Figure 3.
Antigen-specific CD4 T cell expression of CXCR5 during a primary immune response. (A) Representative probability contours for CD44 and CXCR5 expression on Vα11Vβ3-expressing T cells over the course of a primary response. All profiles are presented as 5% probability contours with outliers, and are propidium iodide− CD8−B220−CD11b−Vα11+Vβ3+. The day after antigen administration is displayed above each panel. The quadrants are defined by the horizontal dotted lines, and indicate the limits of CD44 and CXCR5 regulation that were used to calculate the frequencies of cellular subsets. (B) Frequencies of Vα11Vβ3-expressing T cells that have upregulated CD44 and are either CXCR5− (left panel) or CXCR5+ (right panel). (C) The total number of antigen-activated Vα11Vβ3-expressing T cells in the draining LNs as calculated using the frequencies obtained by flow cytometry and total cell counts estimated when organs were harvested; the left panel represents the CXCR5− subset, the right panel represents the CXCR5+ subset. Each estimation (B and C) is presented as the mean from at least three separate animals ± SEM.