7ndu

Publication Abstract from PubMed

The nonpolymorphic class Ib molecule, HLA-E, primarily presents peptides from HLA class Ia leader peptides, providing an inhibitory signal to NK cells via CD94/NKG2 interactions. Although peptides of pathogenic origin can also be presented by HLA-E to T cells, the molecular basis underpinning their role in antigen surveillance is largely unknown. Here, we solved a co-complex crystal structure of a TCR with an HLA-E presented peptide (pHLA-E) from bacterial (Mycobacterium tuberculosis) origin, and the first TCR-pHLA-E complex with a noncanonically presented peptide from viral (HIV) origin. The structures provided a molecular foundation to develop a novel method to introduce cysteine traps using non-natural amino acid chemistry that stabilized pHLA-E complexes while maintaining native interface contacts between the TCRs and different pHLA-E complexes. These pHLA-E monomers could be used to isolate pHLA-E-specific T cells, with obvious utility for studying pHLA-E restricted T cells, and for the identification of putative therapeutic TCRs.

Structure-guided stabilization of pathogen-derived peptide-HLA-E complexes using non-natural amino acids conserves native TCR recognition.,Barber C, De Souza VA, Paterson RL, Martin-Urdiroz M, Mulakkal NC, Srikannathasan V, Connolly M, Phillips G, Foong-Leong T, Pengelly R, Karuppiah V, Grant T, Dembek M, Verma A, Gibbs-Howe D, Blicher TH, Knox A, Robinson RA, Cole DK, Leonard S Eur J Immunol. 2022 Apr;52(4):618-632. doi: 10.1002/eji.202149745. Epub 2022 Feb , 13. PMID:35108401^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.