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bioRxiv · 10.1101/2021.04.22.441021

Citrullination of a phage displayed human peptidome library reveals the fine specificities of rheumatoid arthritis-associated autoantibodies

Roman-Melendez, G. D.·Monaco, D. R.·Montagne, J. M.·Quizon, R. S.·Konig, M. F.·Astatke, M.·Darrah, E.·Larman, H. B.
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Abstract

Post-translational modifications (PTMs) on proteins can be targeted by antibodies associated with autoimmunity. Despite a growing appreciation for their intrinsic role in disease, there is a lack of highly multiplexed serological assays to characterize the fine specificities of PTM-directed autoantibodies. In this study, we used the programmable phage display technology, Phage ImmunoPrecipitation Sequencing (PhIP-Seq), to profile rheumatoid arthritis (RA) associated anti-citrullinated protein antibody (ACPA) reactivities. Using both an unmodified and peptidylarginine deiminases (PAD)-modified phage display library consisting of ~250,000 overlapping 90 amino acid peptide tiles spanning the human proteome, PTM PhIP-Seq robustly identifies antibodies to citrulline-dependent epitopes. PTM PhIP-Seq was used to quantify key differences among RA patients, including PAD isoform specific ACPA profiles, and thus represents a powerful tool for proteome-scale antibody-binding analyses.

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Roman-Melendez, G. D., Monaco, D. R., Montagne, J. M., Quizon, R. S., Konig, M. F., Astatke, M., Darrah, E., Larman, H. B.. 2021-04-23. Citrullination of a phage displayed human peptidome library reveals the fine specificities of rheumatoid arthritis-associated autoantibodies. https://doi.org/10.1101/2021.04.22.441021

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