Effector Memory Th1 CD4 T Cells Are Maintained in a Mouse Model of Chronic Malaria
Figure 2
Effector CD4+ T cells persist in P. chabaudi infection and early effector memory cells predominate.
Naïve (CD44loCD25−), CFSE-labelled B5 T cells (2×106) were seeded into congenic Thy1.1+ mice, which were then infected with 105 P. chabaudi iRBC. A) Divided B5 cells (CFSEneg) were analyzed for expression of CD62L and IL-7Rα to measure the percentages of Teff (CD62Llo, IL-7Rα−) in the spleen on day 9 (middle panel) and day 60 (right panel). As an internal negative control, naïve cells (CFSE+) from uninfected mice are shown (left panel). B) CD44hiIL-7Rα+ memory cells are shown in the divided CFSEneg population. C) Kinetics of appearance of Teff and Tmem as defined in A) and B) by percentage (left panel) or number (×103, right panel). D) Tmem were subdivided using CD62L and CD27 to measure central (Tcm, CD62LhiCD27+), and early effector memory cells (TemE, CD62LloCD27+) as well as CD27− late effector memory T cells (TemL, CD62LloCD27−) shown here at day 60 of infection. The relative proportions of Tcm, TemE and TemL of infection are shown in the right graph. E) PD-1 expression on B5 Transgenic CD4+ T cells seeded in Thy1.1 congenic mice at different times during P. chabaudi infection. All PD-1+ cells were CD62Llo. Graphs represent the means and SEM of 2 to 5 mice per time point. Plots show CD4+Thy1.2+CFSEneg cells concatenated from 2–5 mice per time point (gated as shown in Figure 1A, raw data for B, D shown in Figure S3). Experiments were repeated three times with similar results.