Immune suppression or enhancement by CD137 T cell costimulation during acute viral infection is time dependent
J. Clin. Invest. Benyue Zhang, et al. 117:3029 doi:10.1172/JCI32426 [Go to this article.]

Figure 7
IL-10 and T cell deletion. (A) Serum IL-10 levels in LCMV Armstrong–infected mice treated with anti-CD137 (solid line) or rat IgG (dotted line) were measured by ELISA over the 8-day course of the infection. Staggered groups (n = 5) of mice were bled (100 μl whole blood) twice on overlapping days to avoid stressing the mice. The data are typical of 3 experiments. (B) Groups of 5 mice were infected with LCMV Armstrong and injected the following day with anti-CD137 or rat IgG. On days 4 and 8 P.I., the mice were euthanized and the frequencies of preapoptotic, apoptotic, and necrotic splenic CD4⁺ and CD8⁺ T cells determined by 7AAD and Annexin V staining. The sum of the frequencies of dead and dying cells consisted of the frequencies of cells falling in the 2 right quadrants + the upper left quadrant of each of the 4 contour plots shown, and their sums are shown in the cross-hair figure under each of the 2 sets of contour plots. (C) CD4⁺ T cell loss is absent in LCMV Armstrong–infected anti-CD137–injected IL-10–deficient mice. Mice were infected with LCMV and injected with anti-CD137 or rat IgG as described above. The number of CD44^hiCD62L^lo/– CD4⁺ splenic T cells was measured by FACS on day 8 P.I.