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Background: In recent years, HIV self-testing (HIVST) has emerged as a promising approach to enhance accessibility and uptake of HIV testing, particularly among populations at high risk for sexually transmitted infections (STIs). Despite its potential benefits, the effectiveness, and challenges of HIVST warrant careful examination to inform public health strategies effectively. This study investigates the effectiveness and challenges of HIV self-testing (HIVST) in populations at high risk for sexually transmitted infections (STIs). Study design : Cross-sectional study., Methods: We employed questionnaires, HIVST, and standard tests for HIV, Hepatitis C, and Syphilis, in patients exhibiting STI risk behaviors in Belo Horizonte, Brazil, between August and November of 2019., Results: We engaged 125 individuals, median age of 33.5 years, with most participants (61 %) deviating significantly during self-testing. Despite this, HIVST was generally perceived as user-friendly. From the perspective of health professionals, there was 100 % agreement between HIVST and the gold standard HIV testing results. Notably, among those seeking solely HIV testing, 19.2 % tested positive for Syphilis, and 4.8 % for Hepatitis C. Only a minority (4.8 %) were aware of the HIV window period., Conclusion: While HIVST presents benefits, the evidence does not yet support its widespread adoption as a standalone public health policy. Moreover, exclusive reliance on HIVST might mask the prevalence of other STIs. We advocate for a holistic approach to HIV and STI testing, incorporating education, counseling, and comprehensive healthcare access in public health initiatives., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Introduction: The scarcity of suitable donor organs has led to the inclusion of Expanded Criteria Donor (ECD) kidneys to augment the donor pool, despite potential concerns regarding post-transplant outcomes., Methods: This retrospective study analyzed the clinical outcomes of a cohort of 317 kidney transplant recipients from deceased donors at a single center between 2008 and 2018. Patients were categorized into ECD and Standard Criteria Donor (SCD) groups, with primary nonfunctioning grafts excluded. Comprehensive laboratory evaluations were conducted, including HLA typing and serum creatinine levels. Immunosuppressive regimens were standardized, and statistical analyses were performed using the SPSS program., Results: The sample consisted of 83 (26.18%) patients who received kidney transplants from ECDs and 234 (73.82%) from SCDs. The ECD group showed a longer cold ischemia time (p = 0.019) and a higher rate of delayed graft function (DGF) compared with the SCD group. No significant differences were observed in graft survival (p = 0.370) or patient survival (p = 0.993) between the ECD and SCD groups. However, differences in graft survival were noted between the groups when stratified by DGF status: ECD with DGF vs. ECD without DGF (p = 0.029), ECD with DGF vs. SCD with DGF (p = 0.188), ECD with DGF vs. SCD without DGF (p = 0.022), ECD without DGF vs. SCD with DGF (p = 0.014), ECD without DGF vs. SCD without DGF (p = 0.340), and SCD with DGF vs. SCD without DGF (p = 0.195). No differences in patient survival rates were observed among these groups for all pairwise comparisons (p > 0.05) when stratified by donor criteria and DGF status., Conclusions: Graft and patient survival rates were comparable between ECD and SCD kidney transplant recipients., Competing Interests: Declaration of competing interest The authors declare that there are no conflicts of interest., (Copyright © 2024. Published by Elsevier B.V.)

Introduction: Chagas disease is a neglected parasitic disease caused by Trypanosoma cruzi . While most patients are asymptomatic, around 30% develop Chronic Chagasic Cardiomyopathy (CCC)., Methods: 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., Results: 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., Discussion: Taken together, our results showed that T. cruzi 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., Conclusion: 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., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The reviewer TS declared a shared affiliation with the author(s) MO, SE to the handling editor at the time of review., (Copyright © 2024 Vale, Almeida, Rimkute, Liechti, Araújo, Santos, Henriques, Rocha, Elói-Santos, Martins−Filho, Roederer, Sher, Jankovic, Teixeira−Carvalho and Antonelli.)

The re-emergence of yellow fever (YF) urged new mass vaccination campaigns and, in 2017, the World Health Organization approved the use of the fractional dose (FD) of the YF vaccine due to stock shortage. In an observational cross-sectional investigation, we have assessed viremia, antibodies, soluble mediators and effector and memory T and B-cells induced by primary vaccination of volunteers with FD and standard dose (SD). Similar viremia and levels of antibodies and soluble markers were induced early after immunization. However, a faster decrease in the latter was observed after SD. The FD led to a sustained expansion of helper T-cells and an increased expression of activation markers on T-cells early after vaccination. Although with different kinetics, expansion of plasma cells was induced upon SD and FD immunization. Integrative analysis reveals that FD induces a more complex network involving follicular helper T cells and B-cells than SD. Our findings substantiate that FD can replace SD inducing robust correlates of protective immune response against YF., (© 2024. The Author(s).)

Doxorubicin (DOXO)-cardiotoxicity is a limiting factor for breast cancer chemotherapy. The relationship between microparticles (MPs) and cardiotoxicity remains unclear. MPs can be released under varying pathophysiological conditions. Thereby, this study aimed to assess MPs derived from cardiomyocytes (CardioMPs), platelets (PMPs) and those that expresses tissue factor (TFMPs) in 80 women with breast cancer undergoing DOXO-based chemotherapy, with or without cardiotoxicity in a one-year follow-up. We observed in the cardiotoxicity group higher count of total-MPs at T0 (prior chemotherapy) (p = 0.034), CardioMPs at T0 and T1 (just after chemotherapy) (p = 0.009 and p = 0.0034) and TFMPs at T0 (p = 0.011) compared to non-cardiotoxicity group. The results suggest that MPs could be associated to cardiotoxicity due to DOXO treatment in breast cancer patients., Competing Interests: Declaration of Competing Interest None., (Copyright © 2023. Published by Elsevier B.V.)

The COVID-19 pandemic has profoundly impacted individuals, resulting in long-lasting consequences. One of the effects has been a decline in vaccine adherence attributed to physical distancing measures, potentially contributing to the resurgence of preventable diseases, and posing diagnostic challenges. Consequently, monitoring immunization rates becomes crucial as an indicator for health promotion campaigns and to mitigate the strain on healthcare systems. This study aims to assess the effects of the COVID-19 pandemic on immunization with pneumococcal vaccines in children and older adults in Brazil from 2018 to 2021. Data was collected from the Department of Informatics of the Unified Health System, focusing on the number of doses administered and vaccination coverage with pneumococcal vaccines across the country. A total of 21,780,450 doses were administered, with a decline of 19.97% in vaccine coverage throughout the evaluation period. An overall negative trend was observed in the time series analysis for all states in Brazil. However, not all showed a statistically significant change associated with the pandemic. Therefore, it is essential for states that experienced a decline in vaccination rates during the COVID-19 pandemic to closely monitor changes in pneumococcal vaccination. Failure in the process may lead to an increase in pneumococcal infections and place an additional burden on the healthcare system., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Individuals with malaria exhibit increased morbidity and mortality when infected with Gram-negative (Gr-) bacteria. To explore this experimentally, we performed co-infection of mice with Plasmodium chabaudi and Citrobacter rodentium, an extracellular Gr- bacterial pathogen that infects the large intestine. While single infections are controlled effectively, co-infection results in enhanced virulence that is characterized by prolonged systemic bacterial persistence and high mortality. Mortality in co-infected mice is associated with disrupted iron metabolism, elevated levels of plasma heme, and increased mitochondrial reactive oxygen species (ROS) production by phagocytes. In addition, iron acquisition by the bacterium plays a key role in pathogenesis because co-infection with a mutant C. rodentium strain lacking a critical iron acquisition pathway does not cause mortality. These results indicate that disrupted iron metabolism may drive mortality during co-infection with C. rodentium and P. chabaudi by both altering host immune responses and facilitating bacterial persistence., Competing Interests: Declaration of Interests The authors declare no competing financial interests., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

In the present study we have evaluated the performance of several immunological biomarkers for early diagnosis and prognosis of congenital toxoplasmosis. Our results showed that ex vivo serum levels of CXCL9, and the frequencies of circulating CD4 + CD25 + T-cells and T. gondii-specific IFN-γ + CD4 + T-cells measured 30-45 days after birth presented high accuracy to distinguish T. gondii-infected infants from healthy age-matched controls (Global Accuracy/AUC = 0.9; 0.9 and 0.8, respectively). Of note was the enhanced performance (Accuracy = 96%) achieved by using a combined stepwise analysis of CD4 + CD25 + T-cells and CXCL9. In addition, high global accuracy (AUC = 0.9) with elevated sensitivity (Se = 98%) was also reached by using the total frequency of in vitro IFN-γ-producing T. gondii-specific T-cells (∑ IFN-γ + CD4 + & CD8 + ) as a biomarker of congenital toxoplasmosis. Furthermore, the analysis of in vitro T. gondii-specific IL5 + CD4 + T-cells and IFN-γ + NK-cells displayed a high accuracy for early prognosis of ocular lesion in infant with congenital toxoplasmosis (Global Accuracy/AUC = 0.8 and 0.9, respectively). Together, these findings support the relevance of employing the elements of the cell-mediated immune response as biomarkers with potential to endorse early diagnosis and prognosis of congenital ocular toxoplasmosis to contribute for a precise clinical management and effective therapeutic intervention.

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., (©2020 Society for Leukocyte Biology.)

The formation of thrombi in medical devices that come into contact with blood is a common cause of increased morbidity and mortality. Prolonged use of central venous catheters (CVCs) may cause high infection rates or compromise CVC patency due to thrombus development. In this study, we sought insights into possible changes in the hemostatic system during prolonged use of inserted CVCs for hemodialysis by assessing platelets by CD62P and CD41a expression and the potential for thrombin generation (TG). This study included patients with chronic renal failure who were undergoing hemodialysis three times a week using a CVC, and healthy subjects as controls. The participants were distributed into three groups: Group 1: clinically and laboratorially healthy individuals matched by sex and age to the patients (controls); Group II: patients who had completed 1 month of CVC insertion; and Group III: the same patients after they had completed 4 months of CVC insertion. Platelet activation analysis and TG evaluation were performed using blood samples obtained through two different accesses, that is, through a peripheral vein and directly from the CVC lumen. The data showed platelet activation and an increase in the generation of thrombin, particularly after 4 months of CVC use. The results also indicated that insertion of the catheter into the blood stream stimulated the intrinsic rather than the extrinsic pathway. Taken together, the data showed a direct relationship between the use of CVCs in hemodialysis patients and a state of hypercoagulability, most likely associated with endothelial damage and the contact of the medical device with blood components such as platelets and coagulation factors., (© 2019 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.)

The infection with the protozoan parasite Trypanosoma cruzi causes Chagas disease, a neglected tropical disease in Latin America and an imported emerging disease worldwide. Chronic Chagasic cardiomyopathy (CCC), a progressive inflammatory and fibrosing disease, is the most prominent clinical form of Chagas disease, culminating in heart failure and high rates of sudden death. CCC pathogenesis is influenced by both host and parasite factors and is proposed to be mostly immune-driven. Chemokines are crucial players in orchestrating immune cell recruitment to infected tissues and inflammation. Herein, we investigated inflammatory chemokine receptor expression on circulating T cells in patients stratified by CCC severity. Compared to asymptomatic individuals, we found increased percentages of effector CD4 + T cells and central memory CD4 + and CD8 + T cells expressing CCR5 in patients with structural cardiopathy, but normal global ventricular function and no symptoms of chronic heart failure. Even naïve T cells expressed CCR5 in these patients. In contrast, reduced frequencies of CD4 + and CD8 + effector T cells expressing CXCR3 were observed in patients presenting with severe heart disease. Patients with increased left ventricular diameter, heart enlargement, and insufficiency had higher frequencies of CCR5 + effector and effector memory CD8 + T cells. Moreover, the percentage of effector CCR5 + CD8 + T cells was increased in patients with a reduced ejection fraction. Our results show that high expression CCR5 and low expression of CXCR3 on circulating T cells are associated with worse prognosis, possibly reflecting immune-mediated cardiac remodeling of CCC., (©2019 Society for Leukocyte Biology.)

The development of cancer immunotherapy has long been a challenge. Here, we report that prophylactic vaccination with a highly attenuated Trypanosoma cruzi strain expressing NY-ESO-1 (CL-14-NY-ESO-1) induces both effector memory and effector CD8(+) T lymphocytes that efficiently prevent tumor development. However, the therapeutic effect of such a vaccine is limited. We also demonstrate that blockade of Cytotoxic T Lymphocyte Antigen 4 (CTLA-4) during vaccination enhances the frequency of NY-ESO-1-specific effector CD8(+) T cells producing IFN-γ and promotes lymphocyte migration to the tumor infiltrate. As a result, therapy with CL-14-NY-ESO-1 together with anti-CTLA-4 is highly effective in controlling the development of an established melanoma.

Properties like high interfacial area with cellular membranes, unique ability to incorporate multiple functionalization, as well as compatibility and transport in biological fluids make carbon nanotubes (CNTs) useful for a variety of therapeutic and drug-delivery applications. Here we used a totally synthetic hybrid supramolecule as an anticancer vaccine formulation. This complex structure comprises CNTs as delivery system for the Cancer Testis Antigen named NY-ESO-1, allied to a synthetic Toll-Like Receptor agonist. The CNT constructs were rapidly internalized into dendritic cells, both in vitro and in vivo, and served as an intracellular antigen depot. This property favored the induction of strong CD4(+) T as well as CD8(+) T cell-mediated immune responses against the NY-ESO-1. Importantly, the vaccination significantly delayed the tumor development and prolonged the mice survival, highlighting the potential application of CNTs as a vaccine delivery system to provide superior immunogenicity and strong protection against cancer.

In the present study we evaluated the protection raised by immunization with recombinant influenza viruses carrying sequences coding for polypeptides corresponding to medial and carboxi-terminal moieties of Trypanosoma cruzi ´s amastigote surface protein 2 (ASP2). Those viruses were used in sequential immunization with recombinant adenovirus (heterologous prime-boost immunization protocol) encoding the complete sequence of ASP2 (Ad-ASP2) in two mouse strains (C57BL/6 and C3H/He). The CD8 effector response elicited by this protocol was comparable to that observed in mice immunized twice with Ad-ASP2 and more robust than that observed in mice that were immunized once with Ad-ASP2. Whereas a single immunization with Ad-ASP2 sufficed to completely protect C57BL/6 mice, a higher survival rate was observed in C3H/He mice that were primed with recombinant influenza virus and boosted with Ad-ASP2 after being challenged with T. cruzi. Analyzing the phenotype of CD8+ T cells obtained from spleen of vaccinated C3H/He mice we observed that heterologous prime-boost immunization protocol elicited more CD8+ T cells specific for the immunodominant epitope as well as a higher number of CD8+ T cells producing TNF-α and IFN-γ and a higher mobilization of surface marker CD107a. Taken together, our results suggest that immunodominant subpopulations of CD8+ T elicited after immunization could be directly related to degree of protection achieved by different immunization protocols using different viral vectors. Overall, these results demonstrated the usefulness of recombinant influenza viruses in immunization protocols against Chagas Disease.