Figure 9

Schematic representation of the signaling pathways involved in sPLA ₂ -IIA-induced activation of microglial cells. sPLA₂-IIA, via Src-dependent activation, stimulates the shedding of the epidermal growth factor receptor (EGFR) ligand, heparin-binding-EGF, which in turn activates the EGFR. Phosphorylated EGFR results in activation of ERK and Akt/mTOR pathways, and the whole cascade stimulates microglia proliferation and augments their phagocytic activity.