Figure 7. Gr1^int and Gr1^hi cells sorted from M. tuberculosis infected NOS-/- mice activate Th17 cells and induce proliferation of CD4⁺ T cells.

Specific populations of Gr1^int or Gr1^hi cells were sorted from infected NOS-/- mice and placed into in vitro cultures with increasing numbers of either stimulated naïve or infected splenocytes. After 2 days of incubation T cells were evaluated for activation and memory profiles (A-D). Panel A -D shows lower ratios of Gr1^high (A and C) or Gr1^int (B and D) induce increased the percentage of activation of CD4⁺CD69⁺IL-17⁺ and memory CD4⁺CD44⁺IL-17⁺, when co-incubated with naïve (A and B) or M. tuberculosis infected splenocytes (C and D), respectively. Panel E and F shows Gr1 ^high and Gr1^int induced of proliferating CD4 T cells. However, as the splenocyte to Gr1^high or Gr1^int ratio increased the percentage of CD4+ proliferation was reduced. Results are expressed as the mean values of mean percentage of CD4⁺CD69⁺IL-17⁺, CD4⁺CD44⁺IL-17⁺ and proliferation. ANOVA and the Tukey post-test. *p<0.05, **p<0.01, ***p<0.001.