Cytokines profile and its relation with parasitemia in cattle experimentally infected by Trypanosoma vivax

Author(s)

Otavio Luiz Fidelis Junior

• Document type: Doctoral Thesis
• Press: Jaboticabal. 2018-01-17.
• Institution: Universidade Estadual Paulista (Unesp). Faculdade de Ciências Agrárias e Veterinárias. Jaboticabal
• Defense date: 2017-11-06
• Advisor: Fabiano Antonio Cadioli; Marcos Rogério André

Abstract

Trypanosoma vivax outbreaks have been occurring with increasing frequency in Brazilian herds, although the Brazilian Ministry of Agriculture, Livestock and Supply (MAPA) does not consider this disease a problem, there is no official control or accurate records of its occurrence. T. vivax causes great damage to the livestock where it occurs. Establish the disease diagnosis is a challenging task, since many clinical, immunological and laboratory aspects are not completely elucidated. In the present study were evaluated several techniques for T. vivax diagnosis in order to verify the best way of using them during the course of the disease. It was also to evaluate the cytokine profile (IL-1β, IL-2, IL-4, IL-6, IL-10, IL-12, TNFα and IFNγ) associated with the parasitemia in three Girolando cows (E1 to E3) experimentally infected with 2.0 x 107 trypomastigotes of T. vivax, isolate "Lins". Blood samples obtained seven days before inoculation (D-7), on the day of inoculation (D0), the day after inoculation (D1) and then every seven days up to 119 days after infection (DAI) were used. Molecular methods showed higher detection rates (61.1%), while the best parasitological test detected only 44.4%. The serological methods, RIFI and ELISA, detected seropositivity in 94.4% and 90.7% of the samples known to be positive, respectively. The analyses revealed that the acute phase of the disease may extend up to 42 days after infection (DAI), longer than previously reported. The cytokine profile presented by cattle, during the course of the infection, presented an individual pattern and no correlation was found between the expression and the plasmatic concentration. Th1 response was verified during the acute phase of the disease and, at the beginning of the chronic phase, an increase of Th2 cytokines was detected. The results obtained will help in understanding the pathophysiology of illness caused by T. vivax and may contribute to a refinement of the disease diagnosis. (AU)

• FAPESP's process: 14/10572-4 - Cytokines profile and its relation with parasitemia in cattle experimentally infected by Trypanosoma vivax
• Grantee: Otávio Luiz Fidelis Júnior
• Support Opportunities: Scholarships in Brazil - Doctorate