P23 - Parasitología

Extracellular Vesicles from PBMC of patients infected with T. cruzi: Characterization in the search for biomarkers

Alvarado Andres¹ - Buonincontro Brenda¹ - Principato Mario² - Carvelli María Victoria² - Bertho Álvaro Luiz³ - Ramírez Marcel⁴ - Carbajales Justo² - Poncini Carolina¹

1) Instituto de Investigaciones en Microbiología y Parasitología Médica (IMPaM), UBA-CONICET, Ciudad Autónoma de Buenos Aires, Argentina.
2) División de Cardiología, Hospital General de Agudos J. M. Ramos Mejía, Ciudad Autónoma de Buenos Aires, Argentina.
3) Laboratorio de Inmunoparasitología, Instituto Oswaldo Cruz, Rio de Janeiro, Brasil.
4) Laboratorio de Biología Celular, Fundación Carlos Chagas, Instituto Oswaldo Cruz PR, Curitiba, Brasil.
Contacto: annerdross_133@hotmail.com

Chagas disease (CD), caused by the protozoan Trypanosoma cruzi (T. cruzi) represents a major public health problem in Latin America. Late diagnosis, incomplete treatment, or inadequate follow-up can make the infection potentially fatal (WHO). Early detection, a deeper understanding of the pathogenesis, and the development of new treatments would reduce morbidity and mortality. In the following study, we aimed to characterize the release of extracellular vesicles (EVs) from peripheral blood mononuclear cells (PBMCs) of asymptomatic patients (A), with alterations in cardiac electrical conduction (B), and with dilated cardiomyopathy (C), as well as individuals not infected with T. cruzi (N). The overall goal is the identification of prognostic biomarkers for CD. The method used to obtain EVs included high-speed centrifugation, thus achieving independence from the use of ultracentrifugation. We recovered EVs with sizes comparable to those obtained by ultracentrifugation (by nanoparticle tracking, NTA, and Transmission Electron Microscopy, TEM). Using TEM, we observed that high-speed centrifugation yielded clearer EVs free of protein complexes. Furthermore, we observed an increase in EV release in the presence of parasite stimulation in patient PBMCs, by NTA. Two patterns of EV release were detected in patients A, which could be interpreted as a possible differential state of cellular activation. EV detection by EV nano-flow cytometry was also developed with the aim of using this methodology in the study of biomarkers and their identification from biological samples. We propose further characterization of these EVs to identify potential diagnostic/prognostic biomarkers for the disease.

Palabras clave: Keywords: TRYPANOSOMA CRUZI, CCHAGAS DISEASE, PROGNOSTIC BIOMARKERS