| Structural highlights
Function
TRBC2_HUMAN Constant region of T cell receptor (TR) beta chain (PubMed:24600447). Alpha-beta T cell receptors are antigen specific receptors which are essential to the immune response and are present on the cell surface of T lymphocytes. Recognize peptide-major histocompatibility (MH) (pMH) complexes that are displayed by antigen presenting cells (APC), a prerequisite for efficient T cell adaptive immunity against pathogens (PubMed:25493333). Binding of alpha-beta TR to pMH complex initiates TR-CD3 clustering on the cell surface and intracellular activation of LCK that phosphorylates the ITAM motifs of CD3G, CD3D, CD3E and CD247 enabling the recruitment of ZAP70. In turn, ZAP70 phosphorylates LAT, which recruits numerous signaling molecules to form the LAT signalosome. The LAT signalosome propagates signal branching to three major signaling pathways, the calcium, the mitogen-activated protein kinase (MAPK) kinase and the nuclear factor NF-kappa-B (NF-kB) pathways, leading to the mobilization of transcription factors that are critical for gene expression and essential for T cell growth and differentiation (PubMed:23524462). The T cell repertoire is generated in the thymus, by V-(D)-J rearrangement. This repertoire is then shaped by intrathymic selection events to generate a peripheral T cell pool of self-MH restricted, non-autoaggressive T cells. Post-thymic interaction of alpha-beta TR with the pMH complexes shapes TR structural and functional avidity (PubMed:15040585).[1] [2] [3] [4]
Publication Abstract from PubMed
Rare individuals, termed HIV controllers, spontaneously control HIV infection by mounting efficient T cell responses against the virus. Protective CD4(+) T cell responses from HIV controllers involve high-affinity public T cell receptors (TCRs) recognizing an immunodominant capsid epitope (Gag293) presented by a remarkably broad array of human leukocyte antigen (HLA) class II molecules. Here, we determine the structures of a prototypical public TCR bound to HLA-DR1, HLA-DR11, and HLA-DR15 molecules presenting the Gag293 epitope. TCR recognition was driven by contacts with the Gag293 epitope, a feature that underpinned the extensive HLA cross-restriction. These high-affinity TCRs promoted mature immunological synapse formation and cytotoxic capacity in both CD4(+) and CD8(+) T cells. The public TCRs suppressed HIV replication in multiple genetic backgrounds ex vivo, emphasizing the functional advantage conferred by broad HLA class II cross-restriction.
CD4(+) T cell-mediated HLA class II cross-restriction in HIV controllers.,Galperin M, Farenc C, Mukhopadhyay M, Jayasinghe D, Decroos A, Benati D, Tan LL, Ciacchi L, Reid HH, Rossjohn J, Chakrabarti LA, Gras S Sci Immunol. 2018 Jun 8;3(24). pii: 3/24/eaat0687. doi:, 10.1126/sciimmunol.aat0687. PMID:29884618[5]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Nikolich-Zugich J, Slifka MK, Messaoudi I. The many important facets of T-cell repertoire diversity. Nat Rev Immunol. 2004 Feb;4(2):123-32. doi: 10.1038/nri1292. PMID:15040585 doi:http://dx.doi.org/10.1038/nri1292
- ↑ Brownlie RJ, Zamoyska R. T cell receptor signalling networks: branched, diversified and bounded. Nat Rev Immunol. 2013 Apr;13(4):257-69. doi: 10.1038/nri3403. PMID:23524462 doi:http://dx.doi.org/10.1038/nri3403
- ↑ Lefranc MP. Immunoglobulin and T Cell Receptor Genes: IMGT((R)) and the Birth and Rise of Immunoinformatics. Front Immunol. 2014 Feb 5;5:22. doi: 10.3389/fimmu.2014.00022. eCollection 2014. PMID:24600447 doi:http://dx.doi.org/10.3389/fimmu.2014.00022
- ↑ Rossjohn J, Gras S, Miles JJ, Turner SJ, Godfrey DI, McCluskey J. T cell antigen receptor recognition of antigen-presenting molecules. Annu Rev Immunol. 2015;33:169-200. doi: 10.1146/annurev-immunol-032414-112334., Epub 2014 Dec 10. PMID:25493333 doi:http://dx.doi.org/10.1146/annurev-immunol-032414-112334
- ↑ Galperin M, Farenc C, Mukhopadhyay M, Jayasinghe D, Decroos A, Benati D, Tan LL, Ciacchi L, Reid HH, Rossjohn J, Chakrabarti LA, Gras S. CD4(+) T cell-mediated HLA class II cross-restriction in HIV controllers. Sci Immunol. 2018 Jun 8;3(24). pii: 3/24/eaat0687. doi:, 10.1126/sciimmunol.aat0687. PMID:29884618 doi:http://dx.doi.org/10.1126/sciimmunol.aat0687
|
