Genetic variation of FcγRIIa induces higher uptake of Leishmania infantum and modulates cytokine production by adherent mononuclear cells in vitro.

Introduction: Single nucleotide variations (SNVs) are specific genetic variations that commonly occur in a population and often do not manifest phenotypically. However, depending on their location and the type of nucleotide exchanged, an SNV can alter or inhibit the function of the gene in which it occurs. Immunoglobulin G (IgG) receptor genes have exhibited several polymorphisms, including rs1801274, which is found in the FcgRIIa gene. The replacement of A with T results in a Histidine (H) to Arginine (R) substitution, altering the affinity of the IgG receptor for IgG subtypes and C-reactive protein (CRP). In this study, we analyzed rs1801274 and its functional implications concerning L. Infantum uptake and cytokine production. Methods: We genotyped 201 individuals from an endemic area for visceral leishmaniasis to assess the presence of rs1801274 using Taqman probes for a candidate gene study. Additionally, we included seventy individuals from a non-endemic area for a functional study. Subsequently, we isolated and cultivated one-week adherent mononuclear cells (AMCs) derived from the peripheral blood of participants residing in the non-endemic region in the presence of L. infantum promastigotes, with and without antigen-specific IgG and/or CRP. We analyzed the rate of phagocytosis and the production of nitric oxide (NO), tumor necrosis factor (TNF)-a, interleukin (IL)-10, IL-12 p70, IL-1b, IL- 6, and IL-8 in the culture supernatants. Results and discussion: In participants from the endemic region, the A/G (H/R isoform) heterozygous genotype was significantly associated with susceptibility to the disease. Furthermore, SNVs induced a change in the phagocytosis rate in an opsonin-dependent manner. Opsonization with IgG increased the production of IL-10, TNF-a, and IL-6 in AMCs with the H/R isoform, followed by a decrease in NO production. The results presented here suggest that the rs1801274 polymorphism is linked to a higher susceptibility to visceral leishmaniasis.

Progressive multifocal leukoencephalopathy triggered by COVID-19 in a previously asymptomatic person living with undiagnosed HIV infection.

This report presents the case of a 47-year-old male patient who worked as a mathematics teacher and experienced the sudden onset of disorientation, aphasia, and acalculia during an online class. The current study reveals the first documented case of HIV and progressive multifocal leukoencephalopathy with the detection of SARS-CoV-2 and human polyomavirus 2 (previously known as John Cunningham virus) in the cerebrospinal fluid. Furthermore, serum analysis revealed elevated concentrations of interleukin (IL)-6, IL-17, and IL-8, which are potential factors known to reduce the expression of tight junctions and adhesion molecules in the extracellular matrix, thereby affecting the permeability of the blood-brain barrier. Finally, the study discusses whether SARS-CoV-2 triggers or exacerbates progressive multifocal leukoencephalopathy.

Association of gestational diabetes mellitus and negative modulation of the specific humoral and cellular immune response against Toxoplasma gondii.

In order to evaluate and compare the specific immune response of pregnant women (PW) chronically infected with Toxoplasma gondii, with and without gestational diabetes mellitus (GDM), and the humoral response of their respective newborns (NB), the study was carried out on 81 PW (34 GDM and 47 controls) from whose medical records the results of the oral glucose tolerance test (OGTT) were obtained, and blood samples were collected at the third trimester of pregnancy; also, on 45 NBs (20 GDM and 25 controls) from whom umbilical cord blood samples were obtained. Humoral immunity was analyzed by measuring anti-T. gondii total IgG, IgG subclasses and IgG avidity. To evaluate cellular immunity, peripheral blood mononuclear cells (PBMC) from 32 PW (16 GDM and 16 controls) were cultured, supernatant cytokines were determined, and flow cytometry was performed to analyze the expression at lymphocytes of surface molecules, cytokines and transcription factors. All PW and NBs were positive for total IgG, and the prevalent subclass was IgG1. There was a negative correlation between the OGTT glycemia of PW and the levels of total IgG, IgG1 and IgG avidity. The IgG avidity of the GDM group was significantly lower than the control group. Patients from the GDM group had a higher number of T lymphocytes expressing markers of cell activation and exhaustion (CD28 and PD-1). In the presence of T. gondii soluble antigen (STAg) the amount of CD4+ T cells producing IFN-γ, IL-10 and IL-17 was significantly lower in the GDM group, while there was no difference between groups in the number of CD4+ CD25HighFOXP3+LAP+ functional Treg cells. Additionally, under STAg stimulus, the secretion of IL-17, IL-4, TNF and IL-2 cytokines at PBMCs culture supernatant was lower in the GDM group. In conclusion, there was a correlation between the increase in blood glucose and the decrease in levels of anti-T. gondii antibodies, associated with the decreased IgG avidity in patients who develop GDM. Also, the GDM group had decreased immune responses in Th1, Th2 and Th17 profiles, suggesting an association between GDM and the negative modulation of the humoral and cellular immune responses against T. gondii.

In silico designing of a recombinant multi-epitope antigen for leprosy diagnosis.

BACKGROUND: Leprosy is caused by Mycobacterium leprae and Mycobacterium lepromatosis. Most of the affected population lives in low-income countries and may take up to 10 years to show any clinical signs, which is how physicians diagnose it. However, due to progressive cell damage, early diagnosis is very important. The best way to confirm leprosy is through bacilloscopic, which only confirms the diagnosis and has low accuracy or PCR, that requires specialized operators and is expensive. Since the bacteria are fastidious and do not grow in any culture media, therefore, diagnosing leprosy in the lab is still a challenge. In this concern, a recombinant multi-epitope protein can be a beneficial strategy in the management of the diagnosis, as diverse immunogenic epitopes are precisely selected to detect specific antibodies. Therefore, the purposes of the present study were to select immunogenic epitopes from different relevant proteins, with immunogenic properties, and then to construct a recombinant multi-epitope protein that accuses the presence of the antibodies in the early stages of the disease, making it more than appropriate to be applied as a diagnostic tool. RESULTS: We selected 22 common proteins from both species and, using bioinformatics tools, predicted B and T cell epitopes. After multiple filtering and analyzing, we ended up with 29 epitopes {MHC-I (total 18) and MHC-II (total 11)} from 10 proteins, which were then merged into one construct. Its secondary and tertiary structures were also predicted and refined to comprise the amino acid residues in the best conformation possible. The multi-epitope protein construct was stable, non-host homologous, non-allergic, non-toxic, and elicit humoral and cellular responses. It has conformational B cell epitopes and potential to elicit IFN-γ, IL-4, and IL-10 secretion. CONCLUSIONS: This novel recombinant multi-epitope protein constructed using the common epitopes from M. leprae and M. lepromatosis has a huge immunological potential, is stable, and can be lyophilized to be used in ELISA plates or even in biosensors, which are user-friendly diagnosis tools, facilitating translation into human sample tests.

Hemolymph of triatomines presents fungistatic activity against Cryptococcus neoformans and improves macrophage function through MCP-I/TNF-α increase.

Background: Triatomines are blood-feeding arthropods belonging to the subfamily Triatominae (Hemiptera; Reduviidae), capable of producing immunomodulatory and water-soluble molecules in their hemolymph, such as antimicrobial peptides (AMPs). In this work, we evaluated the antifungal and immunomodulatory activity of the hemolymph of Meccus pallidipennis (MPH) and Rhodnius prolixus (RPH) against Cryptococcus neoformans. Methods: We assessed the activity of the hemolymph of both insects on fungal growth by a minimum inhibitory concentration (MIC) assay. Further, RAW 264.7 macrophages were cultivated with hemolymph and challenged with C. neoformans. Then, their phagocytic and killing activities were assessed. The cytokines MCP-1, IFN-γ, TNF-α, IL-10, IL-12, and IL-6 were measured in culture supernatants 4- and 48-hours post-infection. Results: Both hemolymph samples directly affected the growth rate of the fungus in a dose-dependent manner. Either MPH or RPH was capable of inhibiting fungal growth by at least 70%, using the lowest dilution (1:20). Treatment of RAW 264.7 macrophages with hemolymph of both insects was capable of increasing the production of MCP-I and TNF-α. In addition, when these cells were stimulated with hemolymph in the presence of C. neoformans, a 2- and a 4-fold increase in phagocytic rate was observed with MPH and RPH, respectively, when compared to untreated cells. For the macrophage killing activity, MPH decreased in approximately 30% the number of viable yeasts inside the cells compared to untreated control; however, treatment with RPH could not reduce the total number of viable yeasts. MPH was also capable of increasing MHC-II expression on macrophages. Regarding the cytokine production, MCP-I and TNF-α, were increased in the supernatant of macrophages treated with both hemolymphs, 4 and 48 hours after stimulation. Conclusion: These results suggested that hemolymph of triatomines may represent a source of molecules capable of presenting antifungal and immunomodulatory activity in macrophages during fungal infection.

Association of recurrent upper respiratory tract infections with low production of oxygen intermediates in children.

OBJECTIVES: Upper respiratory tract infections in children generally have significant morbidity and mortality. There is little data available about functional immaturity of the immune system and the child's susceptibility to infections at the beginning of their lives, thus, justifying a more specific immunological analysis. METHOD: Analysis of hemograms and innate and adaptive immune responses in 95 children between age 1 to 6 years with episodes of recurrent respiratory infections (test group n = 39) and without these episodes (control group n = 56) was carried out. The production of reactive oxygen intermediates by peripheral blood cells stimulated by phorbol myristate acetate was analyzed. Additionally, the number of B lymphocytes, auxiliary T lymphocytes, and cytotoxic cells was determined using flow cytometry. RESULTS: Results from both groups did not show statistically significant differences in red blood cells, total leukocytes count, and the differential neutrophils, eosinophils, basophils, lymphocytes, and monocytes count. The analysis of the number of B lymphocytes, auxiliary T lymphocytes (LTCD4), and cytotoxic cells (LTCD8) also did not show any difference between both groups. However, the production of radical oxygen intermediates was significantly reduced in the test group as compared to the control group (p < 0.05). CONCLUSIONS: There was no difference in the analysis of hemograms, leukograms, or the number of lymphocytes, LTCD4, LTCD8, or LTCD19. The reduced production of oxygen intermediates in the affected group suggests that these children's microbicide capacity is compromised, which may be related to their recurrent respiratory infections.

Congenital transmission of Mexican strains of Trypanosoma cruzi TcIa: interaction between parasite and human placental explants.

Congenital transmission of Chagas disease plays an important role in endemic countries because it is not a diagnosis that is encountered frequently in prenatal care. Due to limited information regarding congenital transmission of Trypanosoma cruzi in Mexico, the present study aimed to investigate protozoan infectivity and modulation of immune responses in human placental explants infected with T. cruzi Ia Mexican strains. The Inc-5 strain showed increased infectivity and modulated IL-1ß, IL-10 and TLR-4, decreasing their expression after 24 h of infection. Both strains (Inc-5 and Ninoa) stimulated the production of TNF-α and decreased IL-6 levels 96 h after infection. An important detachment of the syncytiotrophoblast caused by infection with T. cruzi was observed after 24 h of infection. In this study, ex vivo infection of human placental villi was performed to better understand interactions involving parasitic T. cruzi and human placental tissue. It was concluded that the strains of TcIa present parasitism in placental tissue, modulation of the innate immune system of the placenta, and cause intense detachment of the syncytiotrophoblast, a fact that may be more associated with abortion and premature birth events than the congenital transmission itself, justifying the low rate of this transmission mechanism by this genotype.

Evaluation of Hormonal Influence in Patients with Fractures Attributed to Osteoporosis.

Objective The present study aims to evaluate the influence of hormonal levels of vitamin D, calcitonin, testosterone, estradiol, and parathyroid in patients with fractures attributed to osteoporosis when compared with young patients with fractures resulting from high-impact accidents. Methods Blood samples were collected from 30 elderly patients with osteoporosis-attributed fractures (T-score ≤ -2.5) (osteoporotic group), and from 30 young patients with fractures resulting from high-impact accidents (control group). Measurement of 1,25-hydroxyvitamin D (Kit Diasorin, Saluggia, Italy), calcitonin (Kit Siemens, Tarrytown, NY, USA), testosterone, estradiol, and parathyroid hormone (Kit Beckman Couter, Indianapolis, IN, United States) was performed using a chemiluminescence technique. Data were inserted into a Microsoft Excel (Microsoft Corp., Armonk, WA, USA) spreadsheet and analyzed using Statview statistical software. Results showing non-normal distribution were analyzed with nonparametric methods. The Mann-Whitney test was applied for group comparison, and a Spearman test correlated hormonal levels. Statistical significance was set at p < 0.05. All analyzes compared gender and subjects with and without osteoporosis. Results Women with osteoporosis had significantly lower levels of estradiol and vitamin D ( p = 0.047 and p = 0.0275, respectively). Men with osteoporosis presented significantly higher levels of parathyroid hormone ( p = 0.0065). There was no significant difference in testosterone and calcitonin levels. Conclusion Osteoporosis patients presented gender-related hormonal differences. Women had significantly lower levels of estradiol and vitamin D, whereas men had significantly higher parathyroid hormone levels, apparently impacting the disease.

Evaluation of Hormonal Influence in Patients with Fractures Attributed to Osteoporosis / Avaliação da influência hormonal em pacientes com fraturas atribuídas a osteoporose

Abstract Objective The present study aims to evaluate the influence of hormonal levels of vitamin D, calcitonin, testosterone, estradiol, and parathyroid in patients with fractures attributed to osteoporosis when compared with young patients with fractures resulting from high-impact accidents. Methods Blood samples were collected from 30 elderly patients with osteoporosisattributed fractures (T-score ≤-2.5) (osteoporotic group), and from 30 young patients with fractures resulting from high-impact accidents (control group). Measurement of 1,25-hydroxyvitamin D (Kit Diasorin, Saluggia, Italy), calcitonin (Kit Siemens, Tarrytown, NY, USA), testosterone, estradiol, and parathyroid hormone (Kit Beckman Couter, Indianapolis, IN, United States) was performed using a chemiluminescence technique. Data were inserted into a Microsoft Excel (Microsoft Corp., Armonk, WA, USA) spreadsheet and analyzed using Statview statistical software. Results showing non-normal distribution were analyzed with nonparametric methods. The Mann-Whitney test was applied for group comparison, and a Spearman test correlated hormonal levels. Statistical significance was set at p < 0.05. All analyzes compared gender and subjects with and without osteoporosis. Results Women with osteoporosis had significantly lower levels of estradiol and vitamin D (p = 0.047 and p = 0.0275, respectively). Men with osteoporosis presented significantly higher levels of parathyroid hormone (p = 0.0065). There was no significant difference in testosterone and calcitonin levels. Conclusion Osteoporosis patients presented gender-related hormonal differences. Women had significantly lower levels of estradiol and vitamin D, whereas men had significantly higher parathyroid hormone levels, apparently impacting the disease.

Resumo Objetivo Avaliar a influência dos níveis hormonais de vitamina D, calcitonina, testosterona, estradiol e paratormônio em pacientes com fratura atribuída a osteoporose, quando comparados com pacientes jovens que tiveram fraturas decorrentes de acidente de alto impacto. Métodos Foram coletadas amostras de sangue de 30 pacientes idosos com fratura atribuída a osteoporose (T-score ≤-2,5) (grupo com osteoporose) e 30 amostras de sangue de pacientes jovens que sofreram fraturas decorrentes de acidentes de alto impacto (grupo controle). Foram realizadas dosagem de 1,25-hidroxivitamina D (Kit Diasorin, Saluggia, Italy), calcitonina (Kit Siemens, Tarrytown, NY, USA), testosterona, estradiol e paratormônio (Kit Beckman Couter, Indianapolis, IN, United States) pela técnica de quimiluminescência. Os dados foram inseridos em uma planilha de dados no programa Microsoft Excel (Microsoft Corp., Redmond, WA, EUA) e analisados pelo programa de estatística Statview. Os resultados que apresentaram distribuição não normal foram analisados com métodos não paramétricos. Para análise de variáveis comparando-se os dois grupos, aplicou-se o teste Mann-Whitney. Foi utilizado o teste de correlação de Spearman para a correlacionar os níveis hormonais. Um valor-p >0.05 foi considerado significante. Todas as análises foram feitas comparando gênero e grupos de pacientes come sem osteoporose. Resultados Mulheres com osteoporose apresentam níveis significativamente menores de estradiol e vitamina D (p = 0.047 e p = 0.0275), respectivamente. Homens com osteoporose demonstraram níveis significativamente maiores de paratormônio (p = 0.0065). Não houve diferença significativa nos níveis de testosterona e calcitonina. Conclusão Existem diferenças hormonais entre os gêneros na osteoporose. Em mulheres, níveis significativamente menores de estradiol e vitamina D e, nos homens, níveis significativamente maiores de paratormônio, parecem influenciar na doença.

Immunosensor Based on Zinc Oxide Nanocrystals Decorated with Copper for the Electrochemical Detection of Human Salivary Alpha-Amylase.

(1) Background: Nanocrystals (NCs)-based electrochemical sensors have been proposed for biomarkers detection, although immunosensors using ZnO NCs decorated with copper are still scarce. (2) Methods: Electrochemical immunodetection of human salivary alpha-amylase (HSA) used ZnO, CuO, and ZnO:xCu (x = 0.1, 0.4, 1.0, 4.0, and 12.0) NCs. (3) Results: Substitutional incorporation of Cu2+ in the crystalline structure of ZnO and formation of nanocomposite were demonstrated by characterization. Graphite electrodes were used and the electrochemical signal increased by 40% when using ZnO:1Cu and 4Cu (0.25 mg·mL-1), in an immunosensor (0.372 mg·mL-1 of anti-alpha-amylase and 1% of casein). Different interactions of HSA with the alpha-amylase antibody were registered when adding the NCs together, either before or after the addition of saliva (4 µL). The immunosensor changed specificity due to the interaction of copper. The ZnO:1Cu and ZnO:4Cu samples showed 50% interference in detection when used before the addition of saliva. The immunosensor showed 100% specificity and a sensitivity of 0.00196 U·mL-1. (4) Conclusions: Results showed that the order of NCs addition in the sensors should be tested and evaluated to avoid misinterpretation in detection and to enable advances in the validation of the immunosensor.

IgG Subclass Analysis in Patients with Chagas Disease 4 Years After Benznidazole Treatment.

BACKGROUND: In humans, Trypanosoma cruzi infection is controlled by a complex immune response. Immunoglobulin G (IgG) is important for opsonizing blood trypomastigotes, activating the classic complement pathway, and reducing parasitemia. The trypanocidal activity of benznidazole is recognized, but its effects on the prevention and progression of Chagas disease is not well understood OBJECTIVE: We aimed to evaluate the levels of total IgG and cross-specific IgG subclasses in patients with chronic Chagas disease of different clinical forms before and after 4 years of benznidazole treatment. METHODS: Eight individuals with the indeterminate form and nine with the cardiac form who completed the treatment protocol were evaluated. The levels of total IgG and IgG1, IgG2, IgG3, and IgG4 isotypes were quantified in the serum of each individual using the fluorescent immunosorbent assay. The results are expressed as relative fluorescence unit. RESULTS: Patients with chronic Chagas disease presented decreased levels of total IgG at 48 months after benznidazole treatment. Increased IgG1 and decreased IgG3 levels were observed in patients with the cardiac form and those with exacerbated clinical forms. In addition, a decrease in the IgG3/IgG1 ratio was observed in individuals with the cardiac form of Chagas disease. CONCLUSIONS: Benznidazole administration in the chronic phase differentially changes IgG subclasses in patients with cardiac and indeterminate forms, and monitoring the IgG3 level may indicate the possible prognosis to the cardiac form or worsening of the already established clinical form.

2,2,2-trifluoro-1-(1,4,5,6-tetrahydropyridin-3-yl)ethanone derivative as efflux pump inhibitor in Mycobacterium tuberculosis.

Although the administration of combined therapy is efficient to tuberculosis (TB) treatment caused by susceptible Mycobacterium tuberculosis strains, to overcome the multidrug resistance is still a challenge. Some studies have reported evidence about tetrahydropyridines as a putative efflux pump inhibitor, including in mycobacteria, being a promising strategy against M. tuberculosis. Thus, we investigated the biological potential of 2,2,2-trifluoro-1-(1,4,5,6-tetrahydropyridin-3-yl)ethanone derivative (NUNL02) against two strains of M. tuberculosis. NUNL02 was able to increase the susceptibility of the multidrug resistant strain to the anti-TB drugs, resulting in synergism with rifampicin. Still, we assume that this compound plays a role in the efflux mechanism in M. tuberculosis, besides, to be able to kill the bacillus under the deprivation of essential nutrients. Thus, our findings highlight NUNL02 as a promising prototype to develop a new adjuvant for TB treatment, mainly as EPI.

Reverse vaccinology and subtractive genomics approaches for identifying common therapeutics against Mycobacterium leprae and Mycobacterium lepromatosis.

BACKGROUND: Mycobacterium leprae and Mycobacterium lepromatosis are gram-positive bacterial pathogens and the causative agents of leprosy in humans across the world. The elimination of leprosy cannot be achieved by multidrug therapy alone, and highlights the need for new tools and drugs to prevent the emergence of new resistant strains. METHODS: In this study, our contribution includes the prediction of vaccine targets and new putative drugs against leprosy, using reverse vaccinology and subtractive genomics. Six strains of Mycobacterium leprae and Mycobacterium lepromatosis (4 and 2 strains, respectively) were used for comparison taking Mycobacterium leprae strain TN as the reference genome. Briefly, we used a combined reverse vaccinology and subtractive genomics approach. RESULTS: As a result, we identified 12 common putative antigenic proteins as vaccine targets and three common drug targets against Mycobacterium leprae and Mycobacterium lepromatosis. Furthermore, the docking analysis using 28 natural compounds with three drug targets was done. CONCLUSIONS: The bis-naphthoquinone compound Diospyrin (CID 308140) obtained from indigenous plant Diospyros spp. showed the most favored binding affinity against predicted drug targets, which can be a candidate therapeutic target in the future against leprosy.

Knowledge About COVID-19 in Brazil: Cross-Sectional Web-Based Study.

BACKGROUND: COVID-19 is a highly transmissible illness caused by SARS-CoV-2. The disease has affected more than 200 countries, and the measures that have been implemented to combat its spread, as there is still no vaccine or definitive medication, have been based on supportive interventions and drug repositioning. Brazil, the largest country in South America, has had more than 140,000 recorded deaths and is one of the most affected countries. Despite the extensive quantity of scientifically recognized information, there are still conflicting discussions on how best to face the disease and the virus, especially with regard to social distancing, preventive methods, and the use of medications. OBJECTIVE: The main purpose of this study is to evaluate the Brazilian population's basic knowledge about COVID-19 to demonstrate how Brazilians are managing to identify scientifically proven information. METHODS: A cross-sectional study design was used. An original online questionnaire survey was administered from June 16 to August 21, 2020, across all five different geopolitical regions of the country (ie, the North, Northeast, Center-West, Southeast, and South). The questionnaire was comprised of questions about basic aspects of COVID-19, such as the related symptoms, conduct that should be followed when suspected of infection, risk groups, prevention, transmission, and social distancing. The wrong questionnaire response alternatives were taken from the fake news combat website of the Brazilian Ministry of Health. Participants (aged ≥18 years) were recruited through social networking platforms, including Facebook, WhatsApp, and Twitter. The mean distributions, frequencies, and similarities or dissimilarities between the responses for the different variables of the study were evaluated. The significance level for all statistical tests was less than .05. RESULTS: A total of 4180 valid responses representative of all the states and regions of Brazil were recorded. Most respondents had good knowledge about COVID-19, getting an average of 86.59% of the total score with regard to the basic aspects of the disease. The region, education level, age, sex, and social condition had a significant association (P<.001) with knowledge about the disease, which meant that women, the young, those with higher education levels, nonrecipients of social assistance, and more economically and socially developed regions had more correct answers. CONCLUSIONS: Overall, Brazilians with social media access have a good level of basic knowledge about COVID-19 but with differences depending on the analyzed subgroup. Due to the limitation of the platform used in carrying out the study, care should be taken when generalizing the study findings to populations with less education or who are not used to accessing social networking platforms.

Salivary and Intestinal Transcriptomes Reveal Differential Gene Expression in Starving, Fed and Trypanosoma cruzi-Infected Rhodnius neglectus.

Rhodnius neglectus is a potential vector of Trypanosoma cruzi (Tc), the causative agent of Chagas disease. The salivary glands (SGs) and intestine (INT) are actively required during blood feeding. The saliva from SGs is injected into the vertebrate host, modulating immune responses and favoring feeding for INT digestion. Tc infection significantly alters the physiology of these tissues; however, studies that assess this are still scarce. This study aimed to gain a better understanding of the global transcriptional expression of genes in SGs and INT during fasting (FA), fed (FE), and fed in the presence of Tc (FE + Tc) conditions. In FA, the expression of transcripts related to homeostasis maintenance proteins during periods of stress was predominant. Therefore, the transcript levels of Tret1-like and Hsp70Ba proteins were increased. Blood appeared to be responsible for alterations found in the FE group, as most of the expressed transcripts, such as proteases and cathepsin D, were related to digestion. In FE + Tc group, there was a decreased expression of blood processing genes for insect metabolism (e.g., Antigen-5 precursor, Pr13a, and Obp), detoxification (Sult1) in INT and acid phosphatases in SG. We also found decreased transcriptional expression of lipocalins and nitrophorins in SG and two new proteins, pacifastin and diptericin, in INT. Several transcripts of unknown proteins with investigative potential were found in both tissues. Our results also show that the presence of Tc can change the expression in both tissues for a long or short period of time. While SG homeostasis seems to be re-established on day 9, changes in INT are still evident. The findings of this study may be used for future research on parasite-vector interactions and contribute to the understanding of food physiology and post-meal/infection in triatomines.

Metabolic and immunological evaluation of patients with indeterminate and cardiac forms of Chagas disease.

ABSTRACT: Chagas disease affects approximately 7 million people, causing disability and mortality in the most productive life stages of infected individuals. Considering the lifestyle of the world population, metabolic syndrome is a synergistic factor for an increased cardiovascular risk of patients with Chagas disease.This study transversally evaluated the metabolic and immunological profiles of patients with indeterminate (IF) and cardiac (CF) forms of Chagas disease and their correlations with left ventricular dysfunction (LVD).Clinical and electrical bioimpedance analysis, levels of cytokines (interferon [IFN]-γ, tumor necrosis factor [TNF]-α, interleukin [IL]-17, IL-10, and IL-33) and adipocytokines (adiponectin, leptin, and resistin), metabolic syndrome components, and brain natriuretic peptide (BNP) levels were assessed in 57 patients (13 IF and 44 CF) with a mean age of 61.63 ±â€Š12.1 years. Chest x-ray, electrocardiogram, and echocardiogram were performed to classify the clinical forms.The CF group had a higher number of individuals with metabolic syndrome components blood pressure altered, while more participants in the CF group with LVD had low high-density lipoprotein (HDL) levels. The IF group had more participants with a higher waist-to-hip ratio (WHR). No significant difference was observed between metabolic syndrome, cytokine and adipocytokine level, and clinical forms of the disease or in relation to LVD.Individuals with the IF showed metabolic and immunological profiles compatible with increased disease control, whereas those with CF showed marked inflammatory immune response.

Corrigendum: Polymorphisms in Genes Affecting Interferon-γ Production and Th1 T Cell Differentiation Are Associated With Progression to Chagas Disease Cardiomyopathy.

[This corrects the article DOI: 10.3389/fimmu.2020.01386.].

Polymorphisms in Genes Affecting Interferon-γ Production and Th1 T Cell Differentiation Are Associated With Progression to Chagas Disease Cardiomyopathy.

Background: Chagas disease, caused by the protozoan Trypanosoma cruzi, is endemic in Latin America. Thirty percent of infected individuals develop chronic Chagas cardiomyopathy (CCC), an inflammatory dilated cardiomyopathy that is the most important clinical consequence of T. cruzi infection, while the others remain asymptomatic (ASY). IFN-γ and IFN-γ-producing Th1-type T cells are increased in peripheral blood and CCC myocardium as compared to ASY patients, while the Th1-antagonizing cytokine IL-10 is more expressed in ASY patients. Importantly IFN-γ-producing Th1-type T cells are the most frequent cytokine-producing T cell subset in CCC myocardium, while expression of Th1-antagonizing cytokines IL-10 and IL-4 is unaltered. The control of IFN-γ production by Th1-type T cells may be a key event for progression toward CCC. A genetic component to disease progression was suggested by the familial aggregation of cases and the association of gene polymorphisms with CCC development. We here investigate the role of gene polymorphisms (SNPs) in several genes involved in the control of IFN-γ production and Th1 T cell differentiation in CCC development. Methods: We studied a Brazilian population including 315 CCC cases and 118 ASY subjects. We assessed 35 Tag SNPs designed to represent all the genetic information contained in the IL12B, IL10, IFNG, and IL4 genes. Results: We found 2 IL12 SNPs (rs2546893, rs919766) and a trend of association for a IL10 SNP (rs3024496) to be significantly associated with the ASY group. these associations were confirmed by multivariate analysis and allele tests. The rs919766C, 12rs2546893G, and rs3024496C alleles were associated to an increase risk to CCC development. Conclusions: Our data show that novel polymorphisms affecting IL12B and IL10, but not IFNG or IL4 genes play a role in genetic susceptibility to CCC development. This might indicate that the increased Th1 differentiation and IFN-γ production associated with CCC is genetically controlled.

Development of an Electrochemical Immunosensor for Specific Detection of Visceral Leishmaniasis Using Gold-Modified Screen-Printed Carbon Electrodes.

Visceral leishmaniasis is a reemerging neglected tropical disease with limitations for its diagnosis, including low concentration of antibodies in the serum of asymptomatic patients and cross-reactions. In this context, this work proposes an electrochemical immunosensor for the diagnosis of visceral leishmaniasis in a more sensitive way that is capable of avoiding cross-reaction with Chagas disease (CD). Crude Leishmania infantum antigens tested in the enzyme-linked immunosorbent assay (ELISA) were methodologically standardized to best engage to the sensor. The antibodies anti-Trypanosoma cruzi and anti-Leishmania sp. Present in serum from patients with diverse types of CD or leishmaniasis were chosen. A screen-printed carbon electrode modified with gold nanoparticles was the best platform to guarantee effective adsorption of all antigens so that the epitope of specific recognition for leishmaniasis occurred efficiently and without cross-reaction with the evaluated CD. The current peaks reduced linearly after the recognition, and still were able to notice the discrimination between different kinds of diseases (digestive, cardiac, undetermined Chagas/acute and visceral chronic leishmaniasis). Comparative analyses with ELISA were performed with the same groups, and a low specificity (44%) was verified due to cross-reactions (high number of false positives) on ELISA tests, while the proposed immunosensor presented high selectivity and specificity (100%) without any false positives or false negatives for the serum samples from isolated patients with different types of CD and visceral leishmaniasis. Furthermore, the biosensor was stable for 5 days and presented a detection limit of 200 ng mL-1.

Effects of Meglumine Antimoniate Treatment on Cytokine Production in a Patient with Mucosal Leishmaniasis and Chagas Diseases Co-Infection.

The influence of antimoniate treatment on specific anti-protozoan T-cell responses was evaluated in a 48-year-old male patient diagnosed with mucosal leishmaniasis and Chagas disease infection. Before and after treatment, PBMC (peripheral blood mononuclear cells) were cultured in the absence or presence of Leishmania braziliensis or Trypanosoma cruzi live parasites, their soluble antigens, or PHA (phytohaemagglutinin). Cytokines were measured and Treg (T regulatory) cell percentages were quantified. Before treatment, PBMC were able to produce higher amounts of TNF-α, IL-6 (Interleukin-6), and IL-10 (Interleukin-10) but lower amounts of IL-12 (Interleukin-12) in response to culture stimulation. However, after treatment, there was a down-modulation of TNF-α, IL-6, and IL-10 cytokines but an up-modulation in IL-12 production. PBMC had the ability to produce TNF-α only against live parasites or PHA. There was an overall decrease of circulating Treg cells after treatment. In mixed Leishmaniasis and Chagas disease infection, treatment with antimoniate could modulate immune responses toward a more protective profile to both diseases.