Figure 7.

Inhibition of activation-induced T-cell death shifts M2 into M1 macrophages. (a) PECs from T. cruzi-infected mice were cultured with or without plate-bound anti-CD3 in the presence of caspase inhibitor zVAD or dimethyl sulfoxide (DMSO). Cells were detached after 48 h for evaluation of MGL1 and IL-12p35 expression in gated F4/80⁺ cells. NO production was measured in 48 h culture supernatants. Results are expressed as means and S.E.M. of three to four technical replicates of pooled PECs from infected mice. (b) T cells from normal or infected mice (20 dpi) were treated with anti-CD3 in the absence or presence of zVAD or DMSO during 4 h for in vivo injection and 24 h (c) for flow cytometry. (c) T cells were analyzed for annexin V staining in CD8 and CD4 T cells. Results are expressed as means and S.E.M. of four to five technical replicates. (d and e) Infected mice (20 dpi) were injected intraperitoneally with phosphate-buffered saline (PBS) (−) or with 2 × 10⁶ activated T cells (treated with zVAD or DMSO). After 2 days, PECs were collected and activated with PMA and ionomycin, before staining for MGL1 and IL-12p35 expression in F4/80⁺ cells. (e) Symbols represent PECs from individual infected mice treated with PBS (Δ) or with T cells (▾) activated in the presence of zVAD or DMSO (N=4 mice per group). Significant differences between treatments are indicated (*), as analyzed by t-test (a and c) or by analysis of variance (ANOVA) with Tukey's post-test (e)