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1.
Trop Med Infect Dis ; 8(11)2023 Nov 09.
Article in English | MEDLINE | ID: mdl-37999614

ABSTRACT

Asymptomatic Leishmania infantum, when associated with HIV, can become severe and potentially fatal. In this co-infection, the worst prognosis may be influenced by the host's immunological aspects, which are crucial in determining susceptibility. Chemokines play an important role in this process by influencing the cellular composition at affected sites and impacting the disease's outcome. Therefore, the aim of this study was to evaluate proinflammatory chemokines in HIV patients with the asymptomatic L. infantum infection. In this cross-sectional study, the levels of CCL2, CCL5, CXCL8, MIG, and IP-10 were measured in 160 serum samples from co-infected patients (n = 53), patients with HIV (n = 90), and negative controls (n = 17). Quantification was determined by flow cytometry. The obtained data were statistically analyzed using the Kruskal-Wallis test, followed by the Dunn's post-test and the Spearman's correlation coefficient. Significance was set at p < 0.05. The chemokines CCL2, CCL5, MIG, and IP-10 exhibited higher levels in the HIV group compared to co-infection. However, the elevated levels of all these chemokines and their increased connectivity in co-infected patients appear to be important in identifying proinflammatory immune responses associated with the asymptomatic condition. Furthermore, a weak negative correlation was observed between higher levels of CXCL8 and lower viral loads in co-infected patients.

2.
PLoS Pathog ; 15(4): e1007721, 2019 04.
Article in English | MEDLINE | ID: mdl-31009499

ABSTRACT

The need for improved dengue vaccines remains since the only licensed vaccine, Dengvaxia, shows variable efficacy depending on the infecting dengue virus (DENV) type, and increases the risk of hospitalization for severe dengue in children not exposed to DENV before vaccination. Here, we developed a tetravalent dengue purified and inactivated vaccine (DPIV) candidate and characterized, in rhesus macaques, its immunogenicity and efficacy to control DENV infection by analyzing, after challenge, both viral replication and changes in biological markers associated with dengue in humans. Although DPIV elicited cross-type and long-lasting DENV-neutralizing antibody responses, it failed to control DENV infection. Increased levels of viremia/RNAemia (correlating with serum capacity at enhancing DENV infection in vitro), AST, IL-10, IL-18 and IFN-γ, and decreased levels of IL-12 were detected in some vaccinated compared to non-vaccinated monkeys, indicating the vaccination may have triggered antibody-dependent enhancement of DENV infection. The dengue macaque model has been considered imperfect due to the lack of DENV-associated clinical signs. However, here we show that post-vaccination enhanced DENV infection can be detected in this model when integrating several parameters, including characterization of DENV-enhancing antibodies, viremia/RNAemia, and biomarkers relevant to dengue in humans. This improved dengue macaque model may be crucial for early assessment of efficacy and safety of future dengue vaccines.


Subject(s)
Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , Dengue Vaccines/immunology , Dengue Virus/immunology , Dengue/immunology , Vaccines, Inactivated/immunology , Viremia/immunology , Animals , Antibody-Dependent Enhancement , Dengue/prevention & control , Dengue/virology , Dengue Vaccines/administration & dosage , Disease Models, Animal , Female , Macaca mulatta , Male , Vaccination , Viremia/virology
3.
PLoS One ; 13(4): e0196311, 2018.
Article in English | MEDLINE | ID: mdl-29694440

ABSTRACT

The macaque is widely accepted as a suitable model for preclinical characterization of dengue vaccine candidates. However, the only vaccine for which both preclinical and clinical efficacy results were reported so far showed efficacy levels that were substantially different between macaques and humans. We hypothesized that this model's predictive capacity may be improved using recent and minimally passaged dengue virus isolates, and by assessing vaccine efficacy by characterizing not only the post-dengue virus challenge viremia/RNAemia but also the associated-cytokine profile. Ten recent and minimally passaged Brazilian clinical isolates from the four dengue virus serotypes were tested for their infectivity in rhesus macaques. For the strains showing robust replication capacity, the associated-changes in soluble mediator levels, and the elicited dengue virus-neutralizing antibody responses, were also characterized. Three isolates from dengue virus serotypes 1, 2 and 4 induced viremia of high magnitude and longer duration relative to previously reported viremia kinetics in this model, and robust dengue virus-neutralizing antibody responses. Consistent with observations in humans, increased MCP-1, IFN-γ and VEGF-A levels, and transiently decreased IL-8 levels were detected after infection with the selected isolates. These results may contribute to establishing a dengue macaque model showing a higher predictability for vaccine efficacy in humans.


Subject(s)
Dengue Virus/immunology , Dengue/pathology , Animals , Antibodies, Neutralizing/blood , Antibodies, Viral/blood , Brazil , Chemokine CCL2/metabolism , Chlorocebus aethiops , Dengue/veterinary , Dengue Virus/isolation & purification , Down-Regulation , Interferon-gamma/metabolism , Interleukin-8 , Macaca mulatta , Serogroup , Up-Regulation , Vascular Endothelial Growth Factor A/metabolism , Vero Cells
4.
RBM rev. bras. med ; 48(5): 246-8, 250, maio 1991. tab
Article in Portuguese | LILACS | ID: lil-101247

ABSTRACT

O autor propöe, através da experiência de 13 meses de observaçäo na Unidade de Saúde da Serra Talhada, PE, da Fundaçäo Serviços de Saúde Pública, uma associaçäo de colpocitologia oncótica, prova de SCHILLER, colposcopia e histopatologia no Programa de Prevençäo do Câncer Cérvico-Uterino, elaborando uma rotina de triagem para a colposcopia a partir da prova de SCHILLER e citopatologia. Tal associaçäo de métodos tem como objetivo principal a diminuiçäo de índice falso-negativo, verificado quando se aplica algum dos métodos isoladamente. De um total de 1.121 mulheres examinadas, 10 delas, 0,9%, tiveram resultados citopatológico positivo, enquanto que ao se utilizar a rotina proposta associando-se os métodos, encontramos 23(2,0%) com diagnósticos compátiveis com neoplasia cervical


Subject(s)
Humans , Female , Adult , Middle Aged , Uterine Cervical Neoplasms/prevention & control , Colposcopy , Cytodiagnosis , Health Centers , Uterine Cervical Neoplasms/diagnosis
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