Figure 2. Type 2 innate lymphoid cells are rare in the MLN during the early stages of Hp infection but can be induced by exogenous rIL-25 treatment. C57BL/6 mice were infected with 200 Hp L3 and Mesenteric Lymph Node (MLN) derived lymphocytes isolated and stained for a population resembling type 2 innate lymphoid cells via flow cytometry. A) Total numbers of type 2 innate lymphoid cells were quantified at day 6 post infection (p.i.) in the MLN of WT (black bars) and mast cell deficient Kit^W/Kit^W-v mice (white bars) following Hp infection alone or Hp infection with rIL-25 treatment (0.4μg i.p. on days 0–4 p.i.). B) Cells were gated as low/negative for a lineage cocktail (CD3/CD4/CD19/CD11b/CD11c) (shaded gate) and expressed the surface markers ST-2 (IL-33R), CD127 (IL-7Rα), ICOS and were c-kit low/int. C) Expression of IL-13 in Lineage low/negative gated ST-2+ or ST-2- populations in Hp infected, rIL-25 treated mice. Data are representative of two independent experiments with n = 4–6 mice per group.