FOXP3 and infection: Additionally, the mean fluorescence intensity of the three surface markers was significantly augmented among Foxp3+ cells after infection, as shown in Fig 5B Simultaneously, the proportion of Foxp3− cells within the CD4+CD25+ compartment decreased, suggesting a loss of the most closely tTreg precursors (CD4+CD25+Foxp3− cells) during infection (Fig 5C).