Comprehensive analysis of early T cell responses to acute Zika Virus infection during the first epidemic in Bahia, Brazil.

BACKGROUND: In most cases, Zika virus (ZIKV) causes a self-limited acute illness in adults, characterized by mild clinical symptoms that resolve within a few days. Immune responses, both innate and adaptive, play a central role in controlling and eliminating virus-infected cells during the early stages of infection. AIM: To test the hypothesis that circulating T cells exhibit phenotypic and functional activation characteristics during the viremic phase of ZIKV infection. METHODS: A comprehensive analysis using mass cytometry was performed on peripheral blood mononuclear cells obtained from patients with acute ZIKV infection (as confirmed by RT-PCR) and compared with that from healthy donors (HD). The frequency of IFN-γ-producing T cells in response to peptide pools covering immunogenic regions of structural and nonstructural ZIKV proteins was quantified using an ELISpot assay. RESULTS: Circulating CD4+ and CD8+ T lymphocytes from ZIKV-infected patients expressed higher levels of IFN-γ and pSTAT-5, as well as cell surface markers associated with proliferation (Ki-67), activation ((HLA-DR, CD38) or exhaustion (PD1 and CTLA-4), compared to those from HD. Activation of CD4+ and CD8+ memory T cell subsets, including Transitional Memory T Cells (TTM), Effector Memory T cells (TEM), and Effector Memory T cells Re-expressing CD45RA (TEMRA), was prominent among CD4+ T cell subset of ZIKV-infected patients and was associated with increased levels of IFN-γ, pSTAT-5, Ki-67, CTLA-4, and PD1, as compared to HD. Additionally, approximately 30% of ZIKV-infected patients exhibited a T cell response primarily directed against the ZIKV NS5 protein. CONCLUSION: Circulating T lymphocytes spontaneously produce IFN-γ and express elevated levels of pSTAT-5 during the early phase of ZIKV infection whereas recognition of ZIKV antigen results in the generation of virus-specific IFN-γ-producing T cells.

APOL1 genotyping via buccal mucosa cell samples to establish risk of kidney disease.

Two alleles (G1 and G2) of the apolipoprotein 1 gene (APOL1) predispose people of African descent to developing or accelerating the course of certain types of kidney disease. Population studies to determine the frequency of the G1 and G2 alleles are important to inform resource allocation by public health authorities. Traditionally, APOL1 genotyping is carried out in blood samples. However, sample collection, transport, and storage is cumbersome. Here we compared APOL1 genotyping in blood and buccal mucosa cell samples obtained from 23 individuals. Alleles G0 (wild), G1, and G2, as well as genotypes G0/G0, G0/G1, G1/G1, G0/G2, G1/G2, and G2/G2 were detected using both blood and buccal mucosa cells with 100% coincidence. Our data indicate that buccal mucosa cell samples may represent a suitable alternative to blood samples for APOL1 genotyping in the field.

Acute coronary syndrome: Relationship between genetic variants and TIMI risk.

Acute Coronary Syndrome (ACS) is a multifactorial disease, including the genetic factor, caused by coronary artery obstruction by atheroma. Some genetic variants have been described as risk factors for this disease. Its early diagnosis and stratification of risk of death by Thrombolysis in Myocardial Infarction (TIMI) are important. Therefore, we evaluated variants in the IL6R (c950-1722C>T), TNFa (c.-488G>A), LEPR (c.2673+1118C>T) and IL1b (c.-598T>C) genes in relation to TIMI risk, cytokine serum levels, and risk factors for ACS. We selected 200 patients with ACS, 50 without ACS from the Real Hospital Português, Recife - PE, and 295 blood donors at the Fundação de Hematologia e Hemoterapia de Pernambuco (Hemope). Variants were determined by DNA sequencing or enzymatic cleavage. Cytokine levels were measured by ELISA. The most frequent risk factors found in the patients were dyslipidemia and hypertension, this latter associated with high TIMI risk (p = 0.003). Genotype frequencies of IL6R and TNFa differed between patients with ACS and the blood donors (p = 0.0002 and p = 0.01, respectively), and TNF-α levels differed between genotypes. The TT genotype of the IL6R gene is as a possible protective factor for ACS because it was significantly more present in blood donors (32.2%) than in patients with ACS (18.0%), and was more frequent in low TIMI risk (22.9%) than in the intermediate (20.2%) or high (4.9%). In patients with ACS, the TT genotype in IL6R was related to a lower concentration of c-reactive protein (p = 0.03) and troponin (p = 0.02), showing a less inflammatory reaction and tissue damage. The differences in the frequencies of variants in genes of medical interest among the groups show the importance of studies in specific populations groups to establish the relationship between genes and diseases.

Avaliação do Polimorfismo -174 G/C do gene IL-6 na Síndrome Coronariana Aguda no Nordeste do Brasil / Evaluation of IL-6 (-174 G/C) Polymorphism in Acute Coronary Syndrome in the Northeast of Brazil

Fundamento: A síndrome coronariana aguda (SCA) é a principal causa de morbidade e mortalidade no mundo. É uma doença multifatorial causada por obstrução das artérias coronárias por placa ateromatosa que leva à isquemia cardíaca. Diversos estudos sugerem que alguns polimorfismos genéticos alteram os níveis de citocinas e influenciam o desenvolvimento de SCA. Objetivo: Neste estudo, avaliamos o polimorfismo - 174 G/C do gene IL-6 , níveis séricos de citocina e sua relação com SCA e escore de risco de thrombolysis in myocardial infarction (TIMI). Materiais e métodos: Foram selecionados 200 pacientes com SCA [risco de TIMI ­ Baixo (70), Intermediário (89), Alto (41)] na população brasileira. A genotipagem foi feita pela reação em cadeia da polimerase (PCR), seguida de sequenciamento de DNA. Resultados: Não houve diferenças significativas na distribuição dos genótipos (p = 0,53) e dos alelos (p = 0,32) entre grupos de pacientes com SCA e sem SCA no polimorfismo alélico do IL-6 , nem entre os três escores de risco TIMI (p > 0,05). Além disso, o polimorfismo do IL-6 não afetou os níveis de citocina, os quais não estavam relacionados ao escore de TIMI. Conclusões: Com esses resultados, sugerimos que o polimorfismo ­ 174 G/C do gene IL-6, até agora, não está relacionado à SCA e não alterou os níveis de citocina na população estudada. Novos estudos em populações diferentes devem ser feitos para verificar esses resultados. É importante enfatizar que, como a SCA é uma doença multifatorial, outros fatores de risco e outras citocinas pró-inflamatórias devem ser avaliadas para o conhecimento dessa patologia

Background: Acute coronary syndrome (ACS) is a leading cause of morbidity and mortality worldwide. It is a multifactorial disease caused by obstruction of the coronary arteries by atheromatous plaques and leads to heart ischemia. Several studies suggest that some genetic polymorphisms change the cytokines levels and influence ACS development. Objective: In this study, we evaluated the IL-6 polymorphism -174 G/C, serum levels of cytokine and its relationship with ACS and the thrombolysis in myocardial infarction (TIMI) risk score. Materials and Methods: A sample of 200 patients with ACS [TIMI risk ­ Low (70); Intermediate (89); High (41)] in Brazilian population was used. Genotyping was carried out by polymerase chain reaction, followed by DNA sequencing. Results: There was no significant differences in genotype (p = 0.53) and allele (p = 0.32) distributions between ACS patient and without ACS patients groups on IL-6 allelic polymorphism and between the three different TIMI risk score (p > 0.05). Moreover IL-6 polymorphism did not affect the cytokine levels and these levels were not related to the TIMI score. Conclusions: With these results, we suggest that the IL-6 (-174 G/C) polymorphism, until now, is not related to ACS and did not change the levels of the cytokine in studied population. Further studies with different populations should be done to verify those results. It is important to emphasize that, since ACS is a multifactorial disease, other risk factors and other pro-inflammatory cytokines should be assessed to better understand this pathology

Escherichia coli as a model system to study DNA repair genes of eukaryotic organisms.

The bacteria Escherichia coli has been widely employed in studies of eukaryotic DNA repair genes. Several eukaryotic genes have been cloned by functional complementation of mutant lineages of E. coli. We examined the similarities and differences among bacterial and eukaryotic DNA repair systems. Based on these data, we examined tools used for gene cloning and functional studies of DNA repair in eukaryotes, using this bacterial system as a model.