These evidences suggest that, in the process of neuroinflammation induced by stroke or LPS, microglia are more sensitive to pathogens/damage and activated via PAMP/DAMP and release the common “molecular signals” or primary mediators, such as IL- 1 and TNF-α, to trigger reactive astrocytes, while astrocytes are unresponsive to pathogens/damage in the absence of microglial cells. The gene discussed is TNF; the disease is stroke disorder.