Ethnopharmacological relevance: Lonicerae japonicae flos (LJF, the dried flower bud or newly bloomed flower of Lonicera japonica Thunb.), a typical herbal medicine, targets the lung, heart and stomach meridian with the function of clearing heat and detoxication. It ameliorated inflammatory responses and protected against acute lung inflammation in animal models. Acute lung injury (ALI) is a kind of inflammatory disease in which alveolar cells are damaged. However, a network pharmacology study to thoroughly investigate the mechanisms preventing ALI has not been performed.

Aim of the study: In this study, we examined the main active ingredients in LJF and the protective effects of LJF on LPS-induced ALI in rats.

Materials and methods: First, the main active ingredients of LJF were screened in the TCMSP database, and the ALI-associated targets were collected from the GeneCards database. Then, we used compound-target and target-pathway networks to uncover the preventive mechanisms of LJF. Furthermore, we assessed the preventive effects of LJF in an LPS-induced rat model with the RNA-Seq technique to validate the possible molecular mechanisms of the effects of LJF in the treatment of ALI.

Results: The network pharmacology results identified 28 main active compounds in LJF, and eight chemical components highly related to the potential targets, which were potential active compounds in LJF. In all, 94 potential targets were recognized, including IL6, TNF, PTGS2, APP, F2, and GRM5. The pathways revealed that the possible targets of LJF involved in the regulation of the IL-17 signalling pathway. Then, in vivo experiments indicated that LJF decreased the levels of proinflammatory cytokines (TNF-, IL-1, and IL-6) in serum and bronchoalveolar lavage fluid, decreased the levels of oxidative stress factors (MDA and MPO) and increased the activities of SOD and GSH-Px in lung tissue. The RNA-Seq results revealed that 7811, 775 and 3654 differentially expressed genes (DEGs) in Ctrl (control group), ALI-LJF (Lonicerae japonicae flos group) and ALI-DXSM (dexamethasone group), respectively. KEGG pathway analysis showed that the DEGs associated with immune response and inflammation signalling pathways and the IL-17 signalling pathway were significantly enriched in LJF. Compared with those in ALI, the expression of CXCL2, CXCL1, CXCL6, NFKBIA, IFNG, IL6, IL17A, IL17F, IL17C, MMP9 and TNFAIP3, which are involved in the IL-17 signalling pathway, were significantly decreased in the LJF group according to the qRT-PCR analyses.

Conclusions: In view of the network pharmacology and RNA-Seq results, the study identified the main active ingredient and potential targets of LJF involved in protecting against ALI, which suggests directions for further research on LJF.

Keywords: Acute lung injury; IL-17 signalling pathway; Lonicerae japonicae flos; Network pharmacology; RNA-Seq.

Breach of tolerance to gluten leads to the chronic small intestinal enteropathy celiac disease. A key event in celiac disease development is gluten-dependent infiltration of activated cytotoxic intraepithelial lymphocytes (IELs), which cytolyze epithelial cells causing crypt hyperplasia and villous atrophy. The mechanisms leading to gluten-dependent small intestinal IEL infiltration and activation remain elusive. We have demonstrated that under homeostatic conditions in mice, gluten drives the differentiation of anti-inflammatory T cells producing large amounts of the immunosuppressive cytokine interleukin-10 (IL-10). Here we addressed whether this dominant IL-10 axis prevents gluten-dependent infiltration of activated cytotoxic IEL and subsequent small intestinal enteropathy. We demonstrate that IL-10 regulation prevents gluten-induced cytotoxic inflammatory IEL infiltration. In particular, IL-10 suppresses gluten-induced accumulation of a specialized population of cytotoxic CD4⁺CD8αα⁺ IEL (CD4⁺ CTL) expressing Tbx21, Ifng, and Il21, and a disparate non-cytolytic CD4⁺CD8α^- IEL population expressing Il17a, Il21, and Il10. Concomitantly, IL-10 suppresses gluten-dependent small intestinal epithelial hyperproliferation and upregulation of stress-induced molecules on epithelial cells. Remarkably, frequencies of granzyme B⁺CD4⁺CD8α⁺ IEL are increased in pediatric celiac disease patient biopsies. These findings demonstrate that IL-10 is pivotal to prevent gluten-induced small intestinal inflammation and epithelial damage, and imply that CD4⁺ CTL are potential new players into these processes.

Background: Information is limited from real-life studies evaluating the efficacy and safety of brodalumab.

Research design and methods: In this real-life study, we retrospectively examined a database of 90 patients with moderate-to-severe psoriasis treated with brodalumab (210 mg, s.c.) and followed for 1 year. Disease severity and treatment response were assessed by the Psoriasis Area and Severity Index (PASI) at baseline and after 4, 12, 24, 36, and 48 weeks. Predictors of a PASI response were evaluated by logistic regression.

Results: After 48 weeks, 92.2% of patients (mean age 50.2±15 years) treated with brodalumab achieved a PASI score of <3. Furthermore, PASI score decreased from 17.4±10.3 at baseline to 1.7±3.9 and 1.4±3.7 at 12 and 24 weeks, and PASI 75, 90, and 100 response was achieved in 87.3%, 81.8%, and 72.7% of patients respectively at 48 weeks.Univariate regression analysis revealed that previous exposure to anti-IL17A treatment was associated with poorer PASI response between 36-48 weeks. In a range of specific difficult-to-treat cases previously having failed with other biologics, brodalumab significantly improved outcome, leading to complete remission.

Conclusion: Brodalumab was observed to be effective and safe in patients with moderate-severe chronic psoriasis in a real world-setting.

Keywords: PASI; anti-IL17A; brodalumab; erythroderma; plaque psoriasis; psoriasis; pustular; real-life.

IL-17A and IL-22 derived from Th17 cells play a significant role in mucosal immunity and inflammation. TGF-β and IL-6 promote Th17 differentiation; however, these cytokines have multiple targets. The identification and screening of additional molecules that regulate IL-17A and IL-22 responses in certain inflammatory conditions is of great clinical significance. In this study, we show that CDDO-Im, a specific Nrf2 activator, promotes IL-17A and IL-22 responses in murine Th17 cells. In contrast, CDDO-Im inhibits IL-17A response in multiple sclerosis patient-derived PBMCs. However, Nrf2 specifically regulates IL-22 response in vivo. Nrf2 acts through the regulation of antioxidant response element (ARE) binding motifs in target genes to induce or repress transcription. Promoter analysis revealed that Il17a, Rorc, and Ahr genes have several ARE motifs. We showed that Nrf2 bound to ARE repressor (ARE-R2) of Rorc and inhibited Rorc-dependent IL-17A transactivation. The luciferase reporter assay data showed that CDDO-Im regulated Ahr promoter activity. Chromatin immunoprecipitation quantitative PCR data showed that Nrf2 bound to ARE of AhR. Finally, we confirmed that the CDDO-Im-mediated induction of IL-22 production in CD4⁺ T cells was abrogated in CD4-specific Ahr knockout mice (Ahr^CD4 ). CH-223191, a specific AhR antagonist, inhibits CDDO-Im-induced IL-22 production in CD4⁺ T cells, which further confirmed the AhR-dependent regulation. Collectively, our data showed that Nrf2 via AhR pathways regulated IL-22 response in CD4⁺ T cells.

miRNAs regulate gene expression post-transcriptionally in various processes, e.g., immunity, development, and diseases. Since their experimental analysis is complex, in silico target prediction is important for directing investigations. TnP is a candidate peptide for anti-inflammatory therapy, first discovered in the venom of Thalassophryne nattereri, which led to miRNAs overexpression in LPS-inflamed zebrafish post-treatment. This work aimed to predict miR-21, miR-122, miR-731, and miR-26 targets using overlapped results of DIANA microT-CDS and TargetScanFish software. This study described 513 miRNAs targets using highly specific thresholds. Using Gene Ontology over-representation analysis, we identified their main roles in regulating gene expression, neurogenesis, DNA-binding, transcription regulation, immune system process, and inflammatory response. miRNAs act in post-transcriptional regulation, but we revealed that their targets are strongly related to expression regulation at the transcriptional level, e.g., transcription factors proteins. A few predicted genes participated concomitantly in many biological processes and molecular functions, such as foxo3a, rbpjb, rxrbb, tyrobp, hes6, zic5, smad1, e2f7, and npas4a. Others were particularly involved in innate immunity regulation: il17a/f2, pik3r3b, and nlrc6. Together, these findings not only provide new insights into the miRNAs mode of action but also raise hope for TnP therapy and may direct future experimental investigations.

Keywords: TnP; bioinformatics; epigenetic; inflammation; miRNAs; ontology; preclinical toxicological studies.

We studied the genetic epidemiology of primary large-joint (hip and knee) osteoarthritis (OA), in order to find disease risk factors by a candidate-gene approach. We used case-control study in the Croatian Caucasian population. We genotyped 500 OA patients (260 hip, 240 knee; both with total joint replacements) and 597 healthy individuals for single-nucleotide polymorphisms (SNPs) in interleukin 17A (IL17A) (rs2275913) and IL17F (rs763780 and rs1889570) genes. On the basis of our population and allelic and genotypic frequencies haplotypes were predicted by PHASE software and compared between patients and controls. The three-SNP haplotype (rs2275913-rs763780-rs1889570) G-C-A confers predisposition to hip (p < 0.005) but not knee OA. The three-SNP haplotype having opposed nucleotides A-T-G was found significantly associated with 2.6 times higher risk for developing knee (p < 0.02) but not hip OA. The haplotype G-T (IL17A-IL17F; rs2275913-rs763780) is associated with protection to the disease in hip OA (p < 0.01). Our analyses show that two disparate haplotypes within the IL17A-F gene locus are associated with higher risk to developing hip and knee OA in the Croatian population. The data might suggest a difference in the etiology of hip OA from that of the knee OA, perhaps due to an unknown dissimilarity in vulnerability of these joints to the actions of IL17. Alternatively, other differences in genetic factors like the long non-protein coding region LINCMD1 and/or microRNA species like miR133b and miR206 found in the vicinity of the IL17 locus might be involved in the observed risk. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:1972-1978, 2019.

Systemic lupus erythematosus (SLE) is a multifactorial autoimmune disease and polymorphisms in the cytokine genes and their receptors are thought to influence its development. The aim of this case-control study was to investigate the association of the IL-17A rs2275913, IL-17RC rs708567 and TGFB1 rs1800469 polymorphisms with SLE, its clinical manifestations and the polymorphisms influence on the IL-17A serum levels. Altogether 59 SLE patients with lupus nephritis and 95 healthy controls were genotyped by TaqMan assay. Serum levels were determined by Human IL-17A Platinum ELISA kit. From the studied polymorphisms, only TGFB1 T allele was found to be associated with SLE. Within the patient group, IL-17A GG genotype and TGFB1 -509T allele showed an association with the neurological disease and IL-17RC CC genotype appeared to be associated with lupus arthritis. The IL17A serum levels in the SLE and control groups (7.24 pg/ml and 5.76 pg/ml, respectively) did not show any statistical difference. A weak correlation between IL17A levels and SLEDAI-2K was observed. Our results indicate that IL-17A rs2275913, IL-17RCrs708567 and TGFB1 rs1800469 polymorphisms might play a role in the susceptibility and the clinical manifestations of SLE and IL-17A serum levels should be monitored in the course of the disease. The identification of subsets of SLE with an IL-17-driven disease could improve the therapeutic approach leading to more precise personalized treatment.

Keywords: Interleukin-17; Lupus nephritis; Receptors; Single nucleotide polymorphism; Systemic lupus erythematosus; Transforming growth factor beta1.

Glioblastoma multiforme is a highly malignant, heterogenic, and drug resistant tumor. The blood-brain barrier (BBB), systemic cytotoxicity, and limited specificity are the main obstacles in designing brain tumor drugs. In this study a computational approach was used to design brain tumor drugs that could downregulate VEGF and IL17A in glioblastoma multiforme type four. Computational screening tools were used to evaluate potential candidates for antiangiogenic activity, target binding, BBB permeability, and ADME physicochemical properties. Additionally, in vitro cytotoxicity, migration, invasion, tube formation, apoptosis, ROS and ELISA assays were conducted for molecule 6 that was deemed most likely to succeed. The efflux ratio of membrane permeability and calculated docking scores of permeability to glycoproteins (P-gps) were used to determine the BBB permeability of the molecules. The results showed BBB permeation for molecule 6, with the predicted efficiency of 0.55kcal/mol and binding affinity of -37kj/mol corresponding to an experimental efflux ratio of 0.625 and predicted -15kj/mol of binding affinity for P-gps. Molecule 6 significantly affected the angiogenesis pathways by 2-fold downregulation of IL17A and VEGF through inactivation of active sites of HSP90 (predicted binding: -37kj/mol, predicted efficiency: 0.55kcal/mol) and p23 (predicted binding: 12kj/mol, predicted efficiency: 0.17kcal/mol) chaperon proteins. Additionally, molecule 6 activated the 17.38% relative fold of ROS level at 18.3μg/mL and upregulated the caspase which lead the potential synergistic apoptosis through the antiangiogenic activity of molecule 6 and thereby the highly efficacious anticancer upshot. The results indicate that the binding of the molecules to the therapeutic target is not essential to produce a lethal effect on cancer cells of the brain and that antiangiogenic efficiency is much more important.

The role of IL-17A⁺ cells remains controversial among various cancer types. This study aimed to investigate the effects of IL-17A⁺ cells on tumor immune contexture and clinical outcome in muscle-invasive bladder cancer (MIBC). In this study, we enrolled 141 patients from Zhongshan Hospital, 118 patients from Shanghai Cancer Center and 403 patients from TCGA cohort. In vitro studies were conducted in 32 freshly resected tumors. Survival analysis was conducted using Kaplan-Meier and Cox regression analysis. The results suggested that patients with high levels of IL-17A⁺ cells had prolonged overall survival and recurrence-free survival (HR = 0.268, P < .001; and HR = 0.433, P < .001). Moreover, these patients tended to be at lower risk of death and recurrence after adjuvant chemotherapy (P = .012 and P = .004). An increased number of IL-17A⁺ cells correlated with the infiltration of several anti-tumor immune cells into tumors. In addition, IL-17A⁺ cells had an influence on the recruitment, proliferation, and activation of CD8⁺ cells, and were positively associated with the expression of several anti-tumor effector cytokines. In conclusion, tumor-infiltrating IL17A⁺ cells were correlated with an elevated anti-tumor immunity in MIBC. Besides, high infiltration of IL17A⁺ cells can predict benefit from ACT for MIBC patients.

Koala Retrovirus (KoRV) has been widely speculated to cause immune suppression in koalas (Phascolarctos cinereus) and to underlie the koala's susceptibility to infectious disease, however evidence for immunomodulation is limited. The aim of this study is to determine whether immunophenotypic changes are associated with KoRV infection in free ranging Victorian koalas. qPCR was used to examine mRNA expression for Th1 (IFNγ), Th2-promoting (IL6, IL10) and Th17 (IL17A) cytokines, along with CD4 and CD8 in whole blood of koalas (n = 74) from Mt Eccles and Raymond Island in Victoria, Australia, with and without natural chlamydial infection. KoRV positive koalas had significantly lower levels of IL17A (p`0.023) and IFNγ (p = 0.044) gene expression along with a decreased CD4:CD8 gene expression ratio (p = 0.025) compared to negative koalas. No effect of chlamydial infection or combined effect of KoRV and chlamydial infection was detected in these populations. The decreased expression of IFNγ could make KoRV infected koalas more susceptible to persistent chlamydial infection, and a decrease in IL17A could make them more susceptible to gram negative bacterial, fungal and mycobacterial infection; but more tolerant of chlamydial infection.

BACKGROUND

Listeria monocytogenes is a common cause of bacterial meningitis. We developed an animal model of listerial meningitis.

METHODS

In survival studies, C57BL/6 mice received intracisternal injections with different L. monocytogenes sequence type 1 (ST1) colony forming units per milliliter (CFU; n = 48, 105, 106, 107, 108, and 109 CFU/ml). Second, mice were inoculated with 108 CFU/ml ST1 and sacrificed at 6 h and 24 h (n = 12/group). Outcome parameters were clinical score, CFUs, cyto- and chemokine levels, and brain histopathology. Third, 84 mice were inoculated (109 CFU/ml ST1) to determine optimal antibiotic treatment with different doses of amoxicillin and gentamicin. Fourth, mice were inoculated with 109 CFU/ml ST1, treated with amoxicillin, and sacrificed at 16 h and 24 h (n = 12/group) for outcome assessment. Finally, time point experiments were repeated with ST6 (n = 24/group).

RESULTS

Median survival time for inoculation with 108 and 109 CFU/ml ST1 was 46 h and 40 h; lower doses of bacteria led to minimal clinical signs of disease. Brain levels of IL-6, IL-17A, and IFN-γ were elevated at 24 h, and IL-1β, IL-6, IL-10, IFN-γ, and TNF-α were elevated in blood at 6 h and 24 h. Histopathology showed increased meningeal infiltration, vascular inflammation of meningeal vessels, hemorrhages, and ventriculitis. In the treatment model, brain levels of IL-6 and IL-17A and blood levels of IL-6 and IFN-γ were elevated. Compared to ST6, infection with ST1 led initially to higher levels of IL-1β and TNF-α in blood and more profound neuropathological damage. At 16 h post inoculation, IL-1β, IL-10, and TNF-α in blood and IL-6, IL17A, TNF-α, and IFN-γ levels in brain were higher in ST1 compared to ST6 without differences in CFUs between STs. At 24 h, neuropathology score was higher in ST1 compared to ST6 (p = 0.002) infected mice.

CONCLUSIONS

We developed and validated a murine model of listerial meningitis. ST1-infected mice had a more severe inflammatory response and brain damage as compared to ST6-infected mice.

Th17 cells play a key role in immunity against Mycobacterium tuberculosis, our previous research showed that reduced Th17 responses were associated with the severe outcome of Mtb infection. The associations between IL17A polymorphisms and susceptibility of TB has been reported, but the results are inconsistent and the underlying mechanisms is unknown. In this study, we identified a genetic variation (rs8193036) in the promoter region of IL17A is associated with susceptibility to TB. The minor allele T frequency of rs8193036 was significantly different between patients with active TB (29.7%) and healthy controls (32.3%) (OR = 0.81; 95%CI, 0.71-0.93; P = 0.0026). Peripheral blood mononuclear cells from individuals carrying rs8193036CC genotypes produced significantly lower amount of IL17A upon CD3/28 stimulation compared to the individuals carrying rs8193036TT genotypes. Functional assay by reporter luciferase activity and EMSA demonstrated that rs8193036C exhibited significantly lower promotor transcription activities. In conclusion, our study confirmed that IL17A (rs8193036) is a functional SNP that could regulate gene expression though influencing transcription factor binding activity.

BACKGROUND

Despite the fact that antiretroviral therapy (cART) suppresses HIV-viremia, an adequate CD4 T-cell recovery is not always achieved (immunodiscordant response to cART). IL17a-producing CD4 T-cells (Th17) constitutes an important subset involved in the preservation of mucosal surfaces integrity, which depletion has been associated with disease progression in HIV-infection. However, whether Th17 frequency at cART initiation is associated with a poor CD4 T-cell recovery has not been yet explored. Our aim was to explore whether the Th17 cells and other IL17a-producing T-cell subsets at cART initiation were associated with a subsequent immunodiscordant response to cART.

METHODS

We selected pre-cART samples of antiretroviral-naïve subjects with and without a low CD4 recovery after cART (LR-subjects and HR-subjects, respectively). Peripheral blood mononuclear cells (PBMCs) were stimulated with PMA/ionomycine, and the production of several cytokines including IL17a was analyzed by flow cytometry.

RESULTS

A trend to higher Th17 (p = 0.05) and increased frequencies of IL17a-producing Treg (p = 0.011) was found in LR-subjects before cART onset. Despite increased frequencies of both Treg and Th17 in LR-subject at cART initiation, no alteration of Treg/Th17 ratio was observed. While polifunctional profile of CD4 T-cells was not different, frequencies of CD4 T-cells producing cytokine-combinations including IL17a were increased in LR-subjects.

CONCLUSIONS

Increased frequencies of Th17, IL17a-producing Treg and CD4 T-cells producing specific IL17a-containing combinations of cytokines, precede the immunodiscordant response to cART, suggesting a potential contribution of these subsets in such anomalous response to cART.

Homeostasis of subpopulations Th17- and Treg-lymphocytes plays an important role in a holistic and coordinated process of eradication of pathogens and preventing the spread of infection in the body. Study of molecular mechanisms controlling the balance of these cells in the formation of immune deviation in the pathogenesis of infection are particularly relevant. The article presents the results of a study of mRNA expression of transcription factors Th17- and Treg-lymphocytes--RORC2 and FoxP3, respectively, as well as the presence of these cells in peripheral blood in infectious disease (based on an example of infection caused by Mycobacterium tuberculosis). It was established that during the infiltrative (regardless of drug susceptibility testing) and disseminated drug-susceptible pulmonary tuberculosis accompanied by Th17-polarized differentiation of T-lymphocytes, as evidenced by the increased number of CD4+CD161+IL17A+ cells in the blood in association with increased mRNA expression of the transcription factor RORC2 in lymphocytes. In disseminated drug-resistant pulmonary tuberculosis T-lymphocyte differentiation is carried out mainly in the direction of immunosuppressive Treg-cells, as evidenced by the increase in their number in the blood in association with elevated levels of mRNA expression of the transcription factor FoxP3 in lymphocytes.

5-lipoxygenase is a key enzyme in the synthesis of leukotrienes from arachidonic acid. The produced leukotrienes are involved in inflammatory diseases including psoriasis, asthma, and atherosclerosis. A suitable 5-lipoxygenase inhibitor might be useful for preventing and improving the symptoms of leukotriene-related inflammatory diseases. Here, we investigate the mechanism underlying the anti-inflammatory effect of a proanthocyanidin found in red-kerneled rice. Red-kerneled rice proanthocyanidin exhibited potent mixed noncompetitive inhibition of 5-lipoxygenase, with an IC₅₀ of 7.0 μM. This compound decreased leukotriene B₄ production in rat basophilic leukemia-2H3 cells. In imiquimod-induced psoriasis-like mouse skin, topical application of the proanthocyanidin suppressed hyperplasia, decreased inflammatory cell infiltration, and down-regulated expression of the psoriasis-associated genes Il17a, Il22, S100a9, and Krt1. Lipid metabolome analysis by electrospray ionization mass spectrometry showed that red-kerneled rice proanthocyanidin treatment of psoriasis-like mouse skin dose-dependently decreased the production of leukotriene B₄ but no other arachidonate metabolites. Red-kerneled rice proanthocyanidin inhibits 5-lipoxygenase, resulting in a decrease in leukotriene B₄ production and psoriasis-like mouse skin inflammation. These results suggest that this proanthocyanidin may be therapeutically effective for treating leukotriene-related diseases.

Multiple injections of bone marrow mesenchymal stem cells (BMMSCs) have been used for treatment of chronic colitis in mice. We aimed to report the therapeutic effects of a single injection of human umbilical cord mesenchymal stem cells (hUCMSCs) on acute and chronic colitis. Male C57BL/6JNarl mice were divided into control, phosphate-buffered saline (PBS), and hUCMSCs treated groups, respectively. Acute and chronic colitis were induced in the mice (except controls) using 3% dextran sulfate sodium (DSS). The mice in the hUCMSCs group underwent a single injection of hUCMSCs. The disease activity index (DAI), colon length, histology, colon inflammation score, in vivo stem cells images, and blood cytokine levels were recorded. The DAI was significantly higher in the hUCMSCs group than in the control group and lower than in the PBS group on all days. The colon length was significantly longer and the colon inflammation score was significantly lower in the hUCMSCs group than in the PBS group on days 8 and 25. IL17A, Gro-α, MIP-1α, MIP-2, and eotaxin were significantly lower in the hUCMSCs group than in the PBS group on days 8 and 25. Single-injection hUCMSCs improved DSS-induced acute colitis and decreased progression of acute colitis to chronic colitis.

Genetic factors and the immunologic response have been suggested to determine the susceptibility against the infection and the outcome of Chagas disease. In the present study, we analysed three IL17A genetic variants (rs4711998, rs8193036 and rs2275913) regarding the predisposition to Trypanosoma cruzi infection and the development of chronic Chagas cardiomyopathy (CCC) in different Latin American populations. A total of 2,967 individuals from Colombia, Argentina, Bolivia and Brazil, were included in this study. The individuals were classified as seronegative and seropositive for T. cruzi antigens, and this last group were divided into asymptomatic and CCC. For T. cruzi infection susceptibility, the IL17A rs2275913*A showed a significant association in a fixed-effect meta-analysis after a Bonferroni correction (P = 0.016, OR = 1.21, 95%CI = 1.06-1.41). No evidence of association was detected when comparing CCC vs. asymptomatic patients. However, when CCC were compared with seronegative individuals, it showed a nominal association in the meta-analysis (P = 0.040, OR = 1.20, 95%CI = 1.01-1.45). For the IL17A rs4711998 and rs8193036, no association was observed. In conclusion, our results suggest that IL17A rs2275913 plays an important role in the susceptibility to T. cruzi infection and could also be implicated in the development of chronic cardiomyopathy in the studied Latin American population.

OBJECTIVE

Mucosal gene expression have not been fully enlightened in inflammatory bowel disease (IBD). Aim of this study was to define IL23A, IL17A, IL17F and TLR9 expression in different IBD phenotypes.

METHODS

Evaluation of mRNA levels was performed in paired non-inflamed and inflamed mucosal biopsies of newly diagnosed 50 Crohn's disease (CD) and 54 ulcerative colitis (UC) patients by quantitative real-time PCR analysis.

RESULTS

IL17A and IL17F expression levels were significantly increased in inflamed IBD mucosa. Inflamed CD ileal and UC mucosa showed increased IL23A, while only inflamed CD ileal samples showed increased TLR9 mRNA level. Correlation between analysed mRNAs levels and endoscopic and clinical disease activity were found in UC, but only with clinical activity in CD.

CONCLUSIONS

Both CD and UC presented expression of Th17-associated genes. Nevertheless, expression profiles between different disease forms varies which should be taken into account for future research and therapeutics strategies.

In this study, were genotyped 22 single nucleotide polymorphisms (SNPs) in 13 genes that encode the pro-inflammatory (IL-1α, IL-1β, IL-1R, IL-4Rα, IL-12, IFN-γ, TNF-α, and IL-2) and anti-inflammatory (IL-1RA, TGF-β, IL-4, IL-6 and IL-10) cytokines of 350 individuals by PCR-SSP (polymerase chain reaction - sequence specific primer). A total of 473 individuals were genotyped for IL17A and IL17F genes by PCR-RFLP (restriction fragment length polymorphism). The sample consisted of healthy and unrelated subjects from a mixed population from Parana state, in the South region of Brazil. The frequency analyses and genotype data are available in the Supplementary materials and are accessible at Allele Frequency Net Database (AFND).

Dendritic cells (DCs) represent essential antigen-presenting cells that are critical for linking innate and adaptive immunity, and influencing T-cell responses. Among pattern recognition receptors, DCs express C-type lectin receptors triggered by both exogenous and endogenous ligands, therefore dictating pathogen response, and also shaping T-cell immunity. We previously described in rat, the expression of the orphan C-type lectin-like receptor-1 (CLEC-1) by DCs and demonstrated in vitro its inhibitory role in downstream T helper 17 (Th17) activation. In this study, we examined the expression and functionality of CLEC-1 in human DCs, and show a cell-surface expression on the CD16- subpopulation of blood DCs and on monocyte-derived DCs (moDCs). CLEC-1 expression on moDCs is downregulated by inflammatory stimuli and enhanced by transforming growth factor β. Moreover, we demonstrate that CLEC-1 is a functional receptor on human moDCs and that although not modulating the spleen tyrosine kinase-dependent canonical nuclear factor-κB pathway, represses subsequent Th17 responses. Interestingly, a decreased expression of CLEC1A in human lung transplants is predictive of the development of chronic rejection and is associated with a higher level of interleukin 17A (IL17A). Importantly, using CLEC-1-deficient rats, we showed that disruption of CLEC-1 signaling led to an enhanced Il12p40 subunit expression in DCs, and to an exacerbation of downstream in vitro and in vivo CD4+ Th1 and Th17 responses. Collectively, our results establish a role for CLEC-1 as an inhibitory receptor in DCs able to dampen activation and downstream effector Th responses. As a cell-surface receptor, CLEC-1 may represent a useful therapeutic target for modulating T-cell immune responses in a clinical setting.

Oxidized low-density lipoprotein receptor 1 (OLR1) and interleukin 17A (IL17A) have pro-inflammatory roles in the development of cardiovascular disorders. The present study evaluated the association of OLR1 and IL17A and their polymorphisms with the development of femoropopliteal (FP) artery disease. The mRNA expression of OLR1 and IL17A in peripheral blood mononuclear cells as well as the frequency of OLR1 rs11053646 and IL17A rs8193037 and rs3819025 polymorphisms were assessed by polymerase chain reaction in 70 patients with FP artery disease and 80 age-matched disease-free controls. Furthermore, the levels of plasma cytokines were assessed by multiplex immunoassay. OLR1 and IL17A mRNA expression was significantly higher in patients with FP artery disease compared with that in controls (P<0.001). No significant difference was observed in the genotypic frequencies of OLR1 rs11053646 (P=0.87) or in IL17A rs8193037 and rs3819025 (P=0.80 and 0.92, respectively) polymorphisms between patients with FP artery disease and controls. Plasma IL4, -6, -10, -22, -31 and -33 as well as soluble cluster of differentiation 40 ligand and tumor necrosis factor-α levels were significantly increased among FP artery disease patients compared with controls (P<0.05). Furthermore, OLR1 expression was positively correlated with triglyceride (r=0.463, P<0.001), low-density lipoprotein cholesterol (r=0.507, P<0.001) and total cholesterol levels (r=0.357, P=0.006) in patients with FP artery disease. To the best of our knowledge, the present study was the first to identify an association between OLR1 and IL17A genes and FP artery disease. OLR1 and IL17A mRNA transcripts may be associated with blood lipid parameters and with the development of FP artery disease.

Influenza A virus (IAV) is the most common infectious agent in humans, and infects approximately 10-20% of the world's population, resulting in 3-5 million hospitalizations per year. A scientific literature search was performed using the PubMed database and the Medical Subject Headings (MeSH) "Influenza A H1N1" and "Genetic susceptibility". Due to the amount of information and evidence about genetic susceptibility generated from the studies carried out in the last influenza A H1N1 pandemic, studies published between January 2009 to May 2020 were considered; 119 papers were found. Several pathways are involved in the host defense against IAV infection (innate immune response, pro-inflammatory cytokines, chemokines, complement activation, and HLA molecules participating in viral antigen presentation). On the other hand, single nucleotide polymorphisms (SNPs) are a type of variation involving the change of a single base pair that can mean that encoded proteins do not carry out their functions properly, allowing higher viral replication and abnormal host response to infection, such as a cytokine storm. Some of the most studied SNPs associated with IAV infection genetic susceptibility are located in the FCGR2A, C1QBP, CD55, and RPAIN genes, affecting host immune responses through abnormal complement activation. Also, SNPs in IFITM3 (which participates in endosomes and lysosomes fusion) represent some of the most critical polymorphisms associated with IAV infection, suggesting an ineffective virus clearance. Regarding inflammatory response genes, single nucleotide variants in IL1B, TNF, LTA IL17A, IL8, IL6, IRAK2, PIK3CG, and HLA complex are associated with altered phenotype in pro-inflammatory molecules, participating in IAV infection and the severest form of the disease.

Keywords: cytokine storm; genetic susceptibility; inflammation; influenza; polymorphisms.

The association of increased levels of tumour-infiltrating gamma-delta (γδ) T cells with favorable prognosis across many cancer types and their ability to recognize stress antigens in an MHC unrestricted manner has led to an increased interest in exploiting them for cancer immunotherapy. We performed single-cell RNA sequencing (scRNA-seq) of peripheral blood γδ T cells from healthy adult donors and from fresh tumour biopsies of breast cancer patients. We identified five γδ T cells subtypes in blood and three subtypes of γδ T cells in breast tumour. These subtypes differed in the expression of genes contributing to effector functions such as antigen presentation, cytotoxicity, and IL17A and IFNγ production. Compared with the blood γδ T cells, the breast tumour-infiltrating γδ T cells were more activated, expressed higher levels of cytotoxic genes, yet were immunosuppressed. One subtype in the breast tumour that was IFNγ-positive had no obvious similarity to any of the subtypes observed in the blood γδ T cell and was the only subtype associated with improved overall survival of breast cancer patients. Taken together, our study has identified markers of subtypes of human blood γδ T cells and uncovered a tumour-infiltrating γδ T cells subtype associated improved overall cancer survival.