Expression of PD-L1 by infiltrating leukocytes in a chronically infected heart. C3H/HePAS mice were infected with 4 × 105 Sylvio X10/4 trypomastigotes obtained from LLCMK2 cultures. At day 400 postinfection, mice were sacrificed, and the heart tissue was digested with collagenase to isolate the infiltrating leukocytes. PD-L1 expression was analyzed by flow cytometry. Heart leukocytes from a pool of age-matched noninfected mice were also included.
