Intra-lineage Plasticity and Functional Reprogramming Maintain Natural Killer Cell Repertoire Diversity

Cell Rep. 2019 Nov 19;29(8):2284-2294.e4. doi: 10.1016/j.celrep.2019.10.058.


Natural killer (NK) cell repertoires are made up of phenotypically distinct subsets with different functional properties. The molecular programs involved in maintaining NK cell repertoire diversity under homeostatic conditions remain elusive. Here, we show that subset-specific NK cell proliferation kinetics correlate with mTOR activation, and global repertoire diversity is maintained through a high degree of intra-lineage subset plasticity during interleukin (IL)-15-driven homeostatic proliferation in vitro. Slowly cycling sorted KIR+CD56dim NK cells with an induced CD57 phenotype display increased functional potential associated with increased transcription of genes involved in adhesion and immune synapse formation. Rapidly cycling cells upregulate NKG2A, display a general loss of functionality, and a transcriptional signature associated with increased apoptosis/cellular stress, actin-remodeling, and nuclear factor κB (NF-κB) activation. These results shed light on the role of intra-lineage plasticity during NK cell homeostasis and suggest that the functional fate of the cell is tightly linked to the acquired phenotype and transcriptional reprogramming.

Keywords: IL-15; differentiation; education; homeostasis; killer cell immunoglobulin-like receptors; natural killer cells; plasticity; single-cell RNA sequencing.

MeSH terms

  • Apoptosis / genetics
  • Apoptosis / physiology
  • CD56 Antigen / metabolism
  • CD57 Antigens / metabolism
  • Humans
  • Interleukin-15 / metabolism
  • Killer Cells, Natural / metabolism*
  • Kinetics
  • NF-kappa B / metabolism
  • NK Cell Lectin-Like Receptor Subfamily C / metabolism
  • Phenotype
  • Sequence Analysis, RNA
  • Synapses / metabolism


  • CD56 Antigen
  • CD57 Antigens
  • IL15 protein, human
  • Interleukin-15
  • KLRC1 protein, human
  • NF-kappa B
  • NK Cell Lectin-Like Receptor Subfamily C