Perfil de citocinas no soro de pacientes com dengue em um instituto de referência em Manaus

Abstract

Dengue disease is a serious public health problem in Brazil. There are four serotypes, DENV 1 to 4. In Brazil, all serotypes are circulating and are able to cause disease to humans, and may progress to a severe level, including death. Dengue transmission occurs by the bite of the female mosquito Aedes aegypti, widely distributed in tropical and subtropical countries. Brazil underwent a major epidemic in 1955 after which the disease was considered eradicated, causing disinterest among the medical community. The objective of this project was to trace the profile of cytokines in serum from patients with dengue in the city of Manaus. The immune response to dengue virus (DENV) and their serotypes has not yet been fully elucidated. Recently, studies demonstrated increased proinflammatory cytokines in patients infected with DENV-2, as IFN-γ, IL-6 and IL-17. However, the role of cytokines in the immune reponse Th1, Th2 and Th17 in dengue disease is still poorly understood. Tropical countries such as Brazil are conducive to a proliferation of vectors making it necessary to investigate the cytokine profile in the serum of patients with dengue, especially in a locality like Manaus. This study was a retrospective cross-sectional analytical component with cases of patients seen during the dengue epidemic in the Tropical Medicine Foundation of Amazonas Dr. Heitor Vieira Dourado (FMT / HVD) in the period of January to December 2011, as well as negative controls from the Foundation of Hematology and Hemotherapy of the State of Amazonas (FHEMOAM). There were 90 serum samples, 60 from patients with dengue and 30 control patients divided into: Group I: negative control - blood donors (n = 30), Group II: positive control - DENGUE NOT SEVERE (n = 30) and Group III: positive control DENGUE SEVERE (n = 30). The diagnosis was made by viral protein NS1, dengue IgM serology, and finally the RT-PCR. The project was approved by the Ethics Committee of the Universidade do Amazonas (UFAM), n. 256-163 - CONEP. The dosages of IL-2, IL-4, IL-6, IL-10, TNF-α, IFN-γ and IL17A were performed by flow cytometry (BD CBA Kit ® Biosciences). We used the nonparametric Kruskal-Wallis (P<0,05). The graphics were designed using Graphprisma ® software. In all quantified cytokines (IL-2, IL-4, IL-6, IL-10, IFN-γ and IL-17A and TNF-α) it was possible to evaluate that in dengue groups (severe and non-severe) they had concentrations increased and statistically significant when compared to the negative control group. There was no difference in these cytokines when comparing the severe and not severe groups. Observing the behavior of cytokine IL-10, there was a trend in increase when comparing patients from dengue group who progressed to severe dengue. This pioneer study in this field in the northern region enabled us to identify the profile of a group of cytokines and infer their involvement in the immune response in circulating serotypes in Manaus in 2011.