Detection of C. pneumoniae by a DNA microarray for intracellular pathogens. A) Hybridization results were obtained with genus-specific probes (p) for selected intracellular pathogens. B) Results for all hybridization experiments are represented as a heatmap. Columns correspond to probes and rows to hybridizations. Colors correspond to signal values (green: no signal; black: weak signal; red: strong signal). C) Specific hybridization patterns were obtained for monocytes infected with 2 × 104 IFU (open bars) and 2 × 103 IFU (hatched bars) per 2 × 105 monocytes after 6 h (upper panel) and 48 h (lower panel) post infection with Chlamydia spp. probes. Error bars represent the mean of 4 replicate spots on the microarray. The figures show one representative microarray analysis (n = 3).