The Significance of Discordant Serology in Chagas Disease: Enhanced T-Cell Immunity to in Serodiscordant Subjects.

Background: Subjects are considered infected with when tested positive by at least two out of three serological tests, whereas a positive result in only one of up to three tests is termed "serodiscordant" (SD). Assessment of parasite-specific T-cell responses may help discriminate the uninfected from infected individuals among SD subjects.

Methods: Peripheral blood mononuclear cells from SD and seropositive (SP) subjects, who were born in areas endemic for infection but living in Buenos Aires city, Argentina, at the time of the study, and seronegative unexposed subjects were included for analysis.

Clinical characteristics and outcome of 107 adult patients with chronic Chagas disease and parasitological cure criteria.

Background: The cure in adult patients with chronic Chagas disease and the relationship between parasitological and clinical evolution is still under debate. The aim of this study was to analyze the clinical, epidemiological and progression features of the disease in a patient population who became serologically negative either spontaneously or post-etiological treatment.

Methods: We included 107 patients over 20 years old with three different confirmed reactive anti-Trypanosoma cruzi serologic tests on admission, and a minimum of two years of follow-up.

Allopurinol reduces antigen-specific and polyclonal activation of human T cells.

Allopurinol is the most popular commercially available xanthine oxidase inhibitor and it is widely used for treatment of symptomatic hyperuricaemia, or gout. Although, several anti-inflammatory actions of allopurinol have been demonstrated in vivo and in vitro, there have been few studies on the action of allopurinol on T cells. In the current study, we have assessed the effect of allopurinol on antigen-specific and mitogen-driven activation and cytokine production in human T cells.

Trypanosoma cruzi DNA in cardiac lesions of Argentinean patients with end-stage chronic chagas heart disease.

The extent of inflammation, fibrosis, and progression of chronic Chagas heart disease (cChHD) was associated with persistence of parasite DNA in cardiac lesions of necropsies or explants from Argentinean cChHD patients. A Trypanosoma cruzi-based polymerase chain reaction showed a positive result in 1) 15% of cardiac sections with less than 10 mononuclear inflammatory cells/high-power field (440x) (MNC/HPF), 89% with 10-19 MNC/HPF, and 100% with more than 20 MNC/HPF (P < 0.0001); 2) 33% with less than 10% fibrosis, 79% with 10-19% fibrosis, and 100% with more than 20% fibrosis (P < 0.

Frequency of interferon- gamma -producing T cells specific for Trypanosoma cruzi inversely correlates with disease severity in chronic human Chagas disease.

This study sought to quantify CD8(+) T cell responses to Trypanosoma cruzi and to identify potential links between these responses and the severity of disease in humans. In the majority of patients with Chagas disease, staining with class I major histocompatibility complex tetramers and analysis of interferon (IFN)- gamma ELISPOT responses to a panel of known cytotoxic T lymphocyte target epitopes from T. cruzi failed to identify parasite-specific CD8(+) T cells.