Secretory cytotoxic granule maturation and exocytosis require the effector protein hMunc13-4

@article{Mnager2007SecretoryCG,
  title={Secretory cytotoxic granule maturation and exocytosis require the effector protein hMunc13-4},
  author={Micka{\"e}l M. M{\'e}nager and Ga{\"e}l M{\'e}nasch{\'e} and Maryse Romao and Perrine Knapnougel and Chen-Hsuan Ho and M{\'e}riem Garfa and Graça Raposo and J{\'e}r{\^o}me Feldmann and Alain Fischer and Genevi{\'e}ve de Saint Basile},
  journal={Nature Immunology},
  year={2007},
  volume={8},
  pages={257-267}
}
Cytotoxic T lymphocytes and natural killer cells exert their cytotoxic activity through the polarized secretion of cytotoxic granules at the immunological synapse. Rab27a and hMunc13-4 are critical effectors of the exocytosis of cytotoxic granules. Here we show that the cytotoxic function of lymphocytes requires the cooperation of two types of organelles: the lysosomal cytotoxic granule and the endosomal 'exocytic vesicle'. Independently of Rab27a, hMunc13-4 mediated the assembly of Rab11… 
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Lytic granules of NK cells are indispensable for normal NK cell cytolytic function and the advancements in understanding the mechanisms controlling their exocytosis are focused on.
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Genevieve de Saint Basile* ‡ § , Gael Menasche* ‡ and Alain Fischer* ‡|| Abstract | Cytotoxic T cells and natural killer cells are crucial for immune surveillance against virus-infected cells and
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This work has shown that a highly flexible system that could enable a cytolytic cell to subsequently kill target cells bound at different sites around the effector cell is possible.
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TLDR
It is reported that CD8+ T cells from acid sphingomyelinase-deficient (ASMase)-deficient mice are defective in exocytosis of cytolytic effector molecules; this defect resulted in attenuated cytotoxic activity of ASMase-KO CD8 + T cells and delayed elimination of lymphocytic choriomeningitis virus from ASMases-KO mice.
Natural killer cell cytotoxicity: how do they pull the trigger?
TLDR
This review will discuss recent studies on the molecular basis for NK cell secretory lysosome exocytosis and the immunological consequences of defects in the exocytic machinery.
Two modes of lytic granule fusion during degranulation by natural killer cells
TLDR
Lytic granules in NK cells undergo both complete and incomplete fusion with the PM, and it is proposed that incomplete fusion may promote efficient recycling of lytic granule membrane after the release of cytotoxic effector molecules.
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