Fig. 1

Application route dependent effects of VacA on the asthma phenotypes. a) On day 0 all animals were sensitized intranasally (i.n.) with 1 µg house dust mite (HDM); on day 7–11, the positive control and the three different VacA-treated groups were challenged i.n. with 10 µg HDM. The negative control group was challenged with phosphate-buffered saline (PBS). On days 6, 7, 9 and 11, animals were treated 20 µg VacA given via the intraperitoneal (i.p.), oral (p.o.) or intratracheal (i.t.) route. b) Cellular composition of bronchoalveolar lavage (BAL): total cell count (Tcc), macrophages, lymphocytes, neutrophils and eosinophils. c) Lung tissue inflammation: representative sections of each indicated group are shown (x100); scatter plot of inflammation score. d) Mucus-producing cells: pictures show representative sections from each group (x200); scatter plot of the number of mucus producing cells per mm of basement membrane. e) VacA treatment increases proportions of Tregs. Tregs were characterized by the expression of FoxP3⁺ CD25⁺ cells in the CD3⁺ CD4⁺ cell population; box plots show the percentage in lung, spleen, tracheal lymph node (tLN) and mesenteric lymph node (mLN); results from six independent experiments n = 6–15 per group. n.s. not significant; *p < 0.05; **p < 0.01; ***p < 0.001; ****p < 0.0001