Cell Reports (Jun 2022)

Vps33B controls Treg cell suppressive function through inhibiting lysosomal nutrient sensing complex-mediated mTORC1 activation

  • Hongrui Xiang,
  • Yuexiao Tao,
  • Zhenyan Jiang,
  • Xian Huang,
  • Huizi Wang,
  • Wei Cao,
  • Jia Li,
  • Rui Ding,
  • Mingyi Shen,
  • Ru Feng,
  • Linsen Li,
  • Chenyang Guan,
  • Jiamin Liu,
  • Jun Ni,
  • Lei Chen,
  • Zhengting Wang,
  • Youqiong Ye,
  • Qing Zhong,
  • Junling Liu,
  • Qiang Zou,
  • Xuefeng Wu

Journal volume & issue
Vol. 39, no. 11
p. 110943

Abstract

Read online

Summary: The suppressive function of regulatory T (Treg) cells is tightly controlled by nutrient-fueled mechanistic target of rapamycin complex 1 (mTORC1) activation, yet its dynamics and negative regulation remain unclear. Here we show that Treg-specific depletion of vacuolar protein sorting 33B (Vps33B) in mice results in defective Treg cell suppressive function and acquisition of effector phenotype, which in turn leads to disturbed T cell homeostasis and boosted antitumor immunity. Mechanistically, Vps33B binds with lysosomal nutrient-sensing complex (LYNUS) and promotes late endosome and lysosome fusion and clearance of the LYNUS-containing late endosome/lysosome, and therefore suppresses mTORC1 activation. Vps33B deficiency in Treg cells results in disordered endosome lysosome fusion, which leads to accumulation of LYNUS that causes elevated mTORC1 activation and hyper-glycolytic metabolism. Taken together, our study reveals that Vps33B maintains Treg cell suppressive function through sustaining endolysosomal homeostasis and therefore restricting amino acid-licensed mTORC1 activation and metabolism.

Keywords