Effect of <i>T. cruzi</i> infection on MHC class I cell surface expression.

<p>(A) Immunofluorescence microscopy of HeLa cells treated with IFN-γ and/or <i>T. cruzi</i>-infected stained with human anti-MHC class I antibody (yellow) and DAPI (blue). The arrows highlight the infected cells that clearly had the MHC class I expression down-modulated by <i>T. cruzi</i> infection. Bars = 25 µm. To precisely quantify the MHC class I cell surface expression, samples used in microscopy were analyzed by flow cytometry. (B) The protein expression was determined as median fluorescence intensity (MFI). Each value represents the mean ± standard deviation of three independent experiments.