Structural determination of lipid antigens captured at the CD1d–T-cell receptor interface

Patrick Joseph Brennan, Tan-Yun Cheng, Daniel G. Pellicci, Gerald F.M. Watts, Natacha Veerapen, David C. Young, Jamie Rossjohn, Gurdyal S Besra, Dale I. Godfrey, Michael B Brenner, David Branch Moody

Research output: Contribution to journalArticleResearchpeer-review

25 Citations (Scopus)


Glycolipid antigens recognized by αβ T-cell receptors (TCRs) drive the activation of invariant natural killer T (iNKT) cells, a specialized subset of innate T lymphocytes. Glycolipids with α-linked anomeric carbohydrates have been identified as potent microbial lipid antigens for iNKT cells, and their unusual α-anomeric linkage has been thought to define a “foreign” lipid antigen motif. However, mammals use endogenous lipids to select iNKT cells, and there is compelling evidence for iNKT cell responses in various types of sterile inflammation. The nature of endogenous or environmental lipid antigens encountered by iNKT cells is not well defined. Here, we sought to identify lipid antigens in cow’s milk, a prominent part of the human diet. We developed a method to directly capture lipid antigens within CD1d–lipid–TCR complexes, while excluding CD1d bound to nonantigenic lipids, followed by direct biochemical analysis of the lipid antigens trapped at the TCR–CD1d interface. The specific antigens captured by this “TCR trap” method were identified as α-linked monohexosylceramides by mass spectrometry fragmentation patterns that distinguished α- from β-anomeric monohexosylceramides. These data provide direct biochemical evidence for α-linked lipid antigens from a common dietary source.

Original languageEnglish
Pages (from-to)8348-8353
Number of pages6
JournalProceedings of the National Academy of Sciences of the United States of America
Issue number31
Publication statusPublished - 1 Aug 2017


  • CD1d
  • glycolipid
  • iNKT
  • lipid antigen
  • NKT

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