Figure 3.

Effect of non-viable Lactobacillus rhamnosus CRL1505 (HK1505) and its peptidoglycan (PG1505) on respiratory immune cell populations before and after the nasal administration of the viral pathogen-associated molecular pattern poly(I:C). Infant mice were nasally primed with HK1505 or PG1505 during two consecutive days and then challenged with three once-daily doses of poly(I:C). Non-treated infant mice challenged with poly(I:C) were used as controls. Before and 2 days after poly(I:C) administration, the numbers of lung T cells (A) including CD3⁺CD4⁺IFN-γ⁺, CD3⁺CD4⁺IL-10⁺, and CD3⁺CD8⁺IFN-γ⁺ T lymphocytes, as well as antigen presenting cells (B) including MHC-II⁺CD11c⁺CD11b^lowCD103⁺ and MHC-II⁺CD11c⁺CD11b^highCD103⁻ dendritic cells, and CD45⁺CD11c⁺SiglecF⁺ alveolar macrophages were determined by flow cytometry. In addition, bronchoalveolar lavages (BAL) neutrophils and lung CD45⁺CD11c⁻Gr1⁺ cells (C) were determined. The results represent data from three independent experiments. Significant differences between treated and control groups, *P < 0.05.