Monolayers of Madin-Darby canine kidney cells in 12-well plates were incubated with 0.1 mL of the dilutions for 1 h, and the cells were overlaid with 1.5 mL of agar medium. The plates were maintained

in a humidified atmosphere containing 5% CO2 for 2 days, and the plaques in wells were counted. The virus titers of the lungs were expressed as the number of pfu per unit weight of lung. The left lobes of lungs were fixed in 10% neutral buffered formalin solution, sectioned, and stained with hematoxylin and eosin. Histopathological RG7204 order scores were established on the basis of the extent of the histopathological findings including hypertrophy, hyperplasia, abruption and necrosis of bronchial epithelium, infiltration of inflammatory cells in bronchial submucosa

and alveolar septa, exudation of inflammatory cells in alveolus, atelectasis, edema, and hemorrhage in the alveolus. Each histopathological finding was scored as follows: 0, normal; 1, mild; 2, moderate; and 3, severe. Histopathological scores were estimated from the average of the extent of these findings. Data are expressed as mean ± SD, and P < 0.05 indicated significant differences as https://www.selleckchem.com/products/ABT-263.html determined by Student’s t-test for comparisons between groups. A total of 85 strains consisting of 57 strains from 16 species of Lactobacillus, 14 strains from 5 species of Bifidobacterium, 8 strains from 2 species of Lactococcus, 4 strains from 2 species of Enterococcus, and 2 strains from 1 species of Streptococcus were examined for their ability to induce IL-12. Murine splenocytes were cultured with heat-killed

bacteria (1 μg mL−1) for 2 days and the levels of IL-12p70 in supernatants were determined Molecular motor (Fig. 1). Lactobacillus paracasei MoLac-1 most strongly induced IL-12. Heat-killed MoLac-1 induced IL-12p70 and IFN-γ production in a dose-dependent manner between 0.1 and 1 μg mL−1 (Fig. 2). To examine the cell types exhibiting MoLac-1-induced IL-12 production, the IL-12 production by splenocytes depleted of various cell populations was compared with that of complete splenocytes. We prepared splenocytes depleted of CD90.2+ cells (mainly T cells), B220+ cells (mainly B cells), CD11b+ cells, CD11c+ cells (mainly dendritic cells), and DX5+ cells (mainly NK cells and NKT cells). Splenocytes and the depleted splenocytes were cultured with heat-killed MoLac-1 (1 μg mL−1) for 2 days. The secretion levels of IL-12 induced by MoLac-1 were diminished in CD11b− cells but maintained in the other subsets of splenocytes depleted of CD90.2+ cells, B220+ cells, CD11c+ cells, or DX5+ cells (Fig. 3a). CD11b is expressed on macrophages/monocytes, granulocytes, NK cells and subsets of dendritic cells. Using Ly-6G, a marker expressed on granulocytes, we found that Ly-6G− cells produced IL-12 induced by MoLac-1 (Fig. 3b).