To determine whether there were differences in expansion of Tregs following T. congolense infection, we sacrificed infected mice at days 0 (no infection), 2, 4, 6 and 8 post-infection and determined the total number of cells, the percentages and absolute numbers of CD4+CD25+FoxP3+ cells in the spleens directly ex vivo by flow cytometry. Here, FOXP3 is linked to infection.