FIG 4.

Mean fluorescence intensities (MFI) of expression of activation markers on lymphocyte populations of CD4⁺ (A), CD8⁺ (B), and γδ TCR⁺ (C) T cells within total PBMCs isolated from control noninfected cows and cows in subclinical and clinical stages of disease. Cells were stimulated in vitro for 6 days with a whole-cell sonicate of Mycobacterium avium subsp. paratuberculosis (MPS). Mononuclear cells, based on forward- and side-scatter characteristics, were analyzed for cell surface marker expression. Activation markers expressed on CD4, CD8, and γδ TCR⁺ T cell subsets are expressed as MFI. Data are expressed as means ± SEM (*, P < 0.01; **, P < 0.05).