“…Based on our data, we are very tempted to suggest that the quality of the Th1 response induced by L. amazonensis antigens, involving a poor generation of multifunctional CD4 + T cells and a high proportion of IFN‐γ single‐positive CD4 + T cells, in association with its well‐known capacity of inducing IL‐10 production [45–47,51,53,54], can be involved in the mechanisms responsible for the susceptibility to L. amazonensis observed in ATL patients and in experimental models. In this sense we have shown, for the first time, that multiparametric flow cytometry can bring new important aspects to the studies of ATL immunopathogenesis, and reinforce the importance of evaluating not just the magnitude, but the quality of a pathogen‐specific Th1 immune response by multiple parameters at a single‐cell level, to find better and more effective biomarkers of disease and protection.…”