1. Schematic model illustrating how paracrine signaling drives LPS-stimulated cytokine secretion.
Schematic model illustrating how paracrine signaling drives LPS-stimulated cytokine secretion. Most macrophages stimulated with LPS secrete CCL4, CCL5, and IL-8, whereas a smaller percentage of cells secrete IL-1β, TNF-α, GM-CSF, IL-6, and IL-10. The secretion of IL-6 and IL-10 is dependent on paracrine signals from the subset of cells that secrete IL-1β, TNF-α, GM-CSF, and other factors not measured in our study. The secretion of IL-10 further depends on paracrine signaling by IL-6. IL-10 is the cytokine whose secretion was most adversely affected by the isolation of MDM cells. Cells that secrete IL-10 inhibit the secretion of TNF-α, GM-CSF, and IL-6, as well as of some chemokines (21, 32, 33), which may account for the increased concentrations of TNF-α and GM-CSF that were secreted by isolated MDMs.
Qiong Xue et al., Sci. Signal. 2015;8:ra59
Copyright © 2015, American Association for the Advancement of Science