Use of "one-pot, mix-and-read" peptide-MHC class I tetramers and predictive algorithms to improve detection of cytotoxic T lymphocyte responses in cattle.

Abstract

Peptide-major histocompatibility complex (p-MHC) class I tetramer complexes have facilitated the early detection and functional characterisation of epitope specific CD8+ cytotoxic T lymphocytes (CTL). Here, we report on the generation of seven recombinant bovine leukocyte antigens (BoLA) and recombinant bovine β2-microglobulin from which p-MHC class I tetramers can be derived in ~48 h. We validated a set of p-MHC class I tetramers against a panel of CTL lines specific to seven epitopes on five different antigens of Theileria parva, a protozoan pathogen causing the lethal bovine disease East Coast fever. One of the p-MHC class I tetramers was tested in ex vivo assays and we detected T. parva specific CTL in peripheral blood of cattle at day 15-17 post-immunization with a live parasite vaccine. The algorithm NetMHCpan predicted alternative epitope sequences for some of the T. parva CTL epitopes. Using an ELISA assay to measure peptide-BoLA monomer formation and p-MHC class I tetramers of new specificity, we demonstrate that a predicted alternative epitope Tp229-37 rather than the previously reported Tp227-37 epitope is the correct Tp2 epitope presented by BoLA-6*04101. We also verified the prediction by NetMHCpan that the Tp587-95 epitope reported as BoLA-T5 restricted can also be presented by BoLA-1*02301, a molecule similar in sequence to BoLA-T5. In addition, Tp587-95 specific bovine CTL were simultaneously stained by Tp5-BoLA-1*02301 and Tp5-BoLA-T5 tetramers suggesting that one T cell receptor can bind to two different BoLA MHC class I molecules presenting the Tp587-95 epitope and that these BoLA molecules fall into a single functional supertype.

• Authors: Nicholas Svitek, Andreas Martin Hansen, Lucilla Steinaa, Rosemary Saya, Elias Awino, Morten Nielsen, Søren Buus, Vishvanath Nene
• Journal: Veterinary research (Vet Res) Vol. 45 Pg. 50 (Apr 28 2014) ISSN: 1297-9716 [Electronic] England
• PMID: 24775445 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, Non-P.H.S.)

Chemical References

• Epitopes, T-Lymphocyte
• Histocompatibility Antigens
• beta 2-Microglobulin

Topics

• Algorithms
• Amino Acid Sequence
• Animals
• Cattle
• Enzyme-Linked Immunosorbent Assay (veterinary)
• Epitopes, T-Lymphocyte (immunology)
• Histocompatibility Antigens
• Major Histocompatibility Complex
• Molecular Sequence Data
• Sequence Alignment (veterinary)
• T-Lymphocytes, Cytotoxic (immunology)
• Theileria parva (immunology)
• beta 2-Microglobulin (immunology)