Inflammatory cell responses in bronchoalveolar lavage (BAL) fluid
following RSV-RFP infection
Total BAL cell numbers were significantly elevated at 5 dpi returning to
baseline by 7 dpi (Figure 2A), while macrophage numbers were
significantly reduced at 3, 5 and 7 dpi, returning to baseline by 21 dpi
(Figure 2B). Total numbers of neutrophils were significantly elevated at
3, 5 and 7 dpi and lymphocytes at 5 dpi, with both cell types returning
to baseline by 21 dpi (Figure 2C and D).
Analysis of the percentage frequency of each cell type in BAL showed a
similar significant trend as for absolute numbers (Figure 2C, E and G).
This analysis showed a very high percentage of neutrophils in BAL;
reaching close to 100% of all BAL cells at 3 and 5 dpi; then declining
but still significantly raised at 7 dpi, remaining elevated but no
longer significantly raised above baseline at 21 dpi (Figure 2E).
Macrophage percentages decreased at 3, 5 and 7 dpi, returning to
baseline by 21 dpi (Figure 2C). While the percentage of lymphocytes were
elevated at 5 dpi, returning to baseline at 7 and 21 dpi (Figure 2G).
Thus, RSV infection induced a significant inflammatory cell response in
BAL at 3, 5 and 7 dpi that was dominated by neutrophils, which had
returned to baseline by 21 dpi.