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A Flow Cytometry-Based Cytotoxicity Assay for the Assessment of Human NK Cell Activity
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Natural killer cell cytotoxicity: how do they pull the trigger?

Nicola J Topham1, Eric W Hewitt

  • 1Faculty of Biological Sciences, Institute of Molecular and Cellular Biology, University of Leeds, Leeds, UK.

Immunology
|August 20, 2009
PubMed

Insights

Natural killer (NK) cells kill aberrant cells using cytotoxic molecules released from secretory lysosomes. This process, crucial for immune function, involves specialized exocytosis at the immunological synapse.

Area of Science:

  • Immunology
  • Cell Biology
  • Molecular Biology

Background:

  • Natural killer (NK) cells are crucial immune cells that eliminate aberrant cells, including virally infected and cancerous cells.
  • Cytotoxic molecules essential for NK cell killing are stored in specialized secretory lysosomes.
  • NK cell-mediated cytotoxicity relies on the targeted release of these molecules via exocytosis.

Purpose of the Study:

  • To review recent research on the molecular mechanisms governing NK cell secretory lysosome exocytosis.
  • To discuss the immunological consequences of defects in the exocytic machinery of NK cells.

Main Methods:

  • This review synthesizes findings from recent studies.
  • Focuses on molecular and immunological investigations of NK cell function.

Main Results:

  • NK cell killing is mediated by the polarized exocytosis of cytotoxic molecules from secretory lysosomes at the lytic synapse.
  • Mutations in exocytic machinery components lead to immune disorders, underscoring the importance of this process.

Conclusions:

  • Secretory lysosome exocytosis is fundamental to NK cell cytotoxic function.
  • Understanding the molecular basis of this process is vital for addressing related immune disorders.

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