HS) who experience severe liver injury often also exhibit renal injury. In this study, patients diagnosed with trichloroethylene hypersensitivity syndrome were recruited from Shenzhen Occupational Disease Control Center. And Balb/c mice were treated with trichloroethylene. The correlation between liver and kidney injuries in patients with TCE-HS was assessed using Enzyme-Linked Immunosorbent Assay (ELISA). Alterations in mtDNA levels were examined in mouse hepatocytes, red blood cells (RBCs), and renal tubular epithelial cells utilizing immunofluorescence and PCR techniques. TCE-sensitized mice exhibited a significant increase in reactive oxygen species (ROS) and the opening of the mitochondrial permeability transition pore in hepatocytes, resulting in the release of mtDNA. Furthermore, heightened levels of mtDNA and Toll-like Receptor 9 (TLR9) expression were observed in RBCs. Additional experiments demonstrated elevated expression of TLR9 and its downstream mediator MyD88 in renal tubule epithelial cells of TCE-sensitized mice. In vitro investigations confirmed that mtDNA activates the TLR9 pathway in TCMK-1 cells. Collectively, these results suggest that mtDNA released from mitochondrial damage in hepatocytes is carried by RBCs to renal tubular epithelial cells and mediates inflammatory injury in renal tubular epithelial cells through activation of the TLR9 receptor.

Investigation of TLR2 (-196 to -174del) and TLR9 (T-1486C) Gene Polymorphisms Association with Inflammatory Bowel Diseases.

BACKGROUND: Inflammatory bowel diseases (IBD), Crohn's disease (CD), and ulcerative colitis (UC) are diseases that result from the combined effects of a predisposing genetic background and several environmental factors, including smoking. Some genes can influence these diseases through genetic inheritance, and their regulation is explained by gene polymorphism. However, Toll-like receptor (TLR) genes have been identified as susceptibility genes for CD and UC. METHODS: A case-control study was performed on a Turkish population composed of 105 healthy controls and  79 CD, 77 UC patients genotyped by Allele-specific PCR and PCR-RFLP for TLR9 (T-1486C) and TLR 2 (-196 to -174del) gene. Genotype and allele frequencies of TLR9 (T-1486C) and TLR 2 (-196 to -174del) gene polymorphisms compared to allele frequencies in CD and UC patients. RESULTS: No statistically significant findings were found between the CD, UC patients, and the control group in terms of both genotype distributions and allele frequencies for TLR 9 (T-1486C; rs187084) and TLR 2 (-196 to -174del; rs111200466) gene polymorphisms in a Turkish population (P > 0.05). CONCLUSION: No association was found between the TLR2 (rs111200466) and TLR 9 (rs187084) gene polymorphisms among IBD patients and the control groups in the Turkish population.

Synergistic Effects of Metal-Organic Nanoplatform and Guanine Quadruplex-Based CpG Oligodeoxynucleotides in Therapeutic Cancer Vaccines with Different Tumor Antigens.

Oligodeoxynucleotides (ODNs) containing unmethylated cytosine-phosphate-guanosine (CpG) motifs are readily recognized by Toll-like receptor 9 on immune cells, trigger an immunomodulatory cascade, induce a Th1 -biased immune milieu, and have great potential as an adjuvant in cancer vaccines. In this study, a green one-step synthesis process was adopted to prepare an amino-rich metal-organic nanoplatform (FN). The synthesized FN nanoplatform can simultaneously and effectively load model tumor antigens (OVA)/autologous tumor antigens (dLLC) and immunostimulatory CpG ODNs with an unmodified PD backbone and a guanine quadruplex structure to obtain various cancer vaccines. The FN nanoplatform and immunostimulatory CpG ODNs generate synergistic effects to enhance the immunogenicity of different antigens and inhibit the growth of established and distant tumors in both the murine E.G7-OVA lymphoma model and the murine Lewis lung carcinoma model. In the E.G7-OVA lymphoma model, vaccination efficiently increases the CD4+, CD8+, and tetramer+CD8+ T cell populations in the spleens. In the Lewis lung carcinoma model, vaccination efficiently increases the CD3+CD4+ and CD3+CD8+ T cell populations in the spleens and CD3+CD8+, CD3-CD8+, and CD11b+CD80+ cell populations in the tumors, suggesting the alteration of tumor microenvironments from cold to hot tumors.