Variety of endosomal TLRs and Interferons (IFN-α, IFN-ß, IFN-γ) expression profiles in patients with SLE, SSc and MCTD.

We investigated Toll-like receptor (TLR)-3/-7/-8/-9 and interferon (IFN)-α/ß/γ mRNA expression in whole blood and serum IFN-α/ß/γ levels in patients with mixed connective tissue disease (MCTD), systemic lupus erythematosus (SLE) and systemic sclerosis (SSc) and in healthy subjects to assess the association between the TLR-IFN expression and severity of and susceptibility to diseases, and identify potential biomarkers. Expression of the IFN-γ, TLR-3 and TLR-8 was detected only in SLE patients. TLR-7, IFN-α and IFN-ß expression was highest in SLE, while TLR-9 expression was highest in SSc patients. In SLE and MCTD patients a strong correlation was observed between TLR-7 and IFN-α expression and IFN-ß and IFN-α expression. In MCTD patients, negative correlation between IFN-α and TLR-9 and TLR-7 and TLR-9 was revealed. TLR-9 expression in anti-U1-70k-negative, anti-C negative and anti-SmB-negative MCTD patients was higher than in MCTD-positive patients. We observed negative correlations between serum IFN-α levels and TLR-7 expression and C3 and C4 levels in SLE patients. In SLE patients we observed that with increased IFN-γ, TLR-3 and TLR-8 expression increased the value of C3 and C4. Our results confirmed that the endosomal TLR-IFN pathway seems to be more important in SLE than in MCTD or SSc, and that IFN-α and IFN-ß may be possible biomarkers for SLE.

Effect of Papaya Leaves (Carica papaya L.) Extract on Immune Response (TLR-7, TLR-9) and Inflammation (COX-2) in Rats Induces DMBA (7,12-Dimethylbenz[a]antrasen).

BACKGROUND AND OBJECTIVE: TLR is known to regulate the immune system in cancer. TLR-7 and TLR-9 can enhance the antitumor immune system in many types of solid tumors. Cyclooxygenase-2 (COX-2) is a biomarker of inflammation. This study aimed to investigate the effect of papaya leaves extract on immune response (TLR 7, TLR 9) and inflammation (COX-2) in rats induced DMBA. MATERIALS AND METHODS: This experimental study used Sprague dawley female rats of age more less 50 days. Rats were divided into 4 groups: Negative Control (NC), Positive Control (PC), Cancer Drug Doxorubicin (DOXO) and Papaya Leaves Extract (PLE). The study was conducted for 13 weeks. DMBA induction performed for 5 weeks with administration of 2 times per week. RESULTS: the expression of TLR-7 of PLE and DOXO was higher than PC groups significantly different (p<0.05). The expression of TLR-9 of PLE was higher than NC, PC and DOXO groups but not significantly different (p>0.05) while the expression of COX-2 of PLE and DOXO groups was lower than NC and PC groups but not significantly different (p>0.05). CONCLUSION: It can be concluded that papaya leaves extract can improve the immune system and reduce inflammation. It shows that papaya leaves extract has potent as anti-cancer.

Toll-like receptor 9 and the inflammatory response to surgical trauma and cardiopulmonary bypass.

OBJECTIVES: Cardiac surgery can lead to post-operative end-organ complications secondary to activation of systemic inflammatory response. We hypothesize that surgical trauma or cardiopulmonary bypass (CPB) may initiate systemic inflammatory response via release of mitochondrial DNA (mtDNA) signaling Toll-like receptor 9 (TLR9) and interleukin-6 production (IL-6). MATERIALS AND METHODS: The role of TLR9 in systemic inflammatory response in cardiac surgery was studied using a murine model of sternotomy and a porcine model of sternotomy and CPB. mtDNA and IL-6 were measured with and without TLR9-antagonist treatment. To study ischemia-reperfusion injury, we utilized an ex-vivo porcine kidney model. RESULTS: In the rodent model (n = 15), circulating mtDNA increased 19-fold (19.29 ± 3.31, p < 0.001) and plasma IL-6 levels increased 59-fold (59.06 ± 14.98) at 1-min post-sternotomy compared to pre-sternotomy. In the murine model (n = 11), administration of TLR-9 antagonists lowered IL-6 expression post-sternotomy when compared to controls (59.06 ± 14.98 vs. 5.25 ± 1.08) indicating that TLR-9 is a positive regulator of IL-6 after sternotomy. Using porcine models (n = 10), a significant increase in circulating mtDNA was observed after CPB (Fold change 29.9 ± 4.8, p = 0.005) and along with IL-6 following renal ischaemia-reperfusion. Addition of the antioxidant sulforaphane reduced circulating mtDNA when compared to controls (FC 7.36 ± 0.61 vs. 32.0 ± 4.17 at 60 min post-CPB). CONCLUSION: CPB, surgical trauma and ischemic perfusion injury trigger the release of circulating mtDNA that activates TLR-9, in turn stimulating a release of IL-6. Therefore, TLR-9 antagonists may attenuate this response and may provide a future therapeutic target whereby the systemic inflammatory response to cardiac surgery may be manipulated to improve clinical outcomes.

Toll-like receptor 9 negatively related to clinical outcome of AML patients.

BACKGROUND: Acute myeloid leukemia (AML) can modulate toll-like receptor-9 (TLR9) expression and activation. This study was conducted to elucidate the expression of TLR9 in AML patients and its relation to the prognosis of the disease. RESULTS: The study included 40 newly diagnosed AML patients managed in the hospital in addition to 20 sex and age matched normal volunteers as control. TLR9 expression assay was conducted on peripheral blood samples of AML cases before the start of treatment as well as the controls by immunophenotyping. TLR9 expression was ranging from 0.10 to 2.40% in AML patients with higher expression among the control, ranging from 0.94 to 8.25%. The median TLR9 expression in AML patients was significantly lower with advanced cytogenetic risk score. It is not significantly differing in relation to patients' sex, age group, and FAB type of AML. However, significant lower median expression was found in relation to clinical outcome. TLR9 expression ≤ 1% showed lower median overall survival time when compared to those with > 1% expression. CONCLUSION: This study concluded that AML patients express TLR9 in leukemic cells with very low percentage. This expression was negatively related to the clinical outcome.

Toll-like receptor 2 and 9 expression on circulating neutrophils is associated with increased mortality in critically ill patients.

BACKGROUND: Toll-like receptors (TLRs) play an important role in inflammatory processes in critically ill patients by binding to pathogen-associated molecular patterns and danger-associated molecular patterns (DAMPs). Whether neutrophil or monocyte TLR expression patterns are associated with outcome in critical illness is unknown. OBJECTIVES: To answer this question, we conducted a prospective, observational study including 215 consecutive patients admitted to a medical ICU at a tertiary care center. METHODS: Blood was drawn at admission and expression of TLR-2, TLR-4, and TLR-9 on neutrophils and monocytes were analyzed by flow cytometry. RESULTS: Median Acute Physiology and Chronic Health Evaluation II (APACHE II) score was 19, and 30-day mortality was 26%. TLR-2 expression on neutrophils was associated with APACHE II, Simplified Acute Physiology Score II, and Sepsis-related Organ Failure Assessment score. TLR-2 (P < 0.001) and TLR-9 (P < 0.05) expression on neutrophils was significantly higher in nonsurvivors. In contrast, neutrophil TLR-4 expression and monocyte TLR expression were not associated with survival. Neutrophil TLR-2 (odds ratio 3.8; 95% confidence interval 1.4-10.2; P < 0.05) and TLR-9 (odds ratio 4.0; 95% confidence interval 2.0-8.1; P < 0.001) expression in the third tertile predicted mortality independent from APACHE II, serum lactate, serum creatinine, and procalcitonin, respectively. CONCLUSION: We provide evidence for prognostic properties of neutrophil TLR-2 and TLR-9 expression regarding 30-day mortality in unselected critically ill patients, independent from baseline clinical characteristics, and laboratory values. These findings suggest that specific TLR-dependent activation of the innate immune system via neutrophils possibly caused by cell damage and release of otherwise intracellular components may play a significant role in the pathophysiology of critical illness.

[Role of TLR 9 expression in maternal peripheral blood and placenta in intrauterine transmission of HBV].

Objective: To explore the role of TLR 9 in intrauterine transmission of hepatitis B virus (HBV) through blood pathway and placenta. Methods: Epidemiological investigation was carried out in 290 HBsAg positive parturients and 45 normal parturients (control group) in Northwest Women and Children Hospital of Shaanxi Province. Enzyme-linked immunosorbent assay (ELISA) was used to detect five serological makers of hepatitis B and TLR 9 levels in peripheral blood of pregnant women and newborns. HBV DNA was detected by real-time fluorescence quantitative PCR. Detection of TLR 9 expression in placenta by immunohistochemical method. A case-control study was conducted to analyze the difference of TLR 9 levels in placenta and peripheral blood of HBsAg- positive pregnant women with intrauterine transmission of HBV. Results: The incidence of dominant HBV infection (DBI), occult HBV infection (OBI) and intrauterine transmission of HBV were 9.28% (27/291), 40.21% (117/291) and 49.48% (144/291) respectively. (1) The level of TLR 9 in peripheral blood of HBsAg-positive parturients, non-HBV intrauterine transmission (NBIT) group and OBI group were significantly lower than that of control group (P<0.001). The level of TLR 9 in DBI group was significantly higher than those in NBIT group and OBI group (P=0.000). (2) The TLR 9 level in HBeAg-negative group was significantly lower than that in HBeAg-positive parturients in OBI group (P=0.01). (3) With the increased severity of intrauterine transmission of HBV in each HBV DNA load group, the TLR 9 level in maternal peripheral blood increased significantly (P<0.05). (4) With the increased severity of intrauterine transmission of HBV, the levels of TLR 9 increased significantly in antiviral therapy, immunoglobulin injection and non-hepatitis B vaccine groups (P<0.05). (5) The expression of TLR 9 in placenta tissues with DBI group was significantly higher than that in OBI group and NBIT group (P<0.05). Conclusions: HBV can inhibit the secretion of TLR 9 in parturient to some extent, but HBeAg can stimulate the secretion of TLR 9. However, with the increased severity of intrauterine transmission of HBV, the level of TLR 9 in parturients is increased by intra-group cross-differentiation. Therefore, TLR 9 is not an independent marker for screening and grouping, but it can be used as an reference indicator for the monitoring and management of HBsAg-positive parturients.

Characterization of Intact Proviruses in Blood and Lymph Node from HIV-Infected Individuals Undergoing Analytical Treatment Interruption.

The role of lymphoid tissue as a potential source of HIV-1 rebound following interruption of antiretroviral therapy (ART) is uncertain. To address this issue, we compared the latent viruses obtained from CD4+ T cells in peripheral blood and lymph nodes to viruses emerging during treatment interruption. Latent viruses were characterized by sequencing near-full-length (NFL) proviral DNA and env from viral outgrowth assays (VOAs). Five HIV-1-infected individuals on ART were studied, four of whom participated in a clinical trial of a TLR9 agonist that included an analytical treatment interruption. We found that 98% of intact or replication-competent clonal sequences overlapped between blood and lymph node. In contrast, there was no overlap between 205 latent reservoir and 125 rebound sequences in the four individuals who underwent treatment interruption. However, rebound viruses could be accounted for by recombination. The data suggest that CD4+ T cells carrying latent viruses circulate between blood and lymphoid tissues in individuals on ART and support the idea that recombination may play a role in the emergence of rebound viremia.IMPORTANCE HIV-1 persists as a latent infection in CD4+ T cells that can be found in lymphoid tissues in infected individuals during ART. However, the importance of this tissue reservoir and its contribution to viral rebound upon ART interruption are not clear. In this study, we sought to compare latent HIV-1 from blood and lymph node CD4+ T cells from five HIV-1-infected individuals. Further, we analyzed the contribution of lymph node viruses to viral rebound. We observed that the frequencies of intact proviruses were the same in blood and lymph node. Moreover, expanded clones of T cells bearing identical proviruses were found in blood and lymph node. These latent reservoir sequences did not appear to be the direct origin of rebound virus. Instead, latent proviruses were found to contribute to the rebound compartment by recombination.

Mitochondrial­DNA­associated TLR9 signalling is a potential serological biomarker for non­small cell lung cancer.

Mitochondrial (mt) DNA has been long suggested to contribute to carcinogenesis, and a variety of mutations in mtDNA have been confirmed to be related to various early stages of cancers; these data revealed that the detection of mtDNA in clinical samples may be a promising approach for cancer diagnosis. In the present study, the serum mtDNA in healthy donors and groups of patients with cancer was detected. It was revealed that patients with lung cancer without metastasis had more mtDNA in serum compared to patients with metastasis. Moreover, TLR9­associated signalling was activated in vitro after treatment with a synthetic CpG oligodeoxyribonucleotide (ODN) called ODN­M362. In addition, our data revealed that TLR9 and its adaptor protein, MyD88, were induced by ODN­M362 in a dose­dependent manner. A human cytokine array to evaluate stimulation of cytokine secretion by ODN­M362 was also used. Our findings may identify the role that TLR9 and mtDNA play in lung cancer progression and metastasis.

Impact of ketamine intervention for acute lung injury on RAGE and TLR9.

OBJECTIVE: The purpose of this study was to explore the benefits of ketamine intervention for acute lung injury (ALI) and its effects on the receptor for advanced glycation end-product (RAGE) and toll-like receptor 9 (TLR9). MATERIALS AND METHODS: Lipopolysaccharide (LPS, 3 mg/kg) was used to induce ALI rat model. Forty healthy Sprague-Dawley rats (6-8 weeks) were assigned into control, model, low ketamine (5 mg/kg), and high ketamine (50 mg/kg) groups. After 24 h, these rats were sacrificed and lungs were collected. RESULTS: The pathological score, lung W/D ratio, the percentage of leukocytes and epithelial in bronchoalveolar lavage fluids (BALF), the expression levels of RAGE, TLR9, and other inflammation markers in serum and lungs were significantly higher in the Model group, indicating a good ALI model. Ketamine intervention restored all these parameters, with more benefits in the High dose group. CONCLUSIONS: The high dose ketamine decreased the degree of ALI by inhibiting the expression of RAGE, TLR9, TNF-α, NF-κB, IL-6 and MPO in tissues.

Higher levels of free plasma mitochondrial DNA are associated with the onset of chronic GvHD.

Toll-like receptor-9 (TLR9) responsive B cells have previously been associated with the onset of extensive chronic graft-versus-host disease (cGvHD). We hypothesized that the onset of cGvHD associated with a higher level of plasma-free mitochondrial DNA (mtDNA), a putative TLR9 agonist. Plasma cell-free mtDNA levels were measured in 39 adult patients post-HSCT with and without cGvHD. mtDNA was isolated from plasma and quantified by Q-PCR amplification. We correlated B cell responsiveness to CpG-DNA, a prototypical TLR9 agonist, and previously identified cGVHD biomarkers with mtDNA levels. Free plasma mtDNA were elevated in patients post-HSCT without cGvHD compared to normal non-HSCT adults. There was a significantly higher level of free plasma mtDNA associated with the onset of cGvHD (3080 ± 1586 versus 1834 ± 1435 copies/µL; p = 0.02) compared to 6 months post-HSCT controls. Free mtDNA levels post-HSCT correlated with B cell responsiveness to CpG-DNA and known cGvHD biomarkers: CXCL10 (p = 0.003), ICAM-1 (p = 0.007), CXCL9 (p = 0.03), sCD25 (p = 0.05) and sBAFF (p = 0.05), and percentage of CD21low B cells. Plasma levels of free mtDNA are increased in cGvHD and may represent an endogenous inflammatory stimulus for TLR9 expressing B cells.

Red Blood Cells Homeostatically Bind Mitochondrial DNA through TLR9 to Maintain Quiescence and to Prevent Lung Injury.

RATIONALE: Potentially hazardous CpG-containing cell-free mitochondrial DNA (cf-mtDNA) is routinely released into the circulation and is associated with morbidity and mortality in critically ill patients. How the body avoids inappropriate innate immune activation by cf-mtDNA remains unknown. Because red blood cells (RBCs) modulate innate immune responses by scavenging chemokines, we hypothesized that RBCs may attenuate CpG-induced lung inflammation through direct scavenging of CpG-containing DNA. OBJECTIVES: To determine the mechanisms of CpG-DNA binding to RBCs and the effects of RBC-mediated DNA scavenging on lung inflammation. METHODS: mtDNA on murine RBCs was measured under basal conditions and after systemic inflammation. mtDNA content on human RBCs from healthy control subjects and trauma patients was measured. Toll-like receptor 9 (TLR9) expression on RBCs and TLR9-dependent binding of CpG-DNA to RBCs were determined. A murine model of RBC transfusion after CpG-DNA-induced lung injury was used to investigate the role of RBC-mediated DNA scavenging in mitigating lung injury in vivo. MEASUREMENTS AND MAIN RESULTS: Under basal conditions, RBCs bind CpG-DNA. The plasma-to-RBC mtDNA ratio is low in naive mice and in healthy volunteers but increases after systemic inflammation, demonstrating that the majority of cf-mtDNA is RBC-bound under homeostatic conditions and that the unbound fraction increases during inflammation. RBCs express TLR9 and bind CpG-DNA through TLR9. Loss of TLR9-dependent RBC-mediated CpG-DNA scavenging increased lung injury in vivo. CONCLUSIONS: RBCs homeostatically bind mtDNA, and RBC-mediated DNA scavenging is essential in mitigating lung injury after CpG-DNA. Our data suggest a role for RBCs in regulating lung inflammation during disease states where cf-mtDNA is elevated, such as sepsis and trauma.

cfDNA correlates with endothelial damage after cardiac surgery with prolonged cardiopulmonary bypass and amplifies NETosis in an intracellular TLR9-independent manner.

Cardiopulmonary bypass (CPB) provokes inflammation culminating in organ dysfunction and increased mortality. Recently, neutrophil extracellular traps (NETs) have been found to be involved in a variety of cardiovascular diseases promoting tissue and organ injury. Here, we aimed to elaborate the proinflammatory potential of circulating cell-free (cf)DNA in patients undergoing cardiac surgery with CPB. Plasma was collected pre- and postoperatively as well as at d1, d3, d5 and d8 after surgery. At d1, we found circulating cfDNA levels to be significantly increased in patients with prolonged CPB duration (>100 min) when compared to those with shorter CPB times (CPB < 100 min). Increased CPB duration yielded in higher levels of circulating mitochondrial (mt)DNA, soluble thrombomodulin (sCD141) and ICAM-1, reflecting endothelial damage. Positive correlation between cfDNA and sCD141 was demonstrated at all time points. Plasma and cfDNA from patients with CPB > 100 min induced NETs release by neutrophils from healthy donors which was not suppressed by inhibitors of intracellular toll-like receptor (TLR)9. DNA binding to neutrophils' surface (s)TLR9 has been evidenced. Altogether, we demonstrate that elevated plasma cfDNA might be useful to assess CPB-mediated detrimental effects, including endothelial damage, in cardiac surgical patients with prolonged CPB duration. cfDNA-triggered NETosis is independent of classical TLR9 signaling.

TLR9 gene polymorphism -1486T/C (rs187084) is associated with uterine cervical neoplasm in Mexican female population.

PURPOSE: The aim of this work was to evaluate the association of single nucleotide polymorphisms in TLR9 (-1486 T/C [rs187084], -1237T/C [rs5743836] and G2848A [rs352140]) with HPV infection, squamous intraepithelial lesions, and uterine cervical neoplasm in a Mexican population. Additionally, the peripheral expression of TLR9 was evaluated to evaluate the differences in the TLR9 expression associated with every genotype in the locus -1486 of the TLR9 gene. The serum concentration of TLR9 was evaluated in a randomly selected subsample. METHODS: Genotyping was performed using predesigned 5' endonuc lease assays and the association of the polymorphisms with the diagnosis groups were assessed by performing multinomial regression models. The relative expression of TLR9 in peripheral blood mononuclear cells was evaluated by real-time polymerase chain reaction and the association of the level of TLR9 expression with the diagnosis was evaluated by performing multinomial regression models. The serum concentration of TLR9 was evaluated in a subsample of patients diagnosed with uterine cervical neoplasm by ELISA. RESULTS: The results showed that genotype TT in the -1486 locus of TLR9 was significantly associated with HPV infection (OR = 3.25, 95% CI 1.12-9.46), squamous intraepithelial cervical lesion (OR = 3.76, 95% CI 1.36-10.41), and uterine cervical neoplasm (OR = 5.30, 95% CI 1.81-15.55). Moreover, the highest level of TLR9 expression was significantly associated with a greater risk for developing squamous intraepithelial cervical lesion and uterine cervical neoplasm. The serum TLR9 concentration was higher in patients with uterine cervical cancer than in controls. CONCLUSION: Our findings indicate that genotype TT in the -1486 locus of the TLR9 gene could comprise a risk genotype for HPV infection, squamous intraepithelial cervical lesion, and uterine cervical neoplasm in Mexican female population. Further studies with larger samples are needed to evaluate if the peripheral expression of TLR9 could be used as a biomarker of uterine cervical neoplasm progression.

Rapid Complexation of Aptamers by Their Specific Antidotes.

Nucleic acid ligands, aptamers, harbor the unique characteristics of small molecules and antibodies. The specificity and high affinity of aptamers enable their binding to different targets, such as small molecules, proteins, or cells. Chemical modifications of aptamers allow increased bioavailability. A further great benefit of aptamers is the antidote (AD)-mediated controllability of their effect. In this study, the AD-mediated complexation and neutralization of the thrombin binding aptamer NU172 and Toll-like receptor 9 (TLR9) binding R10-60 aptamer were determined. Thereby, the required time for the generation of aptamer/AD-complexes was analyzed at 37 °C in human serum using gel electrophoresis. Afterwards, the blocking of aptamers' effects was analyzed by determining the activated clotting time (ACT) in the case of the NU172 aptamer, or the expression of immune activation related genes IFN-1ß, IL-6, CXCL-10, and IL-1ß in the case of the R10-60 aptamer. Gel electrophoresis analyses demonstrated the rapid complexation of the NU172 and R10-60 aptamers by complementary AD binding after just 2 min of incubation in human serum. A rapid neutralization of anticoagulant activity of NU172 was also demonstrated in fresh human whole blood 5 min after addition of AD. Furthermore, the TLR9-mediated activation of PMDC05 cells was interrupted after the addition of the R10-60 AD. Using these two different aptamers, the rapid antagonizability of the aptamers was demonstrated in different environments; whole blood containing numerous proteins, cells, and different small molecules, serum, or cell culture media. Thus, nucleic acid ADs are promising molecules, which offer several possibilities for different in vivo applications, such as antagonizing aptamer-based drugs, immobilization, or delivery of oligonucleotides to defined locations.

Excessive activation of the TLR9/TGF-ß1/PDGF-B pathway in the peripheral blood of patients with systemic lupus erythematosus.

BACKGROUND: Our aim is to study the existence of the TLR9/TGF-ß1/PDGF-B pathway in healthy humans and patients with systemic lupus erythematosus (SLE), and to explore its possible involvement in the pathogenesis of lupus nephritis (LN). METHODS: Protein levels of the cytokines were detected by ELISA. mRNA levels of the cytokines were analyzed by real-time PCR. MTT assay was used to test the proliferation of mesangial cells under different treatments. RESULTS: Compared to healthy controls (N Control = 56), levels of Toll-like receptor (TLR)9, transforming growth factor (TGF)-ß1, and platelet-derived growth factor B (PDGF-B) were increased significantly in the peripheral blood of SLE patients (N SLE = 112). Significant correlations between the levels of TLR9, TGF-ß1, and PDGF-B were observed in both healthy controls and SLE patients. The levels of TGF-ß1 and PDGF-B were greatly enhanced by TLR9 activation in primary cell cultures. The proliferation of mesangial cells induced by the plasma of SLE patients was significantly higher than that induced by healthy controls; PDGF-B was involved in this process. The protein levels of PDGF-B homodimer correlated with the levels of urine protein in SLE patients with LN (N LN =38). CONCLUSIONS: The TLR9/TGF-ß1/PDGF-B pathway exists in humans and can be excessively activated in SLE patients. High levels of PDGF-B may result in overproliferation of mesangial cells in the kidney that are involved in the development of glomerulonephritis and LN. Further studies are necessary to identify TLR9, TGF-ß1, and PDGF-B as new therapeutic targets to prevent the development of glomerulonephritis and LN.

Evaluation of PBMC Distribution and TLR9 Expression in Patients with Systemic Lupus Erythematosus.

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease which results in damage to various organs. Some animal studies have revealed that activation of Toll-like receptors (TLRs) is important in the pathogenesis of SLE. In the present study, the percentage of different immune cell subsets in 35 SLE patients and 38 control subjects was analyzed by flow cytometry. We also assessed the expression of TLR9 in the population of peripheral blood mononuclear cells (PBMCs) including T lymphocytes (CD4+ and CD8+), B lymphocytes (CD19+), NK cells (CD56+) and monocytes (CD14+) in SLE patients and healthy controls. The results showed that the percentage of CD8+ T lymphocytes and CD14+ monocytes were significantly higher (p˂0.001) in the SLE patients than the healthy control subjects. Moreover, the percentage of CD56+ NK cells were significantly lower in the SLE patients than the healthy control subjects (p=0.001). The findings indicated that the expression of TLR9 was significantly higher in CD4+ and CD8+ T lymphocytes and CD19+ B lymphocytes of SLE patients than in control subjects (all p˂0.05). The difference in TLR9 expression are involved in pathogenesis of the SLE, hence it can be used as an indicator for SLE diagnosis.

Low expression of Toll-like receptors in peripheral blood mononuclear cells of pediatric patients with acute lymphoblastic leukemia.

Cancer is the second most common cause of death among children aged 1-14 years. Leukemia accounts for one-third of all childhood cancers, 78% of which is acute lymphoblastic leukemia (ALL). The development of cancer has been associated with malignant cells that express low levels of immunogenic molecules, which facilitates their escape from the antineoplastic immune response. It is thought that it may be possible to rescue the antineoplastic immune response through the activation of recognition receptors, such as Toll-like receptors (TLRs), which activate the innate immune system. TLRs are type I membrane glycoproteins expressed mainly in immune system cells such as monocytes, neutrophils, macrophages, dendritic cells, T, B and natural killer cells. The aim of the present study was to evaluate the expression of TLR1, TLR3, TLR4, TLR7 and TLR9 in peripheral blood mononuclear cells (PBMCs) in patients with ALL and prior to any treatment. PBMCs were obtained from 50 pediatric patients diagnosed with ALL and from 20 children attending the ophthalmology and orthopedics services. The mean fluorescence intensity was obtained by analysis of immunofluorescence. We found lower expression levels of TLR1, TLR3, TLR4, TLR7 and TLR9 in PBMCs from patients with ALL compared with those from control patients. We also observed that the PBMCs from patients with Pre-B and B ALL had lower TLR4 expression than controls and patients with Pro-B, Pre-B, B and T ALL had lower TLR7 expression than controls. The present study is the first to demonstrate reduced expression of TLRs in PBMCs from pediatric patients with ALL. This finding is of great relevance and may partly explain the reduction in the antineoplastic immune response in patients with ALL.

[TLR9 expression is positively correlated with the levels of CD38, HLA-DR and CD95 on peripheral blood mononuclear cells in chronic HBV infected patients].

OBJECTIVE: To explore the relationship between the expression of TLR9 and the levels of CD38, HLA-DR and CD95 on peripheral blood mononuclear cells (PBMCs) of chronic hepatitis B virus (HBV) infected patients. METHODS: 70 chronic HBV infected patients and 12 healthy donors were enrolled in this study, and density gradient centrifugation was used to isolate PBMCs from peripheral blood with EDTA for anticoagulation. Flow cytometry was used to detect the levels of TLR9, CD38, HLA-DR and CD95 on PBMCs. RESULTS: Compared to the healthy donors, chronic HBV infected patients with low viral load or high viral load had significantly higher levels of TLR9, HLA-DR and CD95 on PMBCs. Furthermore, the co-expression rates of TLR9 and CD38, HLA-DR, CD95 on PBMCs were obviously higher than those of the healthy donors. Correlation analysis showed that the expression of TLR9 was positively correlated with CD38 (r=0.345), HLA-DR (r=0.334), CD95 (r=0.227) on PBMCs in the patients with chronic HBV infection. CONCLUSION: The expression of TLR9 increased and was positively associated with CD38, HLA-DR and CD95 on PBMCs during chronic HBV infection.

Expression of Toll­like receptors 3 and 9 in Egyptian systemic lupus erythematosus patients.

BACKGROUND: Systemic lupus erythematosus (SLE) is a common complex disease characterized by chronic generalized inflammation which may involve several tissues and organs. OBJECTIVE: The aim of this work was to study the expression of Toll-like receptors (TLR) 3 and 9 in SLE patients, and to investigate their relationship to clinical features, disease activity, and damage. PATIENTS AND METHODS: The current study included 24 Egyptian female SLE patients and 15 matched controls. Disease activity was assessed using the SLE Disease Activity Index (SLEDAI) and damage using the Systemic Lupus International Collaborating Clinics (SLICC) index. Expression of TLR3 and TLR9 in B- (CD19-positive) and T-lymphocytes (CD3-positive) was studied using flow cytometry. RESULTS: Patient age ranged between 17 and 42 years (mean 26.17 ± 5.78 years). There was a significant difference between patients and controls regarding TLR3/CD3, TLR3/CD19, TLR9/CD3, and TLR9/CD19 expression (p < 0.0001). There were significant correlations of TLR3/CD3, TLR3/CD19, and TLR9/CD19 with serum creatinine (r = 0.52, p = 0.009; r = 0.504, p = 0.012; and r = 0.58, p = 0.003; respectively) and negative correlations with ALT levels (r = -0.42, p = 0.04; r = -0.49, p = 0.016; and r = -0.472, p = 0.02; respectively). CONCLUSION: The results of the study suggest that TLR3 and TLR9 play a role in the pathogenesis of SLE, and have an impact on organ involvement in this disease. More studies concerning the biology and function of TLRs are required in larger patient cohorts, and may lead to development of a new class of drugs.

Endosomal Toll-Like Receptor Status in Patients with Metabolic Syndrome.

BACKGROUND: Metabolic syndrome (MetS) predisposes to both diabetes and cardiovascular disease, and inflammation is pivotal in MetS. The Toll-like receptors (TLRs), TLR2 and TLR4, are implicated in both diabetes and atherosclerosis, are increased in MetS, and contribute to the inflammatory burden. Recent studies also suggest an evolving role of endosomal TLRs in diabetic complications. However, there is a paucity of data with regard to the expression of endosomal TLRs such as TLR3, 7-9 in MetS. AIM: Thus, in this short report, we examine expression of monocytes TLR3 and TLR9 in our cohort of subjects with nascent MetS compared to matched controls. SUBJECTS AND METHODS: Monocytes were isolated from subjects with MetS (n = 45) and matched controls (n = 37), respectively, and TLR3 and TLR9 expression was assessed by intracellular flow cytometry and correlated with nuclear factor (NF)-κB expression. RESULTS: We demonstrate increased endosomal TLR9 expression in MetS compared to controls that correlate with increased nuclear NF-κB expression in the monocytes of these subjects, with no change in TLR3 protein. CONCLUSION: Future studies are required to confirm these findings and determine the role of TLR9 in the increased cardiovascular risk in MetS.