Mannosylated glycans impair normal T-cell development by reprogramming commitment and repertoire diversity

Cell Mol Immunol. 2023 Aug;20(8):955-968. doi: 10.1038/s41423-023-01052-7. Epub 2023 Jun 21.

Abstract

T-cell development ensures the formation of diverse repertoires of T-cell receptors (TCRs) that recognize a variety of antigens. Glycosylation is a major posttranslational modification present in virtually all cells, including T-lymphocytes, that regulates activity/functions. Although these structures are known to be involved in TCR-selection in DP thymocytes, it is unclear how glycans regulate other thymic development processes and how they influence susceptibility to disease. Here, we discovered stage-specific glycome compositions during T-cell development in human and murine thymocytes, as well as dynamic alterations. After restricting the N-glycosylation profile of thymocytes to high-mannose structures, using specific glycoengineered mice (Rag1CreMgat1fl/fl), we showed remarkable defects in key developmental checkpoints, including ß-selection, regulatory T-cell generation and γδT-cell development, associated with increased susceptibility to colon and kidney inflammation and infection. We further demonstrated that a single N-glycan antenna (modeled in Rag1CreMgat2fl/fl mice) is the sine-qua-non condition to ensure normal development. In conclusion, we revealed that mannosylated thymocytes lead to a dysregulation in T-cell development that is associated with inflammation susceptibility.

Keywords: Glycocalyx; Inflammation; N-glycosylation; T-cell development; Thymocytes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Glycosylation
  • Homeodomain Proteins / genetics
  • Humans
  • Mice
  • Polysaccharides
  • Receptors, Antigen, T-Cell / metabolism
  • Thymocytes*
  • Thymus Gland*

Substances

  • Receptors, Antigen, T-Cell
  • Homeodomain Proteins
  • Polysaccharides