Neuroimmunological studies of experimental Chagas\' disease. Histomolecular analysis of the spinal cord of immunecompetent and immunedeficient mice that have been infected with parasites of Sylvio X10/4 strain of Trypanosoma cruzi.

Author(s)

André Luis Bombeiro

• Document type: Doctoral Thesis
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Instituto de Ciências Biomédicas (ICB/SDI)
• Defense date: 2011-08-05

Examining board members

Jose Maria Alvarez Mosig; Alexandre Salgado Basso; Silvia Beatriz Boscardin; Niels Olsen Saraiva Câmara; Leonilda Maria Barbosa dos Santos

• Advisor: Jose Maria Alvarez Mosig; Gerson Chadi

Abstract

The establishment of a TH1 response with IL-12, IFN-gamma and nitric oxide production is crucial for controlling the proliferation of Trypanosoma cruzi, which may colonize the CNS of children and immunosuppressed hosts. The exacerbated inflammation due to the persistence of an antigenic stimulus results on the accumulation of potentially cytotoxic substances, such as pro-inflammatory mediators and free radicals. By the infection of immunodeficient mice (IL-12p40KO) with T. cruzi Sylvio X10/4 parasites we evaluated the spinal cord damages, focusing on the inflammation and neurodegeneration. Besides demyelization, high glial reactivity and neuron death at the latest stage of the disease, we noticed low production of inflammatory mediators during the first weeks of the infection, accompanied by an ascendant parasite proliferation in the nervous tissue. We believe that a delay on IFN-gamma production is responsible for the late or inefficient phagocyte activation in the spinal cord, contributing to the uncontrolled protozoan proliferation and subsequent tissue injury. (AU)