ACTIVATION – INDUCED MARKER ASSAY, AN ALTERNATIVE STRATEGY TO STUDY TRYPANOSOMA CRUZI SPECIFIC CD8+ T CELLS

BISCARI, LUCÍA; KAUFMAN, CINTIA DANIELA; FARRÉ CECILIA; HUHN, VICTORIA; PÉREZ, ANA ROSA; ALLOATTI, ANDRÉS

Congreso; REUNIÓN DE SOCIEDADES DE BIOCIENCIAS 2021; 2021

SOCIEDAD ARGENTINA DE INMUNOLOGÍA

In the investigation of the immune response induced by vaccinesor generated against infectious diseases, the determination of thespecific CD8 response is of particular importance. Although thereare various techniques for this purpose, such as the use of specifictetramers or ELISPOT, the activation – induced marker (AIM) technique emerges as a simpler experimental approach. In this work, wetested and optimized AIM to analyze the response of CD8+ T cellsspecific for Trypanosoma cruzi antigens, generated after infectionof C57BL/6 mice with the Tulahuén strain of T. cruzi. Animals wereinfected intraperitoneally with 5000 T. cruzi trypomastigotes. At 12days post infection, at the peak of the CD8+ T response, the animalswere sacrificed and spleens and lymph nodes were harvested. Splenocytes and lymph node cells were incubated for 15 h with differentconcentrations of a particular peptide (TsKb20, derived from theTransialidase protein or PAR4, derived from the PAR4 protein of theflagellum, from T. cruzi). Cells incubated with Concanavalin A wereused as a positive control, and non-restimulated cells were used asa negative control. The specific CD8 response was determined byflow cytometry evaluating the activation markers CD25+ and CD69+in the population of CD8+ T cells. Through a two-way ANOVA analysis, it was found that the specific CD8+ T cell response for TsKb20in infected animals, measured after restimulation with 50 ug/mLof the TsKb20 peptide, was significantly higher than the responsemeasured in uninfected animals. No difference was evidenced inthe specific CD8 response for PAR4. These results suggest that theAIM technique could be used to determine anti-T. cruzi specific CD8response.