Find-Me Signals in Cell Clearance and Immunity
Cells undergoing apoptosis release soluble cues called “find-me” signals that promote the recruitment of phagocytes and aid in the phagocytic clearance of dying cells. Triphosphate nucleotides (ATP and UTP), acting via P2Y receptors on phagocytes, were recently identified as such a find-me cue. In addition to acting as recruitment signals, we have found that ATP released by apoptotic cells can drive a powerful anti-inflammatory response in macrophages via the CD73-dependent activation of the A2a and A2b adenosine receptors. Current studies are underway to further understand the molecular regulation and physiologic consequences of find-me signaling in multiple aspects of immune-related diseases, including inflammation, fibrosis, HIV-1 infection and cancer immunotherapy.
Identification of dying cells (TUNEL+(red)) in the murine thymus along with cortical epithelial cells (cytokeratin(green)).
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