CD4 and cyst: However, i.v. or i.p. inoculation with 107 tachyzoites led to secretion of IFN-γ by CD3+CD8+, CD3+CD4–CD8– (DN) T cells and CD3–NKp46+ cells in spleen, MLN and PP as early as 2–24 h after inoculation (Fig. 1c,d, g, h; Fig. S1c,d), mirroring the results seen 5 days after a cyst inoculation (Fig. 1b,f).