PI(4,5)P2 ja adaptiivinen immuunipuolustus

https://www.researchgate.net/publication/318500934_Cortical_actin_recovery_at_the_immunological_synapse_
leads_to_termination_of_lytic_granule_secretion_in_cytotoxic_T_lymphocytes

http://www.pnas.org/content/114/32/E6585

Significance

Cytotoxic T lymphocytes (CTLs) destroy virally infected and tumor cells through the directed secretion of specialized lysosomes called “lytic granules.” Because a single CTL must direct its cytotoxic activities only against specific targets but can sequentially kill multiple cells, granule secretion must be tightly controlled. We demonstrate here that dynamic regulation of the cortical actin cytoskeleton is critical for both the initiation and termination of secretion. We further link actin dynamics with phosphatidylinositol 4,5-bisphosphate (PIP₂) levels and provide evidence that lytic granule delivery initiates cortical actin recovery and the cessation of secretion. Our results suggest that actin both regulates and is regulated by secretion, providing a mechanism by which CTLs control their ability to kill targets serially during immune responses.