title: The role of interleukin 17-mediated immune response in Chagas disease: High level is correlated with better left ventricular function.
abstract: Interleukin 17A (IL-17A) has been associated with protective rather than pathogenic response in Chagas disease (ChD). However, it is not established whether or not IL-17A-mediated immune response is correlated with patient's left ventricular (LV) function in ChD. To address this question we have gathered cardiac functional parameters from ChD patients and analysed the possible relationship between their plasma IL-17A levels and LV function. Plasma IL-17A levels were measured by BD Cytometric Bead Array (CBA) in 240 patients with positive specific serology for Trypanosoma cruzi (T. cruzi) grouped as indeterminate (IND) and Chagas cardiomyopathy (CARD) forms. The levels of IL-17A in ChD patients were compared with 32 healthy individuals, mean age of 39 years, 50% male, that were also included as a control group (non-infected [NI]). The overall mean age of ChD patients was 46 years and 52% were male. The IND group included 95 asymptomatic patients, with ages ranging from 27 to 69 years (mean of 43 years), and 42.1% of them were male. The CARD group included 145 patients, which 58.6% were male, with ages ranging from 23 to 67 years (mean of 49). The IND group presented substantially higher levels of IL-17A, median of 26.16 (3.66-48.33) as compared to both the CARD group, median of 13.89 (3.87-34.54) (P <0.0001), and the NI group, median of 10.78 (6.23-22.26) (P <0.0001). The data analysis demonstrated that the IND group comprises a significantly greater proportion (P <0.001) of high IL-17A producers (52.6%, 50 of 95 subjects) than do the other groups. A significant direct correlation was verified between IL-17A levels and cardiac function expressed by LV ejection fraction (LVEF), LV diastolic diameter (LVDd), and body surface area (BSA)-indexed LVDd as well as ratio of the early diastolic transmitral flow velocity to early diastolic mitral annular velocity (E/e') in both groups. We demonstrated that plasma IL-17A levels has an accurate sensitivity and specificity to predict heart failure in serology-positive patients and might be a useful parameter to distinguish patients with or without cardiac impairment. This study indicates a consistent relationship between high expression of IL-17A and better LV in human chronic ChD. Our data raise the possibility that IL-17A plays an important immunomodulatory role in the chronic phase of ChD and might be involved in protection against myocardial damage.
authors.affiliation: Postgraduate Course of Infectious Diseases and Tropical Medicine, School of Medicine, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
authors.forename: Giovane R
authors.identifier: http://orcid.org/0000-0003-0085-3882
authors.initials: GR
authors.lastname: Sousa
authors.affiliation: Postgraduate Course of Infectious Diseases and Tropical Medicine, School of Medicine, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.|Laboratory of Cell-Cell Interactions, Department of Morphology, Institute of Biological Sciences, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
authors.forename: Juliana A S
authors.initials: JA
authors.lastname: Gomes
authors.affiliation: Laboratory of Cell-Cell Interactions, Department of Morphology, Institute of Biological Sciences, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
authors.forename: Marcos Paulo S
authors.initials: MP
authors.lastname: Damasio
authors.affiliation: Postgraduate Course of Infectious Diseases and Tropical Medicine, School of Medicine, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
authors.forename: Maria Carmo P
authors.initials: MC
authors.lastname: Nunes
authors.affiliation: Postgraduate Course of Infectious Diseases and Tropical Medicine, School of Medicine, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
authors.forename: Henrique S
authors.initials: HS
authors.lastname: Costa
authors.affiliation: Laboratory of Cellular and Molecular Immunology, Centro de Pesquisas René Rachou, FIOCRUZ, Belo Horizonte, MG, Brazil.
authors.forename: Nayara I
authors.initials: NI
authors.lastname: Medeiros
authors.affiliation: Laboratory of Cellular and Molecular Immunology, Centro de Pesquisas René Rachou, FIOCRUZ, Belo Horizonte, MG, Brazil.
authors.forename: Rafaelle C G
authors.initials: RC
authors.lastname: Fares
authors.affiliation: Postgraduate Course of Infectious Diseases and Tropical Medicine, School of Medicine, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
authors.forename: Ana Thereza
authors.initials: AT
authors.lastname: Chaves
authors.affiliation: Laboratory of Cellular and Molecular Immunology, Centro de Pesquisas René Rachou, FIOCRUZ, Belo Horizonte, MG, Brazil.|National Institutes of Science and Technology Tropical Diseases (INCT-DT), Belo Horizonte, MG, Brazil.
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Corrêa-Oliveira
authors.affiliation: Postgraduate Course of Infectious Diseases and Tropical Medicine, School of Medicine, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
authors.forename: Manoel Otávio C
authors.initials: MO
authors.lastname: Rocha
mesh_terms: D000328:Adult; D000368:Aged; D019540:Area Under Curve; D016022:Case-Control Studies; D002598:Chagas Cardiomyopathy / Q000175:diagnosis / Q000276:immunology / Q000469:parasitology; D014355:Chagas Disease / Q000175:diagnosis* / Q000276:immunology* / Q000469:parasitology; D004452:Echocardiography; D005260:Female; D006801:Humans; D007118:Immunoassay; D020381:Interleukin-17 / Q000097:blood* / Q000276:immunology*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D012372:ROC Curve; D006377:T-Lymphocytes, Helper-Inducer / Q000166:cytology / Q000276:immunology / Q000378:metabolism; D014349:Trypanosoma cruzi / Q000302:isolation & purification; D016277:Ventricular Function, Left / Q000502:physiology*
chemical_list: D020381:Interleukin-17