Cumulative Toll-like receptor activation in human macrophages treated with whole bacteria.

Purified components from bacteria selectively activate Toll-like receptors (TLR), leading to shared and unique responses in innate immune cells. Whole bacteria contain agonists for multiple TLR and induce a common macrophage activation program of transcription. It is not known, however, whether the stimulation of specific TLR by whole bacteria results in differential activation of the innate immune system.

Human macrophage activation programs induced by bacterial pathogens.

Understanding the response of innate immune cells to pathogens may provide insights to host defenses and the tactics used by pathogens to circumvent these defenses. We used DNA microarrays to explore the responses of human macrophages to a variety of bacteria. Macrophages responded to a broad range of bacteria with a robust, shared pattern of gene expression.