Fig. 3.

Analysis of TNF-α expression in CD14+ monocytes by intracellular cytokine staining in acutely infected RSV infants (n = 5) and controls (n = 10). Blood samples were cultured with brefeldin A (10 µg/ml) or LPS (100 ng/ml) and brefeldin A for 4 h. LPS-induced TNF-α was determined by intracellular cytokine staining as described in Methods. Expression of TNF-α in unstimulated cells was always less than 1% in all tested children (data not shown). Each symbol represents one tested infant. n.s. = not significant.