Immunological response to re-infections with clones of the Colombian strain of Trypanosoma cruzi with different degrees of virulence: influence on pathological features during chronic infection in mice

Abstract

Re-infections with Trypanosoma cruzi are an aggravating factor for Chagas disease morbidity. The Colombian strain of T. cruzi represents multiclonal populations formed by clonally propagating organisms with different tropisms and degrees of virulence. In the present study, the influence of successive inoculations with clones of the Colombian strain, exhibiting different degrees of virulence, on chronic myocarditis and the humoral and cellular immune responses (Col-C1 high virulence, Col-C8 medium virulence and Col-C5 low virulence) were demonstrated. Mice from three groups with a single infection were evaluated during the acute (14th-30th day) and chronic phases for 175 days. An immunofluorescence assay, ELISA and delayed type hypersensitivity (DTH) cutaneous test were also performed. Mice with a triple infection were studied on the 115th-175th days following first inoculation. The levels of IgM and IgG2a were higher in the animals with a triple infection. DTH showed a higher intensity in the inflammatory infiltrate based on the morphometric analysis during a 48 h period of the triple infection and at 24 h with a single infection. The histopathology of the heart demonstrated significant exacerbation of cardiac inflammatory lesions confirmed by the morphometric test. The humoral responses indicate a reaction to the triple infection, even with clones of the same strain.

Treatment with Fenofibrate plus a low dose of Benznidazole attenuates cardiac dysfunction in experimental Chagas disease

“…This allowed us to design a mixed infection model that, both in terms of cardiac dysfunction as well as in its pathophysiological consequences, resembles what happens in chronic Chagas disease patients. In support of this, previous studies have shown that multiple infections lead to worsening of the inflammatory reaction ( Bustamante et al, 2002 , Bustamante et al, 2003 , Bustamante et al, 2004 , Andrade et al, 2006 ) and immunopathological ( Guerreiro et al, 2015 ) consequences.…”

Scientometrics analysis of research activity and collaboration patterns in Chagas cardiomyopathy

“…Our findings revealed a high degree of domestic collaboration, especially in recent years, in response to the multidisciplinary nature of this clinical entity, which is relevant to tropical medicine, parasitology, cardiology, pathology, biochemistry and immunology, infectious diseases, physiology, microbiology and public health [ 25 – 26 ].…”

Congenital Chagas disease as an ecological model of interactions between Trypanosoma cruzi parasites, pregnant women, placenta and fetuses

“…This might stimulate finally the development of congenital-infection and -Chagas disease and jeopardize the fetus/neonate life. Interestingly, experimental data also highlight the pejorative role of re-infections in chronically infected animals, as well as in gestating dams which strongly increase pup mortality (Bustamante et al, 2002;Cencig et al, 2013;Guerreiro et al, 2015). This concept of an ecological interaction between repeated vector transmissions of parasites during pregnancy and a non-vector transmission in offspring might have practical consequences, since vector control programs in endemic Latin American areas might contribute to limit the severity of congenital Chagas disease.…”