TLR4 Gene Research Articles

LPS- and LTA-Induced Expression of TLR4, MyD88, and TNF-α in Lymph Nodes of the Akkaraman and Romanov Lambs.

Toll-like receptor (TLR)-mediated inflammatory processes play a critical role in the innate immune response during the initial interaction between the infecting microorganism and immune cells. This study aimed to investigate the possible microanatomical and histological differences in mandibular and bronchial lymph nodes in Akkaraman and Romanov lambs induced by lipopolysaccharide (LPS) and lipoteichoic acid (LTA) and study the gene, protein, and immunoexpression levels of TLR4, myeloid differentiation factor 88 (MyD88), and tumor necrosis factor-α (TNF-α) that are involved in the immune system. Microanatomical examinations demonstrated more intense lymphocyte infiltration in the bronchial lymph nodes of Akkaraman lambs in the LPS and LTA groups compared to Romanov lambs. TLR4, MyD88, and TNF-α immunoreactivities were more intense in the experimental groups of both breeds. Expression levels of MyD88 and TNF-α genes in the bronchial lymph node of Akkaraman lambs were found to increase statistically significantly in the LTA group. TLR4 gene expression level in the mandibular lymph node was found to be statistically significantly higher in the LTA + LPS group. In conclusion, dynamic changes in the immune cell populations involved in response to antigens such as LTA and LPS in the lymph nodes of both breeds can be associated with the difference in the expression level of the TLR4/MyD88/TNF-α genes.

Tlr4 gene deletion accelerates retinal degeneration in rd10 and P23H/+ murine models of retinitis pigmentosa

AbstractPurpose: The photoreceptor degeneration associated to retinitis pigmentosa (RP) is caused by a wide variety of genetic mutations, which greatly complicates the development of a universal effective treatment. As a process independent of the causative mutation, the inflammatory response resulting from neuronal death could represent a potential candidate for a general treatment for RP. In this context, we studied the role of TLR4, one of the main mediators of innate immunity, on the retinal degenerative process in two murine models of RP.Methods: rd10 and P23H/+ mice were used to evaluate the consequences of Tlr4 haploinsufficiency and complete deletion on retinal degeneration. Visual function was evaluated by electroretinographic recordings and optomotor test and retinal cytoarchitecture by immunohistology. The myeloid cell population (main mediators of the innate immune response) reactivity was studied by immunohistology and flow cytometry. Gene expression was assessed by RT‐quantitative PCR.Results: We found that Tlr4 expression was significantly increased in the retina of both RP models. To assess the effect of Tlr4 deletion in PR progression first we confirmed that abrogation of Tlr4 expression did not impair visual function in wild‐type animals. However, Tlr4 deficiency accelerated RP progression in both rd10 and P23H/+ mice. Deletion of a single Tlr4 allele reduced the retinal electroretinographic response and photoreceptor survival in both RP models. Moreover, complete abrogation of Tlr4 further exacerbates this phenotype. These results were confirmed by assessing visual acuity by optomotor test in P23H/+ mice. Microglia analysis showed higher proportion of phagocytic microglia and lower of homeostatic microglia in the photoreceptor layers upon Tlr4 total deletion.Conclusions: The TLR4 receptor exerts a neuroprotective effect on the retinal neurodegenerative process in RP, thus suggesting a potential therapeutic target for the disease.

Genome-wide investigation and expression analysis of TLR gene family reveals its immune role in Vibrio tolerance challenge of Manila clam

Toll-like receptors (TLRs) play key roles in activating immune responses during infection. In this study, we identified TLR genes in Manila clam at the genome-wide level and characterized it into 9 types according to the Ruditapes philippinarum genome annotation, including TLR1 (1–10), TLR2 (1–10), TLR2–2 (1–5), TLR3 (1–3), TLR4 (1–9), TLR5, TLR6 (1–5), TLR7 (1–2), and TLR13 (1–4). The length of TLR proteins varied from 128 to 1257 amino acids. The molecular weights and theoretical isoelectric point (pI) values ranged from 14.63 to 143.32 kDa and 4.47 to 9.45, respectively. TLR genes showed universal expression levels in adductor muscle (AM), mantle (M), foot (F), gill (GI), pipe (P), digestive gland (DG), gonad (GO) and labial palp (L). Transcriptome analysis revealed that the expression level of TLR4, TLR5, TLR7 and TLR13 genes are significantly highly expressed in resistant individuals of Manila clam under Vibrio anguillarum challenge, indicating these TLR genes may play significant roles in response to invading pathogens. The results obtained in this work will provide valuable insights into the immune function of TLR gene in R. philippinarum.

Immunomodulatory effect of ethanol-soluble oligopeptides from Atlantic cod (Gadus morhua)

There are many active substances in Atlantic cod (Gadus morhua) explaining the variety of biological activities. In order to study the immunomodulatory activity and the mechanism of Atlantic cod peptides at the cellular level. In this study, cod peptides were isolated by 80 % ethanol extraction method, the isolated ethanol-soluble cod peptides (CP-ES) were investigated and their immunomodulatory activity was verified. Additionally, CP-ES showed lower molecular weight and more hydrophobic amino acids. CP-ES could promote the proliferation of spleen lymphocytes and T lymphocytes in mice, suggesting that CP-ES may regulate adaptive immunity. It promoted the release of NO and the expression of iNOS, TNF-α, IL-6 and IL-1β genes in macrophages, suggesting that CP-ES may regulate innate immunity. CP-ES could promote the expression of TLR2 gene, and the peptides identified in CP-ES were docked with TLR2 to predict the peptides playing a major role in CP-ES. These results suggested that CP-ES may regulate the immune activity of both innate and adaptive lines.

Immune-enhancing effects of Astragalus polysaccharides and Ganoderma lucidum polysaccharides on Vibrio harveyi flgJ DNA vaccine in grouper.

Astragalus polysaccharides (APS) and Ganoderma lucidum polysaccharides (GLP) have been shown to possess strong immunoregulatory properties in aquatic animals. In this study, the fragment containing Vibrio harveyi flgJ gene was ligated into pcDNA3.1(+) vector and pcDNA3.1(+)-flgJ was constructed as DNA vaccine. APS and GLP were used as DNA vaccine adjuvants to evaluate the immunoregulatory effect by intramuscular injection to pearl gentian grouper (♀Epinephelus fuscoguttatus × ♂E. lanceolatus). The results showed that pcDNA3.1(+)-flgJ combined with APS or GLP could significantly up-regulate the innate and adaptive immune response in fish, including serum-specific antibody titres, catalase and lysozyme activities. At the same time, DNA vaccine combined with APS or GLP significantly up-regulated the expression levels of CD8α, IgM, IL-1β, MHC-Iα, MyD88 and TLR3 genes in thymus, head kidney, spleen and liver of pearl gentian grouper in comparison with those of the pFlgJ group. After 42 days post-vaccination, V. harveyi was used to challenge pearl gentian grouper by intraperitoneal injection. The relative percentage of survival (RPS) of pFlgJ, pFlgJ +APS, pFlgJ +GLP and pFlgJ+APS+GLP groups were 69%, 81%, 77% and 88%, respectively. These results suggested APS and GLP were potential adjuvants for DNA vaccine against V. harveyi infection in pearl gentian grouper.

Andrographolide protects against doxorubicin-and arsenic trioxide-induced toxicity in cardiomyocytes.

Andrographolide (AG) is a lactone diterpene with valuable biological activities. This in vitro study evaluated whether AG can protect cardiomyocytes under toxicities triggered with anti-cancer chemotherapeutic agents, doxorubicin (DOX) and arsenic trioxide (ATO). H9C2 cells were pretreated with AG (0.5-10µM) for 24h and then exposed to DOX (1μM) or ATO (35μM) for another 24h period. For determination of cell viability or cytotoxicity, MTT and lactate dehydrogenase (LDH) assay were used. Total oxidant and antioxidant capacities were estimated by determining hydroperoxides and ferric reducing antioxidant power (FRAP) levels. Real time-polymerase chain reaction was also used for quantitative evaluation of TLR4 gene expression. AG inhibited cardiomyocytes proliferation at the concentrations of more than 20μM. However, it considerably enhanced cell viability and decreased cytotoxicity of DOX and ATO at the concentration range of 2.5-10μM in MTT and LDH assays. AG significantly declined hydroperoxides concentration in ATO-treated cardiomyocytes and raised FRAP value in DOX- and ATO-treated cells. Furthermore, AG notably lessened TLR4 expression in H9C2 cells after exposure to DOX- and ATO. In conclusion, these data presented that AG was able to reverse DOX- and ATO-induced cardiotoxicity in vitro. The cardiomyocyte protective activities of AG may be due to the decrease in TLR4 expression and total oxidant capacity and increase in total antioxidant capacity.

BAP1 depletion in human B-lymphoblast cells affects the production of innate immune cytokines and chemokines.

BRCA1 associated protein 1 (BAP1) is a ubiquitin C-terminal hydrolase that deubiquitinates histone H2AK119ub and other proteins and regulates the expression of multiple genes. The knockout of this tumor suppressor gene results in severe thymic atrophy, complete loss of the T cell lineage, and abnormal B cell development in mice. In the current study, we investigated in vitro effects of BAP1 knockout on cytokine and chemokine production using the human B-lymphoblast cell line TSCE5. We confirmed that knockout changed the production of innate immune-associated genes and their receptors. The CCL19, CCR7, CCL2, and CXCR5 genes associated with T and B cell migration were upregulated. Knockout cells producing high levels of CCL19 showed acceleration of actin polymerization, which is essential for cell migration. CD69, PTPRC, and TLR3 genes that activate inflammation were downregulated. The tumor necrosis factor ligand genes TNF, LTA, and TNFSF10 were downregulated by knockout. In knockout cells, TNFα production was strongly downregulated upon the addition of H2 O2 , but NF-κB in the basal condition and when TNFα was added was augmented, suggesting that these cells could respond to TNFα. These results indicated that BAP1 affects the expression of chemokines and cytokines, T and B cell migration, and activated inflammation associating with innate immunity.

Expression pattern and diagnostic value of ferroptosis-related genes in acute myocardial infarction.

Ferroptosis is a form of regulatory cell death (RCD) caused by iron-dependent lipid peroxidation. The role of ferroptosis in the process of acute myocardial infarction (AMI) is still unclear and requires further study. Therefore, it is helpful to identify ferroptosis related genes (FRGs) involved in AMI and explore their expression patterns and molecular mechanisms. The AMI-related microarray datasets GSE66360 and GSE61144 were obtained using the Gene Expression Omnibus (GEO) online database. GO annotation, KEGG pathway enrichment analysis and Protein-protein interaction (PPI) analysis were performed for the common significant differential expression genes (CoDEGs) in these two datasets. The FRGs were obtained from the FerrDb V2 and the differentially expressed FRGs were used to identify potential biomarkers by receiver operating characteristic (ROC) analysis. The expression of these FRGs was verified using external dataset GSE60993 and GSE775. Finally, the expression of these FRGs was further verified in myocardial hypoxia model. A total of 131 CoDEGs were identified and these genes were mainly enriched in the pathways of "inflammatory response," "immune response," "plasma membrane," "receptor activity," "protein homodimerization activity," "calcium ion binding," "Phagosome," "Cytokine-cytokine receptor interaction," and "Toll-like receptor signaling pathway." The top 7 hub genes ITGAM, S100A12, S100A9, TLR2, TLR4, TLR8, and TREM1 were identified from the PPI network. 45 and 14 FRGs were identified in GSE66360 and GSE61144, respectively. FRGs ACSL1, ATG7, CAMKK2, GABARAPL1, KDM6B, LAMP2, PANX2, PGD, PTEN, SAT1, STAT3, TLR4, and ZFP36 were significantly differentially expressed in external dataset GSE60993 with AUC ≥ 0.7. Finally, ALOX5, CAMKK2, KDM6B, LAMP2, PTEN, PTGS2, and ULK1 were identified as biomarkers of AMI based on the time-gradient transcriptome dataset of AMI mice and the cellular hypoxia model. In this study, based on the existing datasets, we identified differentially expressed FRGs in blood samples from patients with AMI and further validated these FRGs in the mouse time-gradient transcriptome dataset of AMI and the cellular hypoxia model. This study explored the expression pattern and molecular mechanism of FRGs in AMI, providing a basis for the accurate diagnosis of AMI and the selection of new therapeutic targets.

<i>TLR9</i> gene expression in immune cells of patients with psoriasis

Background. Psoriasis (skin lesions and psoriatic arthritis PA) is a chronic inflammatory autoimmune disease that can be triggered by excessive activation of endosomal toll-like receptors (TLRs), mainly TLR9. Elevated TLR9 levels are observed in both PA and psoriasis. Therefore, studying the expression pattern of the TLR9 gene may help select therapies for patients with PA and psoriasis.
 Aim. To study the expression pattern of the TLR9 gene in blood mononuclear cells of PA and psoriasis patients without joint involvement for possible use in the transition to targeted therapy.
 Materials and methods. Mononuclear cells were isolated from the peripheral blood of 31 patients with psoriasis vulgaris without joint involvement, 45 patients with PA, and 20 healthy volunteers. TLR9 gene expression was analyzed by real-time polymerase chain reaction.
 Results. A comparison of expression levels in PA patients and healthy volunteers showed that the expression level of TLR9 in PA patients was 591 times higher than that in healthy volunteers. The expression level of TLR9 in psoriasis patients without joint involvement was also significantly (423-fold) higher than that in healthy subjects.
 Conclusion. TLR9 gene expression in mononuclear cells of psoriasis patients with severe skin lesions is similar to that in PA patients. High levels of TLR9 gene expression may be a marker of possible joint involvement in patients with psoriasis and indicate the need to reconsider the therapeutic approach to a particular patient.

Immune and Genomic Analysis of Boxer Dog Breed and Its Relationship with Leishmania infantum Infection.

Leishmaniosis, one of the most important zoonoses in Europe, is caused by Leishmania infantum, an intracellular protozoan parasite. This disease is endemic in the Mediterranean area, where the main reservoir is the dog. Several studies indicate a possible susceptibility to L. infantum infection with clinical signs in some canine breeds. One of them is the boxer breed, which shows a high prevalence of disease. In this study, immunological and genomic characterization of serum samples from boxer dogs living in the Mediterranean area were evaluated to analyze the immune response and the possible genetic explanation for this susceptibility. Serum levels of cytokines IFN-γ, IL-2, IL-6, IL-8, and IL-18 were determined by ELISA commercial tests, while the genotyping study was performed using the CanineHD DNA Analysis BeadChip. The results show relevant differences in the serum levels of cytokines compared to published data on other canine breeds, as well as sequence changes that could explain the high susceptibility of the boxer breed to the disease. Concretely, polymorphic variants in the CIITA, HSF2BP, LTBP1, MITF, NOXA1, PKIB, RAB38, RASEF, TLE1, and TLR4 genes were found, which could explain the susceptibility of this breed to L. infantum infection.

Genome-wide investigation of toll-like receptor genes (TLRs) in Procambarus clarkia and their expression pattern in response to black may disease

As a crucial component of pattern-recognition receptors (PRRs) that recognizing pathogen-associated molecular patterns (PAMPs) and defending against invading pathogens, the Toll-like receptors (TLRs) have been paid extensive attention. While the identification and functional roles of TLRs in innate immunity have been reported in a plenty of organisms, the systematic knowledge of TLRs is still lacking in the red swamp crayfish (Procambarus clarkia). In current study, a total of 7 tlr genes were identified in P. clarkia based on the published transcriptome and genome data. The PcTLRs length varied from 939 to 1517aa and contain typical domains of TLR protein, including transmembrane region, varied LRR and TIR domains. 7 Pctlr genes were distributed in 5 chromosomes and 2 scaffolds. The expression pattern of different Pctlr genes in different tissues (hepatopancreas, gill and muscle) and in response to black may disease (BMD) showed significant difference. In addition, 5 proteins that might interact with PcTLR-2 were predicted, among them the expression pattern of dorsal and relish was consistent with Pctlr-2 in three tissues, while the other genes were not. The PcTLR-2-Dorsal/Relish pathway might play crucial roles in response to BMD infection. The results provided a theoretical foundation for further studies on the molecular mechanisms of TLRs in BMD infection in the red swamp crayfish and provided reference for the research of other crustacean species.

Association of TLR7 and TLR9 genes polymorphisms in Egyptian patients with systemic lupus erythematosus

IntroductionSystemic lupus erythematosus (SLE) is a chronic, inflammatory, multiorgan, systemic autoimmune disease. It is characterized by the high production of autoantibodies against nuclear compounds. TLRs (toll-like receptors 7/9) are pattern-recognition receptors that recognize nucleic acids and induce proinflammatory responses by activating NF-kB and producing type I interferon, which play a role in eliciting innate/adaptive immune responses and developing chronic inflammation. TLR7 and TLR9 single nucleotide polymorphisms (SNPs) have been linked to systemic lupus erythematosus in numerous studies (SLE). In this work, we wanted to evaluate and analyze single nucleotide polymorphisms (SNPs) in the TLR7 (rs3853839) and TLR9 (rs187084) genes among Egyptian SLE patients and healthy controls. MethodWhole blood samples were taken from 100 SLE patients and 100 controls; DNA was extracted and then processed for TLR7 rs3853839 and TLR9 rs187084 single nucleotide polymorphisms analysis by real-time polymerase chain reaction technology and restriction fragment-length polymorphism. We also assessed the association between TLR 7 and TLR 9 genes polymorphism with SLE clinical parameters. ResultsOur results showed that TLR7 rs3853839 CG genotypes and G allele were significantly associated with SLE. Also, TLR7 rs3853839 genotypes and alleles were significantly associated with nephritis, arthritis, oral ulcers, and thrombocytopenia.Whereas genotypes and alleles of TLR9 were not significantly associated with the risk nor the clinical characteristics of SLE except for malar rash. ConclusionIn the investigated Egyptian cohort, our findings suggest that TLR7 rs3853839 gene polymorphisms increase the risk for SLE development and play a role in developing clinical characteristics, especially nephritis.

PSUN112 Expression of Vitamin D Receptor Pathway Genes Across Tissues of Individuals with Obesity

Abstract Introduction Vitamin D deficiency is a substantial comorbidity in 50% of pediatric patients and is linked with poorer health outcomes in children. Vitamin D levels are inversely related to BMI. Therefore, the prevalence of children with low vitamin D levels is increasing as the prevalence of pediatric obesity increases. Pediatric patients with obesity and vitamin D deficiency also have a uniquely increased risk of metabolic syndrome, as compared to their lean peers. However, measured levels of vitamin D correlate with other physiological markers of vitamin D effects in lean individuals but not obese individuals. Since vitamin D levels measured as 25-hydroxyvitmain D (serum 25(OH)D) reflect a storage form of vitamin D, their levels may not be a true reflection of vitamin D action in the body in an obese population. The aim of this study was to provide foundational knowledge to understand if expression of vitamin D receptor (VDR)-target genes in different metabolic pathways correlate with each other in diverse tissues, and thus may be used as a reference standard for vitamin D action in the body. Methods We performed a secondary analysis of samples obtained from 89 obese adolescents aged 12 to 18 years old that were consented under a past IRB-approved protocol. The samples were collected at the time of bariatric surgery between 2004 and 2019. Subject data included age, gender, race/ethnicity, and BMI. Samples collected included blood, intestinal, and subcutaneous adipose tissue. The tissues were analyzed via Real Time-PCR to obtain quantitative levels of VDR-target gene expression, which included TLR4, THBD, and VDR in subcutaneous adipose tissue; and TRPV6, S100G, and VDR in intestinal tissue. Gene expression levels were normalized to the average of two housekeeping genes, GAPDH and RPLPO. Blood samples were analyzed for vitamin D levels. Results VDR-target gene expression of THBD, VDR, and TLR4 in subcutaneous adipose tissue was significantly correlated (p <0.05). In intestinal tissue, we also saw significant correlation between TRPV6, S100G, and VDR (p <0.05). THBD, TLR4, TRPV6, S100G, and VDR gene expression levels from the respective tissues did not correlate with circulating serum 25(OH)D levels (p >0.05). Conclusion These important preliminary findings show VDR-target genes have correlated expression patterns within different tissues – one which stores vitamin D (adipose) and one which doesn't (intestinal). Interestingly, the VDR-target gene expression levels correlated with each other despite the genes being involved in different metabolic pathways in diverse tissues. These findings also show that VDR-target gene expression does not correlate with circulating serum 25(OH)D levels. This discrepancy supports that 25(OH)D levels do not indicate levels of vitamin D action and may not be an appropriate indicator of vitamin D deficiency in the obese population. Thus, VDR-target gene expression levels may provide a better reference standard for vitamin D action in the body. This study may provide the first step in determining a new and more accurate biomarker for vitamin D deficiency and treatment in obesity. Presentation: Sunday, June 12, 2022 12:30 p.m. - 2:30 p.m.

Isoferulic acid affords the antiviral potential and restrains white spot syndrome virus proliferation in crayfish (Procambarus clarkii)

White spot syndrome virus (WSSV), the causative agent of White spot disease (WSD), not only caused huge economic losses, but also greatly limited the development of crustacean breeding industry. Chinese herbs are widely used and have great application potential in antiviral research. In thist study, the antiviral effects of 11 Chinese herb extracts were evaluated in Procambarus clarkii (crayfish) model of WSSV infection, among which Cimicifuga foetida L. extract showed the highest inhibition rate (88.22%) against WSSV replication. On this basis, the anti-WSSV effect of Isoferulic acid (IFA), a major bioactive component of Cimicifuga foetida L., was further investigated. The results showed that IFA significantly inhibited WSSV replication (96.57%, 50 mg/kg) in a dose-dependent manner and significantly improved the survival of WSSV-challenged crayfish. IFA had the potential preventive and therapeutic effect against WSSV infection, and the preventive effect was better than the therapeutic effect. Mechanistically, IFA suppressed the expression of the immediate early gene ie1, the DNA polymerase gene DNApol and envelope protein gene Vp28 to inhibit WSSV replication, activated TLR, CTL and ProPo genes expression to block ie1 transcription, and suppressed BAF, STAT, NF-κb and Crustin 1 genes expression to elevate innate immunity against WSSV infection. Besides, IFA upregulated the cMnSOD, mMnSOD, CAT and GST genes expression, and downregulated the COX-1 and COX-2 genes expression to balance the oxidative stress and inflammatory damage caused by WSSV infection. This study provides a theoretical basis and meaningful reference for the development of IFA as a highly effective and practical anti-WSSV drug.

Synonymous mutations in TLR2 and TLR9 genes decrease COPD susceptibility in the Chinese Han population

IntroductionPrevious studies have found associations between polymorphisms in some candidate genes and chronic obstructive pulmonary disease (COPD) risk. However, the association between TLR2 and TLR9 polymorphisms and COPD risk remains uncertain. MethodsFour variants (rs352140, rs3804099, rs3804100, and rs5743705) of the TLR2 and TLR9 genes in 540 COPD patients and 507 healthy controls were genotyped using the Agena MassARRAY system. Odds ratio (OR) and 95% confidence interval (CI) were calculated to assess the association of TLR2 and TLR9 polymorphisms with COPD risk by logistic regression analysis. ResultsTLR9-rs352140, TLR2-rs3804100, and TLR2-rs5743705 were related to a lower risk of COPD among Chinese people and the significance still existed after Bonferroni correction. Additionally, rs3804099, rs3804100, and rs352140 were found to be associated with COPD development in different subgroups (males, age ≤ 68 years, smokers, BMI < 24 kg/m2, and acute exacerbation). ConclusionsOur findings indicated that TLR9 and TLR2 polymorphisms had protective effects on the development of COPD among Chinese people.

Association of toll-like receptors polymorphisms with COPD risk in Chinese population.

Background: Previous studies have reported that the Toll-like receptors (TLRs) are related with the progress of chronic obstructive pulmonary disease (COPD). We aimed to explore the association of TLRs single nucleotide polymorphisms (SNPs) and COPD risk. Methods: 170 COPD patients and 181 healthy controls were enrolled in this case-control study. MassARRAY platform was used for genotyping seven tagging SNPs (TLR2: rs3804100, rs4696480, rs3804099; TLR3: rs3775290, rs3775291, rs5743305; TLR9: rs352140) of TLRs. The correlations between the SNPs and COPD risk were determined using logistic regression. Results: We found that the rs3775291 of TLR3 significant decreased the risk of COPD (TT versus CC: non-adjusted OR = 0.329, 95% CI = 0.123-0.879, p = 0.027). In the genetic models analysis, the rs3775291 was associated with a decreased effect of COPD based on the recessive model (TT versus CC/CT: non-adjusted OR = 0.377, 95% CI = 0.144-0.988p = 0.047). The rs4696480 of TLR2 gene was associated with a decreased risk of COPD after adjustment by age and gender (TA versus AA: adjusted OR = 0.606, 95% CI = 0.376-0.975, p = 0.039). Conclusion: Our study showed that genetic variants in TLRs were associated with risk of COPD. The rs3775291 and rs4696480 may act as a potential biomarker for predicting the risk of COPD in Chinese population.

Gut microbiota-dependent adaptor molecule recruits DNA methyltransferase to the TLR4 gene in colonic epithelial cells to suppress inflammatory reactions.

The intestine is inhabited by a large number of commensal bacteria that are immunologically non-self, potentially causing inflammation. However, in a healthy intestine, inflammation is strictly controlled at low levels to maintain homeostasis. We previously reported that the gut microbiota induce DNA methylation of the gene encoding Toll-like receptor (TLR) 4, a pattern recognition receptor that recognizes lipopolysaccharides of gram-negative bacteria, in colonic epithelial cells, suggesting its role in controlling intestinal inflammation. However, there remains a question of how gut microbiota cause methylation of only specific genes including TLR4, despite the fact that DNA methyltransferase (DNMT) is common to all genes targeted for methylation. Here, we identified RBM14 as an adaptor molecule that recruits DNMT to the TLR4 gene. RBM14 was shown to bind DNMT3 and be expressed at significantly higher levels in an intestinal epithelial cell (IEC) line with hypermethylated TLR4 gene than in an IEC line with hypomethylated TLR4 gene. In addition, RBM14 interacted with DNA regions of the TLR4 gene, and knockdown of RBM14 suppressed DNA methylation of the TLR4 gene in IECs. Furthermore, RBM14 expression was higher in colonic epithelial cells of conventional mice than in those of germ-free mice. Collectively, these results indicate that the gut microbiota induce methylation of the TLR4 gene in colonic epithelial cells by upregulating RBM14, which can recruit DNMT3 to the gene. The regulation of adaptor molecules such as RBM14, which bind to specific target genes and recruit DNMT, can explain, at least in part, how gut microbiota contribute to the maintenance of intestinal homeostasis through epigenetic control of specific gene expression in IECs.

Entamoeba histolytica HM-1: IMSS gene expression profiling identifies key hub genes, potential biomarkers, and pathways in Amoebiasis infection: a systematic network meta-analysis.

Entamoeba histolytica (E. histolytica) is an anaerobic parasite that causes Amoebiasis in the intestine or extraintestinal, with immunology, genetics, and environmental variables all playing a part in the disease's development, but its molecular mechanism is unknown. One of the primary obstacles in understanding the etiology of Amoebiasis will be identifying the genetics profiling that controls the Amoebiasis network. By examining the gene expression profile of Amoebiasis and comparing it with healthy controls, we could identify differentially expressed genes (DEGs). DEGs were used to build the Amoebiasis protein interaction network and calculated its network topological properties. We discovered nine key hub genes (KHGs): JUN, PTGS2, FCGR3A, MNDA, CYBB, EGR1, CCL2, TLR8, and LRRK2 genes. The genes JUN and EGR1 were transcriptional factors (TFs) and up-regulated, others down-regulated. hsa-miR-155-5p, hsa-miR-101-3p, hsa-miR-124-3p, hsa-miR-26b-5p, and hsa-miR-16-5p are also among the essential miRNAs that have been demonstrated to be targeted by KHGs. These KHGs were primarily enriched in the IL-17 signaling pathway, TNF signaling pathway, NOD-like receptor signaling pathway, and Toll-like receptor signaling pathway. miRNAs were grouped in various pathways, focusing on the TGF-β signaling pathway, human immunodeficiency virus 1 infection, insulin signaling pathway, signaling pathways regulating pluripotency of stem cells, etc. Amoebiasis KHGs (JUN, PTGS2, CCL2, and MNDA) and their associated miRNAs are the primary targets for therapeutic methods and possible biomarkers. Furthermore, we identified drugs for genes JUN, PTGS2, FCGR3A, CCL2, and LRRK2. KHGs, on the other hand, required experimental validation to prove their efficacy.

Cloning of Toll-like Receptor 3 Gene from Schizothorax prenanti (SpTLR3), and Expressions of Seven SpTLRs and SpMyD88 after Lipopolysaccharide Induction.

Toll-like receptor 3 (SpTLR3) from Schizothorax prenanti (S. prenanti) was cloned and identified, and the tissue distribution of the SpTLR3 gene was examined in this study. Moreover, the relative mRNA expression levels of myeloid differentiation factor 88 gene (SpMyD88) and seven TLR genes (SpTLR2, SpTLR3, SpTLR4, SpTLR18, SpTLR22-1, SpTLR22-2 and SpTLR22-3) from S. prenanti after lipopolysaccharide (LPS) challenge were analyzed through quantitative real-time polymerase chain reaction (qRT-PCR). The full length of SpTLR3 gene is 3097 bp, and complete coding sequence (CDS) is 2715 bp, which encodes 904 amino acids. The SpTLR3 amino acid sequence shared 43.94–100% identity with TLR3 sequences from other vertebrates; SpTLR3 was expressed in all eight tissues examined; and the highest level appeared in the liver, which was significantly higher than in all other tissues (p < 0.05), followed by the levels in the heart and muscles. LPS significantly up-regulated all eight genes in the S. prenanti tissues at 12 or 24 h (p < 0.05). Compared with the PBS control group, no significant transcripts changes were found in SpTLR2 or SpTLR3 at 12 h after LPS induction, but they were significantly up-regulated at 24 h (p < 0.001). The most abundant transcripts were found in the head kidney SpTLR22 genes after 24 h LPS induction, with high to low levels, which were SpTLR22-1 (564-fold), SpTLR22-3 (508-fold) and SpTLR22-2 (351-fold). Among these eight genes, the expression level of SpTLR4 was the least up-regulated. Overall, SpTLR4 in the head kidney was involved in the antibacterial immune response earlier, and the level was increased at 12 h with extreme significance after LPS stimulation (p < 0.001), while the other seven genes were the most significantly up-regulated at 24 h post injection. Taken together, the results suggest that SpMyD88, SpTLR2, SpTLR3, SpTLR4, SpTLR18, SpTLR22-1, SpTLR22-2 and SpTLR22-3 participate in an innate immune response stimulated by LPS, and the response intensity of the genes was organ-specific, with differing kinetics. Our findings will contribute to a more complete understanding of the roles of these TLR genes in antibacterial immunity.

Association of TLR2 and TLR9 gene polymorphisms with atopic dermatitis: a systematic review and meta-analysis with trial sequential analysis

Atopic dermatitis (AD) is a chronic, inflammatory skin disease. The mechanism was complex. Genetic mutations of Toll-like receptor (TLR) may be associated with AD, yet still unclear. We aim to provide specific evidence of the association of TLR2, TLR9 gene polymorphisms with AD. Publications were selected according to the criteria. Newcastle-Ottawa Scale was applied to evaluate the quality. The value of ORs and 95%CIs were applied to measure the associations. According to the heterogeneity, the effects model of fixed or random was selected in data combination. For TLR2 gene rs5743708 polymorphism, under allele and recessive contrasts, the pooled data showed a significant correlation, which was A vs a, OR = 0.51 (95%CI: 0.30, 0.86); AA vs Aa + aa, OR = 0.54 (95%CI: 0.33, 0.88). For TLR2 gene rs4696480 polymorphism, under allele, homozygous, heterozygous, and dominant contrasts, the pooled data showed a significant correlation, which was A vs a, OR = 0.79 (95%CI: 0.64, 0.97), AA vs aa, OR = 0.65 (95%CI: 0.43, 0.97), Aa vs aa, OR = 0.68 (95%CI: 0.48, 0.97), AA + Aa vs aa, OR = 0.67 (95%CI: 0.49, 0.93). There are significant associations of TLR2 gene rs5743708, rs4696480 polymorphisms with atopic dermatitis, while no associations are found in TLR9 gene rs5743836, rs187084 polymorphisms.