Temporal regulation of Wnt/β-catenin signaling is important for invariant NKT cell development and terminal maturation

Mol Immunol. 2017 May:85:47-56. doi: 10.1016/j.molimm.2017.01.025. Epub 2017 Feb 14.

Abstract

The Wnt/β-catenin signaling pathway plays important roles during various cellular functions including survival and proliferation of immune cells. The critical role of this pathway in conventional T cell development is established but little is known about its contributions to innate T cell development. In this study, we found that β-catenin level, an indication of the strength of Wnt/β-catenin signaling, is regulated during invariant NKT (iNKT) cell development. β-catenin levels were greatly increased during iNKT cell selection from double positive thymocytes to Stage 0 of iNKT cell development and during subsequent development to Stage 1. Thereafter, β-catenin levels decrease from Stage 2, which is essential for the terminal maturation of iNKT cells. Failure to dampen Wnt/β-catenin signaling as in mice expressing a stabilized active form of β-catenin (CATtg) resulted in increased Stage 2 and decreased Stage 3 iNKT cells. Inefficient transition from Stage 2 to 3 in CATtg iNKT cells seems to be contributed by poor expression of IL-15R (CD122) and transcription factor T-bet, both of which are necessary for terminal maturation of iNKT cells in the thymus. Consequently, IFN-γ+ iNKT cells were greatly reduced in CATtg mice. Together, our findings reveal that proper regulation of β-catenin and in turn Wnt signaling plays an important role in the terminal maturation and function of iNKT cells.

Keywords: CD122; Cytokines; PLZF; Wnt/β-catenin; iNKT cell development.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, N.I.H., Intramural

MeSH terms

  • Animals
  • Cell Differentiation / immunology*
  • Flow Cytometry
  • Mice
  • Mice, Inbred C57BL
  • Mice, Transgenic
  • Natural Killer T-Cells / immunology*
  • Real-Time Polymerase Chain Reaction
  • Wnt Signaling Pathway / immunology*