Figure 6

APP-CCE specific IL-10-producing CD4 ⁺ T cells in lung, peripheral blood, tracheobronchial lymph nodes and tonsils. Cells isolated from lung, blood (PBMC), tracheobronchial lymph nodes (TBLN) and tonsils were incubated overnight with APP-CCE, medium or PMA/Ionomycin and subsequently analyzed by FCM. Living cells were gated (not shown; see Additional file 1) and further analyzed for expression of IL-10 and CD4. A For the lung, data from representative animals from different groups are displayed: #5 for the acute phase, designated as “responder”; #17 and #18 for the chronic phase, designated as “outlier” and “responder”, respectively; #6, designated as “non-responder” and control pig #23. Approximately 5 × 10⁵ (APP and medium) and 1.5 × 10⁵ (PMA/Ionomycin) cells are shown in the contour plots. Numbers displayed within the contour plots indicate the percentage of IL-10⁺ CD4⁺ T cells within total CD4⁺ T cells. B Frequency of IL-10⁺ CD4⁺ T cells in lung, PBMC, TBLN and tonsils of infected animals (red dots) and control animals (blue dots) during acute and chronic phase. Numbers next to colored dots indicate numbers of individual animals. Median percent values are indicated by black bars. Medium-corrected percent values are presented (% of IL-10⁺ CD4⁺ T cells within total CD4⁺ T cells for APP-CCE stimulation minus % of IL-10⁺ CD4⁺ T cells within total CD4⁺ T cells for medium incubation).