Regulation of Asymmetric Division by Atypical Protein Kinase C Influences Early Specification of CD8(+) T Lymphocyte Fates

Sci Rep. 2016 Jan 14:6:19182. doi: 10.1038/srep19182.

Abstract

Naïve CD8(+) T lymphocytes responding to microbial pathogens give rise to effector T cells that provide acute defense and memory T cells that provide long-lived immunity. Upon activation, CD8(+) T lymphocytes can undergo asymmetric division, unequally distributing factors to the nascent daughter cells that influence their eventual fate towards the effector or memory lineages. Individual loss of either atypical protein kinase C (aPKC) isoform, PKCζ or PKCλ/ι, partially impairs asymmetric divisions and increases CD8(+) T lymphocyte differentiation toward a long-lived effector fate at the expense of memory T cell formation. Here, we show that deletion of both aPKC isoforms resulted in a deficit in asymmetric divisions, increasing the proportion of daughter cells that inherit high amounts of effector fate-associated molecules, IL-2Rα, T-bet, IFNγR, and interferon regulatory factor 4 (IRF4). However, unlike CD8(+) T cells deficient in only one aPKC isoform, complete loss of aPKC unexpectedly increased CD8(+) T cell differentiation toward a short-lived, terminal effector fate, as evidenced by increased rates of apoptosis and decreased expression of Eomes and Bcl2 early during the immune response. Together, these results provide evidence for an important role for asymmetric division in CD8(+) T lymphocyte fate specification by regulating the balance between effector and memory precursors at the initiation of the adaptive immune response.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptive Immunity
  • Animals
  • Asymmetric Cell Division*
  • CD8-Positive T-Lymphocytes / cytology*
  • CD8-Positive T-Lymphocytes / physiology*
  • Cell Differentiation*
  • Gene Knockout Techniques
  • Immunologic Memory
  • Lymphocyte Activation / genetics
  • Lymphocyte Activation / immunology
  • Mice
  • Protein Kinase C / deficiency
  • Protein Kinase C / genetics
  • Protein Kinase C / metabolism*
  • T-Lymphocyte Subsets / cytology
  • T-Lymphocyte Subsets / physiology

Substances

  • Protein Kinase C