Our goal was to identify genetic risk factors for cutaneous leishmaniasis (CL) caused by Leishmania braziliensis.
Genotyping 2066 CL cases and 2046 controls using Illumina HumanCoreExomeBeadChips ...provided data for 4 498 586 imputed single-nucleotide variants (SNVs). A genome-wide association study (GWAS) using linear mixed models took account of genetic diversity/ethnicity/admixture. Post-GWAS positional, expression quantitative trait locus (eQTL) and chromatin interaction mapping was performed in Functional Mapping and Annotation (FUMA). Transcriptional data were compared between lesions and normal skin, and cytokines measured using flow cytometry and Bioplex assay.
Positional mapping identified 32 genomic loci associated with CL, none achieving genome-wide significance (P < 5 × 10-8). Lead SNVs at 23 loci occurred at protein coding or noncoding RNA genes, 15 with eQTLs for functionally relevant cells/tissues and/or showing differential expression in lesions. Of these, the 6 most plausible genetic risk loci were SERPINB10 (Pimputed_1000G = 2.67 × 10-6), CRLF3 (Pimputed_1000G = 5.12 × 10-6), STX7 (Pimputed_1000G = 6.06 × 10-6), KRT80 (Pimputed_1000G = 6.58 × 10-6), LAMP3 (Pimputed_1000G = 6.54 × 10-6), and IFNG-AS1 (Pimputed_1000G = 1.32 × 10-5). LAMP3 (Padjusted = 9.25 × 10-12; +6-fold), STX7 (Padjusted = 7.62 × 10-3; +1.3-fold), and CRLF3 (Padjusted = 9.19 × 10-9; +1.97-fold) were expressed more highly in CL biopsies compared to normal skin; KRT80 (Padjusted = 3.07 × 10-8; -3-fold) was lower. Multiple cis-eQTLs across SERPINB10 mapped to chromatin interaction regions of transcriptional/enhancer activity in neutrophils, monocytes, B cells, and hematopoietic stem cells. Those at IFNG-AS1 mapped to transcriptional/enhancer regions in T, natural killer, and B cells. The percentage of peripheral blood CD3+ T cells making antigen-specific interferon-γ differed significantly by IFNG-AS1 genotype.
This first GWAS for CL identified multiple genetic risk loci including a novel lead to understanding CL pathogenesis through regulation of interferon-γ by IFNG antisense RNA 1.
A role of IL‐10 is down‐regulating T‐cell responses to schistosome antigens. Since SmATPDases can be correlated to modulation of the immune response, we evaluated the expression of enzymes in S. ...mansoni eggs. Faecal samples were collected from 40 infected individuals to detect coding regions of the SmATPDases. The cytokines were measured in supernatants of PBMC. The analysis was performed by the global median determination and set up high producers (HP) of cytokines. Six individuals expressed SmATPDase1, six expressed SmATPDase2 and six expressed both enzymes. The group who expressed only SmATPDase1 showed a high frequency of IFN‐γ, TNF IL‐4 HP; individuals who expressed only SmATPDase2 showed a high frequency of IFN‐γ, IL‐6 and IL‐4 HP; and individuals who expressed both enzymes showed a high frequency of IL‐10 HP. The comparison of the IFN‐γ/IL‐10 ratio presented higher indices in the group who had SmATPDase 2 expression than those who had the expression of both enzymes. The positive correlation between infection intensity and IL‐10 levels remained only in the positive SmATPDase group. The IL‐10 is the only cytokine induced by the expression of both enzymes. Our data suggest that the expression of both enzymes seems to be a factor that modulates the host immune response by inducing high IL‐10 production.
Chagas disease is a neglected parasitic disease caused by
. While most patients are asymptomatic, around 30% develop Chronic Chagasic Cardiomyopathy (CCC).
Here, we employed high-dimensional flow ...cytometry to analyze CD4
T and B cell compartments in patients during the chronic phase of Chagas disease, presenting the asymptomatic and mild or moderate/severe cardiac clinical forms.
Effector CD27
CD4
T cells were expanded in both CCC groups, and only mild CCC patients showed higher frequencies of effector memory and T follicular helper (Tfh) cells than healthy donors (CTL) and asymptomatic patients. Unsupervised analysis confirmed these findings and further revealed the expansion of a specific subpopulation composed of Tfh, transitional, and central memory CD4
T cells bearing a phenotype associated with strong activation, differentiation, and exhaustion in patients with mild but not moderate/severe CCC. In contrast, patients with mild and moderate/severe CCC had lower frequencies of CD4
T cells expressing lower levels of activation markers, suggesting resting status, than CTL. Regarding the B cell compartment, no alterations were found in naïve CD21
, memory cells expressing IgM or IgD, marginal zone, and plasma cells in patients with Chagas disease. However, expansion of class-switched activated and atypical memory B cells was observed in all clinical forms, and more substantially in mild CCC patients.
Taken together, our results showed that
infection triggers changes in CD4
T and B cell compartments that are more pronounced in the mild CCC clinical form, suggesting an orchestrated cellular communication during Chagas disease.
Overall, these findings reinforce the heterogeneity and complexity of the immune response in patients with chronic Chagas disease and may provide new insights into disease pathology and potential markers to guide clinical decisions.
Immunosenescence is a phenomenon caused by changes in the immune system, and part of these changes involves an increase in circulating immunological biomarkers, a process known as “Inflammaging.” ...Inflammaging can be associated with many diseases related to older people. As the older population continues to grow, understanding changes in the immune system becomes essential. While prior studies assessing these alterations have been conducted in countries with Caucasian populations, this investigation marks a pioneering effort. The object of the study is to describe for the first time that the distribution of cytokines, chemokines, and growth factors serum levels, assessed by Luminex platform, has been examined in a Brazilian population-based study of older adult females and males by age. Blood samples from 2111 participants (≥50 years old) were analyzed at the baseline (2015/2016) of the ELSI-Brazil study. The exploratory variables considered in the study were age, sex, educational level, residence area, geographic region, alcohol and smoking consumption, physical activity, and self-reported medical diagnoses of hypertension, diabetes, asthma, arthritis, and cancer. The association between serum biomarker levels and age was assessed by a quantile regression model adjusted in the total population and stratified by sex. The significance level considered in the analysis was 0.05. The mean age of the participants was 62.9 years, with a slight majority of female (52.7 %). Differences were found between the sexes in the median circulating levels of the CCL11, CXCL10, and FGF biomarkers. Eight biomarkers showed significant associations with age, including the pro-inflammatory CXCL10, TNF-α, IL-6, IL-17, and IL-2; and type 2/regulatory CCL11 and IL-4, showing positive associations, and anti-inflammatory IL-1Ra showing a negative association. The results suggest similar associations between the sexes, revealing an inflammatory profile characterized by types 1 and 2. Remarkably, these findings reinforce the concept of the Inflammaging process in Brazilian population. These findings add novel insights to about the immunosenescence aspects in middle-income countries and help define biomarkers capable of monitoring inflammation in older adults.
•CXCL10, CCL11, TNF-α, IL-6, IL17, IL-4, IL-2, and IL-1Ra are associate with aging.•Older Brazilians exhibit a mixed type 1 and 2 inflammatory immunological profile.•There is a connection between older Brazilian adults and Inflammaging.•Quantile regression robustly assesses serological biomarker concentrations.
Plasmodium vivax causes approximately 100 million clinical malaria cases yearly
. The basis of protective immunity is poorly understood and thought to be mediated by antibodies
. Cytotoxic CD8
T ...cells protect against other intracellular parasites by detecting parasite peptides presented by human leukocyte antigen class I on host cells. Cytotoxic CD8
T cells kill parasite-infected mammalian cells and intracellular parasites by releasing their cytotoxic granules
. Perforin delivers the antimicrobial peptide granulysin and death-inducing granzymes into the host cell, and granulysin then delivers granzymes into the parasite. Cytotoxic CD8
T cells were thought to have no role against Plasmodium spp. blood stages because red blood cells generally do not express human leukocyte antigen class I
. However, P. vivax infects reticulocytes that retain the protein translation machinery. Here we show that P. vivax-infected reticulocytes express human leukocyte antigen class I. Infected patient circulating CD8
T cells highly express cytotoxic proteins and recognize and form immunological synapses with P. vivax-infected reticulocytes in a human leukocyte antigen-dependent manner, releasing their cytotoxic granules to kill both host cell and intracellular parasite, preventing reinvasion. P. vivax-infected reticulocytes and parasite killing is perforin independent, but depends on granulysin, which generally efficiently forms pores only in microbial membranes
. We find that P. vivax depletes cholesterol from the P. vivax-infected reticulocyte cell membrane, rendering it granulysin-susceptible. This unexpected T cell defense might be mobilized to improve P. vivax vaccine efficacy.
Toxoplasmosis is highly endemic worldwide. In Brazil, depending on the geographical region and socioeconomic status, 40–70% of individuals become seropositive at some point in their lives. A ...significant proportion of Toxoplasma gondii‐chronically infected individuals who are otherwise immunocompetent develop recurrent ocular lesions. The inflammatory/immune mechanisms involved in development of ocular lesion are still unknown and, despite previous investigation, there are no reliable immune biomarkers to predict/follow disease outcome. To better understand the impact of the immune response on parasite control and immunopathology of ocular toxoplasmosis, and to provide insights on putative biomarkers for disease monitoring, we assessed the production of a large panel of circulating immune mediators in a longitudinal study of patients with postnatally acquired toxoplasmosis stratified by the presence of ocular involvement, both at the early acute stage and 6 months later during chronic infection, correlating them with presence of ocular involvement. We found that T. gondii‐infected patients, especially during the acute stage of the disease, display high levels of chemokines, cytokines, and growth factors involved in the activation, proliferation, and migration of inflammatory cells to injured tissues. In particular, major increases were found in the IFN‐induced chemokines CXCL9 and CXCL10 in T. gondii‐infected patients regardless of disease stage or clinical manifestations. Moreover, a specific subgroup of circulating cytokines and chemokines including GM‐CSF, CCL25, CCL11, CXCL12, CXCL13, and CCL2 was identified as potential biomarkers that accurately distinguish different stages of infection and predict the occurrence of ocular toxoplasmosis. In addition to serving as predictors of disease development, these host inflammatory molecules may offer promise as candidate targets for therapeutic intervention.
Graphical
Circulating molecules distinguish with a good accuracy different stages of infection and development of ocular lesions in individuals with toxoplasmosis.
Sepsis remains one of the main causes of death in intensive care unit (ICU) worldwide, despite all technological and scientific advances. Microvesicles (MV) have become promising biomarkers for quick ...and accurate monitoring of several illnesses. The aim of this pilot study was to characterize and evaluate the performance of MV as biomarker of clinical outcome in septic and trauma patients. For this purpose, 39 subjects, both genders, aging from 18 to 85 years were included in three groups referred as Sepsis, Trauma and Healthy Control. Kinetic analysis of MV was carried out at four consecutive time points: admission (baseline)/T1, 24 h/T2, 72 h/T3 and outcome/T4 of discharge or death. At admission, an overall increase in total MV (Annexin V+) was observed in Sepsis.MV CD14+ (monocytes) was a putative biomarker to identify trauma patients, while MV CD3+ (T-cells) and CD41+ (platelets) were qualified to discriminated Trauma from Sepsis. Sepsis (Death) presented an increase in MV Annexin V+, CD45+, CD16+, CD14+, and CD41+ in comparison to Sepsis (Discharge). Moreover, Trauma (Death) presented an increase of MV CD3+ and CD235+ as compared to Trauma (Discharge). Analysing the ROC curve of specific MV evaluated according to performance, an accuracy of 100% was found to segregate the outcome in sepsis, and 95% in trauma. Our findings suggest that MV might be useful as a potential role in discriminating outcome in patients with sepsis/septic shock and trauma with high accuracy. However, further studies with a larger number of participants will be necessary to validate our findings.
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•Biomarker identification can be useful in clinical and evolutionary management of septic patients.•The kinetics of microvesicles (MV) may represent a group of biomarkers capable of assessing the profile of septic patients.•MV can be accurate biomarkers to accurately monitor sepsis and trauma clinical outcome.•Total MV, neutrophils and monocytes derived MV are useful parameters to discriminate clinical outcome in sepsis.
Brucella abortus S19 and RB51 strains have been successfully used to control bovine brucellosis worldwide; however, currently, most of our understanding of the protective immune response induced by ...vaccination comes from studies in mice. The aim of this study was to characterize and compare the immune responses induced in cattle prime-immunized with B. abortus S19 or RB51 and revaccinated with RB51. Female calves, aged 4 to 8 months, were vaccinated with either vaccine S19 (0.6-1.2 x 1011 CFU) or RB51 (1.3 x 1010 CFU) on day 0, and revaccinated with RB51 (1.3 x 1010 CFU) on day 365 of the experiment. Characterization of the immune response was performed using serum and peripheral blood mononuclear cells. Blood samples were collected on days 0, 28, 210, 365, 393 and 575 post-immunization. Results showed that S19 and RB51 vaccination induced an immune response characterized by proliferation of CD4+ and CD8+ T-cells; IFN-ɣ and IL-17A production by CD4+ T-cells; cytotoxic CD8+ T-cells; IL-6 secretion; CD4+ and CD8+ memory cells; antibodies of IgG1 class; and expression of the phenotypes of activation in T-cells. However, the immune response stimulated by S19 compared to RB51 showed higher persistency of IFN-ɣ and CD4+ memory cells, induction of CD21+ memory cells and higher secretion of IL-6. After RB51 revaccination, the immune response was chiefly characterized by increase in IFN-ɣ expression, proliferation of antigen-specific CD4+ and CD8+ T-cells, cytotoxic CD8+ T-cells and decrease of IL-6 production in both groups. Nevertheless, a different polarization of the immune response, CD4+- or CD8+-dominant, was observed after the booster with RB51 for S19 and RB51 prime-vaccinated animals, respectively. Our results indicate that after prime vaccination both vaccine strains induce a strong and complex Th1 immune response, although after RB51 revaccination the differences between immune profiles induced by prime-vaccination become accentuated.
•Severe COVID-19 increases the risk for AKI, and consequently the risk for death.•COVID-19 associated AKI leads to higher and sustained levels of immune mediators.•These alterations occur ...independently of death in AKI patients.•CCL-2 and CXCL-10 show a good predictive value regarding AKI development.•In AKI patients, immune mediators are correlated with SARS-CoV-2 viral load.
Severe cases of coronavirus disease 2019 (COVID-19) have increased risk for acute kidney injury (AKI). The exacerbation of the immune response seems to contribute to AKI development, but the immunopathological process is not completely understood.
To analyze levels of circulant immune mediators in COVID-19 patients evolving with or without AKI. We have also investigated possible associations of these mediators with viral load and clinical outcomes.
This is a longitudinal study performed with hospitalized patients with moderate to severe COVID-19. Serum levels of 27 immune mediators were measured by a multiplex immunoassay. Data were analyzed at two timepoints during the follow-up: within the first 13 days of the disease onset (early sample) and from the 14th day to death or hospital discharge (follow-up sample).
We studied 82 COVID-19 patients (59.5 ± 17.5 years, 54.9% male). Of these, 34 (41.5%) developed AKI. These patients presented higher SARS-CoV-2 viral load (P = 0.03), higher frequency of diabetes (P = 0.01) and death (P = 0.0004). Overall, AKI patients presented significantly higher and sustained levels (P < 0.05) of CCL-2, CCL-3, CCL-4, CXCL-8, CXCL-10, IFN-γ, IL-2, IL-6, TNF-α, IL-1Ra, IL-10 and VEGF. Importantly, higher levels of CCL-2, CXCL-10, IL-2, TNF-α, IL-10, FGFb, and VEGF were observed in AKI patients independently of death. ROC curves demonstrated that early alterations in CCL-2, CXCL-8, CXCL-10, IFN-γ, IL-6, IL-1Ra and IL-10 show a good predictive value regarding AKI development. Lastly, immune mediators were significantly associated with each other and with SARS-CoV-2 viral load in AKI patients.
COVID-19 associated AKI is accompanied by substantial alterations in circulant levels of immune mediators, which could significantly contribute to the establishment of kidney injury.
In order to effectively control and monitor schistosomiasis, new diagnostic methods are essential. Taking advantage of computational approaches provided by immunoinformatics and considering the ...availability of Schistosoma mansoni predicted proteome information, candidate antigens of schistosomiasis were selected and used in immunodiagnosis tests based on Enzime-linked Immunosorbent Assay (ELISA). The computational selection strategy was based on signal peptide prediction; low similarity to human proteins; B- and T-cell epitope prediction; location and expression in different parasite life stages within definitive host. Results of the above-mentioned analysis were parsed to extract meaningful biological information and loaded into a relational database developed to integrate them. In the end, seven proteins were selected and one B-cell linear epitope from each one of them was selected using B-cell epitope score and the presence of intrinsically disordered regions (IDRs). These predicted epitopes generated synthetic peptides that were used in ELISA assays to validate the rational strategy of in silico selection. ELISA was performed using sera from residents of areas of low endemicity for S. mansoni infection and also from healthy donors (HD), not living in an endemic area for schistosomiasis. Discrimination of negative (NEG) and positive (INF) individuals from endemic areas was performed using parasitological and molecular methods. All infected individuals were treated with praziquantel, and serum samples were obtained from them 30 and 180 days post-treatment (30DPT and 180DPT). Results revealed higher IgG levels in INF group than in HD and NEG groups when peptides 1, 3, 4, 5 and 7 were used. Moreover, using peptide 5, ELISA achieved the best performance, since it could discriminate between individuals living in an endemic area that were actively infected from those that were not (NEG, 30DPT, 180DPT groups). Our experimental results also indicate that the computational prediction approach developed is feasible for identifying promising candidates for the diagnosis of schistosomiasis and other diseases.
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