Figure 9

Frequencies of regulatory T-cell populations. The percentages of CD25⁺Foxp3⁺ cells in the CD4⁺CD8⁻ T lymphocyte populations in PBMC, BLN, BAL and lung parenchyma single-cell suspensions were enumerated by flow cytometry. The frequency of the Treg subpopulations in the negative control and infected pigs at each time point during the course of infection is presented in the graphs. The data represent the mean ± SEM for each population, and the asterisk (*) indicates a statistically significant difference between the averages found for the negative control (NC) pigs and those obtained for the challenged pigs at each time point (* indicates p ≤ 0.05 and ** indicates p ≤ 0.01).