Recognition of TcCA-2 epitopes by HLA-A*02:01 Chagas disease patients.

K562-A2 cells were pulsed with 1 mM of each peptide for 1 h, and co-cultured with PBMCs from asymptomatic HLA-A*02:01 Chagas disease patients. Following 30 h of growth, IFN-γ secretion was measured in the supernatants. IFN-γ secretion level in K652 cells, not expressing the class I molecule, was subtracted from the values obtained in the assays with the K562-A2 cells loaded with peptides. Responses were considered positive when the supernatant IFN-γ concentration of the peptide-stimulated cells was at least two folds the concentration of the un-stimulated cells (non-peptide). a Patients with positive response, in relation with the total number of patients per assay. b Range of IFN-γ secretion by patients with a positive response to TcCA-2 peptides. Recognition of TcCA-2 epitopes by HLA-A*02:01 Chagas disease patients.