Defect in antigen-induced NHR in antigen-specific IgE-Tg mice.

<p>IgE-Tg mice as well as antigen-immunized mice and T cell-transferred mice were challenged 3–4 times with OVA or saline, as shown in Figs <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0146686#pone.0146686.g002" target="_blank">2</a> and <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0146686#pone.0146686.g006" target="_blank">6</a>. Six hours after the 3rd challenge, antigen-specific serum IgE, IgG, IgG₁, IgG_2a, IgG_2b, and IgG₃ were determined (A). The number of sneezes evoked by histamine (B) and accumulation of lymphocytes, neutrophils, and eosinophils in NALF (C) of IgE-Tg mice were examined 6 h after the 4th challenge. Data are expressed as mean ± SEM for 4–8 animals. *<i>p</i> < 0.05, **<i>p</i> < 0.01 (Dunn’s test). N.D.: not detectable.</p

Antigen-induced NHR in T cell-transferred mice.

<p>Twenty-four hours after transfer of Th1, Th2, or Th17-polarized cells, mice were challenged 3 times with OVA or saline. Six hours after the last challenge, the number of sneezes evoked by histamine (A), the accumulation of lymphocytes, neutrophils, and eosinophils in NALF (B), and the IFN-γ, IL-4, and IL-17 mRNA expression in the nasal tissue (C) were examined. Data are expressed as mean ± SEM for 4–8 animals. *<i>p</i> < 0.05, **<i>p</i> < 0.01, ***<i>p</i> < 0.001, compared with naïve T cell-transferred and OVA-challenged mice (Dunn’s test). N.D.: not detectable.</p

Effect of anti-CD4 mAb on antigen-induced NHR.

<p>Immunized mice were challenged 4 times with OVA or saline, as shown in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0146686#pone.0146686.g002" target="_blank">Fig 2</a>. Anti-CD4 mAb or control rat IgG was administered twice, that is, at 9 and 6 days before the last challenge. Six hours after the last challenge, the CD3⁺CD4⁺ population in the spleen was determined by flow cytometry (A). Representative data from 3 independent experiments are shown. The number of sneezes evoked by histamine (B) and the accumulation of lymphocytes, neutrophils, and eosinophils in NALF (C) were also examined. Data are expressed as mean ± SEM for 4–6 animals. *<i>p</i> < 0.05, **<i>p</i> < 0.01, ***<i>p</i> < 0.01, compared with OVA-challenged control mice (Dunn’s test).</p

Antigen-induced NHR in immunized mice.

<p>Mice were immunized with 4-time i.p. injection of OVA plus alum. Two weeks after the last immunization, mice were challenged once a day with daily i.n. injection of OVA or BSA solution, or of saline on days 35–38 and 41–43. Then, these mice were challenged with OVA, BSA, or saline on day 44 (A). On days 41–44, the number of sneezes was counted for 5 min just after i.n. administration of OVA, BSA, or saline (B). The BSA- and histamine-evoked sneezing response was evaluated at 6 h after 0 (day 34)- to 4 (day 38)-time challenge with OVA or saline (C). Time course of histamine-evoked sneezing response after 4-time challenge on days 35–38 with OVA or saline was evaluated (D). Data are expressed as mean ± SEM for 4–10 animals. *<i>p</i> < 0.05, compared with saline-challenged control mice (Mann-Whitney <i>U</i> test).</p

Antigen-induced NHR in mast cell-deficient mice.

<p>Immunized W/W^v and +/+ mice were challenged 7 times with OVA or saline, as shown in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0146686#pone.0146686.g001" target="_blank">Fig 1</a>. Six hours after the last challenge (day 43), the number of sneezes evoked by histamine (A), the accumulation of lymphocytes, neutrophils, and eosinophils in NALF (B), and the antigen-specific serum IgE levels were examined (C). Data are expressed as mean ± SEM for 4–9 animals. *<i>p</i> < 0.05, **<i>p</i> < 0.01, ***<i>p</i> < 0.001, compared with saline-challenged control mice (Mann-Whitney <i>U</i> test).</p

Antigen-induced NHR in eosinophil-deficient mice.

<p>Immunized ΔdblGATA and WT mice were challenged 7 times with OVA or saline, as shown in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0146686#pone.0146686.g001" target="_blank">Fig 1</a>. Six hours after the last challenge (day 43), the number of sneezes evoked by histamine (A), the accumulation of lymphocytes, neutrophils, and eosinophils in NALF (B), and the antigen-specific serum IgE levels were examined. Data are expressed as mean ± SEM for 4–8 animals. *<i>p</i> < 0.05, **<i>p</i> < 0.01, compared with saline-challenged control mice (Mann-Whitney <i>U</i> test). N.D.: not detectable.</p

Antigen-induced nasal inflammation in immunized mice.

<p>Immunized mice were challenged 4 times with OVA or saline on days 35–38. Six hours after the last challenge, accumulation of lymphocytes, neutrophils, and eosinophils in NALF (A) and expression of IL-4, IL-5, IL-13, IFN-γ, IL-17, and EPO mRNA in the nasal tissue (B) were examined. Data are expressed as mean ± SEM for 4–9 animals. *<i>p</i> < 0.05, **<i>p</i> < 0.01, compared with saline-challenged control mice (Mann-Whitney <i>U</i> test). Lateral nose sections were stained with hematoxylin and eosin and observed under optical microscopy. Representative images from 3 independent experiments are shown in panel C. The lower panels are enlarged views of the squares in the upper panels. White and black bars indicate 500 and 50 μm, respectively. The number of infiltrated eosinophils and the grade of epithelial damage are evaluated from the histological images (D). Data are expressed as mean ± SEM. **<i>p</i> < 0.01, compared with saline-challenged control mice (Mann-Whitney <i>U</i> test).</p

Overpotential-Induced Introduction of Oxygen Vacancy in La_0.67Sr_0.33MnO₃ Surface and Its Impact on Oxygen Reduction Reaction Catalytic Activity in Alkaline Solution

Oxygen reduction reaction (ORR) catalytic activity of La_0.67Sr_0.33MnO₃ epitaxial thin films was investigated in a KOH solution by using a rotating-disk electrode. We found that while the films exhibit ORR current, the current is not limited by oxygen transport resulting from the film electrode rotation and shows the large hysteresis against the potential sweep direction. This behavior is in stark contrast to the oxygen reduction reaction activity of an electrode ink made from LSMO bulk powder, whose ORR current is oxygen-transport limited. <i>In situ</i> synchrotron X-ray absorption spectroscopy also reveals that the valence state of Mn in the LSMO film surface is lowered under the reducing atmosphere caused by the overpotential. This indicates the overpotential-induced introduction of oxygen vacancies in the film surface. We also show that the ORR current of the LSMO films exposed to the reducing atmosphere is lowered than that of the original surface. These results indicate that the ORR catalytic activity of LSMO surfaces is strongly influenced by oxygen vacancies