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bioRxiv · 10.1101/2022.05.27.493692

Mapping the epitopes of the Human Leukocyte Antigen E antibodies 3D12 and 4D12

Brackenridge, S.·Borrow, P.·McMichael, A. J.
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Abstract

The commonly used commercially available antibodies 3D12 and 4D12 recognise the human leukocyte antigen E (HLA-E) protein. 3D12 is known to exhibit minimal cross-reactivity with classical HLA-Ia allotypes and we confirm that this is also the case for 4D12. These antibodies bind different epitopes on HLA-E, and differ in their ability to recognise alleles of the major histocompatibility complex E (MHC-E) proteins of rhesus and cynomolgus macaques. Using hybrids of different MHC-E alleles, we have mapped the regions that are critical for the binding of these two antibodies. 3D12 recognises a region on the alpha 3 domain that is unique to HLA-E, on the opposite side to that bound by {beta}2-microglobulin, while 4D12 recognises the start of the alpha 2 domain, adjacent to the C terminus of the presented peptide. Knowledge of the binding sites of these two antibodies will facilitate selection of the best antibody for a given application, and inform interpretation of the resulting data.

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Brackenridge, S., Borrow, P., McMichael, A. J.. 2022-05-29. Mapping the epitopes of the Human Leukocyte Antigen E antibodies 3D12 and 4D12. https://doi.org/10.1101/2022.05.27.493692

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