Synthetic peptides elicit strong cellular immunity in Visceral Leishmaniasis natural reservoir and contribute to long-lasting polyfunctional T-cells in BALB/c mice.

Reverse vaccinology or immunoinformatics is a computational methodology which integrates data from in silico epitope prediction, associated to other important information as, for example, the predicted subcellular location of the proteins used in the design of the context of vaccine development. This approach has the potential to search for new targets for vaccine development in the predicted proteome of pathogenic organisms. To date, there is no effective vaccine employed in vaccination campaigns against visceral leishmaniasis (VL). For the first time, herein, an in silico, in vitro, and in vivo peptide screening was performed, and immunogenic peptides were selected to constitute VL peptide-based vaccines. Firstly, the screening of in silico potential peptides using dogs naturally infected by L. infantum was conducted and the peptides with the best performance were selected. The mentioned peptides were used to compose Cockt-1 (cocktail 1) and Cockt-2 (cocktail 2) in combination with saponin as the adjuvant. Therefore, tests for immunogenicity, polyfunctional T-cells, and the ability to induce central and effector memory in T-lymphocytes capacity in reducing the parasite load on the spleen for Cockt-1 and Cockt-2 were performed. Among the vaccines under study, Cockt-1 showed the best results, eliciting CD4+ and CD8+ polyfunctional T-cells, with a reduction in spleen parasitism that correlates to the generation of T CD4+ central memory and T CD8+ effector memory cells. In this way, our findings corroborate the use of immunoinformatics as a tool for the development of future vaccines against VL

Design and baseline characteristics of the finerenone in reducing cardiovascular mortality and morbidity in diabetic kidney disease trial

Background: Among people with diabetes, those with kidney disease have exceptionally high rates of cardiovascular (CV) morbidity and mortality and progression of their underlying kidney disease. Finerenone is a novel, nonsteroidal, selective mineralocorticoid receptor antagonist that has shown to reduce albuminuria in type 2 diabetes (T2D) patients with chronic kidney disease (CKD) while revealing only a low risk of hyperkalemia. However, the effect of finerenone on CV and renal outcomes has not yet been investigated in long-term trials. Patients and Methods: The Finerenone in Reducing CV Mortality and Morbidity in Diabetic Kidney Disease (FIGARO-DKD) trial aims to assess the efficacy and safety of finerenone compared to placebo at reducing clinically important CV and renal outcomes in T2D patients with CKD. FIGARO-DKD is a randomized, double-blind, placebo-controlled, parallel-group, event-driven trial running in 47 countries with an expected duration of approximately 6 years. FIGARO-DKD randomized 7,437 patients with an estimated glomerular filtration rate >= 25 mL/min/1.73 m(2) and albuminuria (urinary albumin-to-creatinine ratio >= 30 to <= 5,000 mg/g). The study has at least 90% power to detect a 20% reduction in the risk of the primary outcome (overall two-sided significance level alpha = 0.05), the composite of time to first occurrence of CV death, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for heart failure. Conclusions: FIGARO-DKD will determine whether an optimally treated cohort of T2D patients with CKD at high risk of CV and renal events will experience cardiorenal benefits with the addition of finerenone to their treatment regimen. Trial Registration: EudraCT number: 2015-000950-39; ClinicalTrials.gov identifier: NCT02545049

Plasmodium berghei NK65 induces cerebral leukocyte recruitment in vivo : an intravital microscopic study.

Malaria is second only to tuberculosis as the leading cause of morbidity and mortality as a consequence of a single infectious agent. Much of the pathology of malaria arises from the inappropriate or excessive immune response mounted by the host in an attempt to eliminate the parasite. We here report the inflammatory changes observed in the cerebral microvasculature of C57BL/6 and BALB/c mice that had been inoculated with Plasmodium berghei NK65, a lethal strain of rodent malaria. Although no neurological signs were observed in experimentally infected mice, inflammation of the cerebral microvasculature was clearly evident. Histopathological analysis demonstrated that alterations in cerebral tissue were more intense in infected C57Bl/6 mice than in infected BALB/c animals. Intravital microscopic examination of the cerebral microvasculature revealed increased leukocyte rolling and adhesion in pial venules of infected mice compared with non-infected animals. The extravasation of Evans blue dye into the cerebral parenchyma was also elevated in infected mice in comparison with their non-infected counterparts. Additionally, protein levels of TNF-_, MIG/CXCL9, MCP-1/CCL2, MIP-1_/CCL3 and RANTES/CCL5 were up-regulated in brain samples derived from infected C57Bl/6 mice. Taken together, the data reported here illustrate the complex strain-dependent relationships between leukocyte recruitment, blood brain barrier permeability and chemokine production

Systemic and compartmentalized immune response in canine visceral leishmaniasis.

Human visceral leishmaniasis (VL) and canine visceral leishmaniasis (CVL) are the most important emerging diseases with high prevalence in Latin American countries and are mainly caused by Leishmania (L.) chagasi (Syn = L. infantum). CVL has a great impact on Brazilian public health because domestic dogs are the most important VL peri-domicile reservoirs in both urban and peri-urban areas. Our findings highlight the complexity of cellular immunological events related to the natural infection from dogs by L. chagasi, additionally correlating major peripheral blood phenotypic markers with clinical status and tissues parasite density. Our main results demonstrated that lower frequency ofcirculating B cells and monocytes are important markers of severe CVL, whereas increased levels of CD8+ lymphocytes appear to be the major phenotypic feature of asymptomatic disease. Determination of the isotypes patterns during CVL demonstrated thatasymptomatic dogs and those with low parasitism are associated with an increase of IgG1, while the symptomatic dogs and those with high parasitism are associated with an increase of IgG, IgG2, IgM, IgA and IgE immunoglobulins. Pioneer findings obtained by our group showed a correlation between clinical status of CVL with degree of tissue parasite density. This data demonstrated that asymptomatic dogs presented low parasitism while symptomatic dogs are associated with high parasite load in various tissues such as skin, bone marrow and spleen. We have also investigated the association between tissue parasitism and CVL clinical forms. Regardless of clinical status, skin and spleen are the major sites of high parasite density during ongoing CVL. Furthermore, we demonstrated that bone marrow and spleen parasite density are the most reliable parasitological markers to decode the clinical status of CVL. In this article, we have reviewed some aspectsof the histopathological and immunological events occurring in natural and experimentalL. chagasi/L. infantum infection, pointing out the main L. chagasi-parasitized tissue. Wehave discussed the importance of the association between parasite density, immunological/ histopathological aspects and clinical status of the CVL, their current applications, challenges for the future and potential opportunities in CVL research

Benznidazole treatment during early indeterminate Chagas' disease shifted the cytokine expression by innate and adaptive immunity cells toward a type-1 modulated immune profile.

Trypanosoma cruzi-infected children was treated with benznidazole (Bz) duringthe early-indeterminate disease (E-IND) and the cytokine pattern of innate andadaptive immune compartments were evaluated prior to the treatment and1 year after it. At first, we observed that the ex vivo cytokine profile of circula-ting leukocytes from E-IND (n ? 6) resembled the one observed for healthyschoolchildren (n ? 7). Additionally, in vitro stimulation with T. cruzi anti-gens drove the E-IND cytokine pattern toward a mixed immune profile withhigher levels of IFN-c+, TNF-a+and IL-4+NK cells, increased numbers ofIFN-c+, TNF-a+and IL-10+CD4+T cells in addition to enhanced frequencyof TNF-a+/IL-4+CD19+lymphocytes. Interestingly, upon T. cruzi antigen invitro stimulation, E-IND CD8+lymphocytes displayed a selective enhancementof IFN-c expression, accounting for a global type 1-modulated cytokine micro-environment. A shift toward a type 1-modulated profile was also the hallmarkof Bz-treated children (E-INDT). In this context, despite the mixed overall exvivo cytokine profile observed for NK and CD8+T cells, incr eased ability ofthese leukocytes to produce IFN-c in respons e to T. cruzi antigens was repor-ted. Most noteworthy was the IL-10 production evidenced at T lymphocytes,mainly CD4+cells, as well as B lymphocytes, both ex vivo and upon antigenstimulation. Toget her, these findings gave evidence that NK cells and CD8+T lymphocytes are the major sources of IFN-c, a pivotal cytokine for successfultherapeutic response in human Chagas? disease. Moreover, our data have alsobrought additional information, pointing out IL-10 production by CD4+cellsand B lymphocytes, as the putative key element for parasite clearance in theabsence of deleterious tissue damage

Multiplex flow cytometry serology to diagnosis of canine visceral leishmaniasis.

An accurate diagnosis of visceral leishmaniasis is an essential tool for control of the disease. While serologic methods are very useful, these conventional methodologies still present limitations in terms of sensitivity and specificity. The use of flow cytometry is a worldwide trend in the development of high-performance diagnostic methods. Herein, we describe a new flow cytometry serology test, characterized by the employment of the Cytometric Bead Array microspheres A4 and E4 coated with the recombinant antigens rLci1A and rLci2B respectively, to improve the serodiagnosis of canine visceral leishmaniasis. The tests were conducted in a wide variety of sera groups (n = 140), where the diagnostics development would be optimized accounting not just the ability to identify infected dogs with different clinical status, but also to exclude cross-reaction and differentiate vaccinated dogs from dogs infected. Serological testing of the antigenic system A4?rLci1A showed a sensitivity of 90.0% and specificity of 75%, while the E4?rLci2B testing demonstrated a sensitivity of 95.0% and specificity of 82.5%. The use of a multiplex assay of A4?rLci1A and E4?rLci2B, resulted in a diagnostic improvement, with a sensitivity of 95.0% and specificity of 91.2%. Our results show that this novel flow cytometry serology test is a viable tool for sensitive and specific serodiagnosis. Notably, the combination of distinct antigenic systems allows us to test for antibodies to multiple recombinant antigens from a single serum sample. This benefit emphasizes the importance of this methodology as an alternative in the serological diagnosis