Development of anti-thrombotic vaccine against human S100A9 in rhesus monkey

Munehisa Shimamura,Shota Yoshida,Tomohiro Kawano,Ryo Nakamaru,Hiroki Hayashi,Tsutomu Sasaki,Nan Ju,Kenichi Tsujita,Hideki Mochizuki,Ryuichi Morishita,Hironori Nakagami,Koichi Kaikita

doi:10.1038/s41598-021-91153-y

Munehisa Shimamura, Shota Yoshida + Show 10 more

Open Access

https://doi.org/10.1038/s41598-021-91153-y

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Journal: Scientific Reports	Publication Date: Jun 1, 2021
Citations: 4	License type: open-access

Affiliation: Osaka University, Kumamoto University

Abstract

In post-stroke patients, a decreased adherence to antiplatelet drugs is a major challenge in the prevention of recurrent stroke. Previously, we reported an antiplatelet vaccine against S100A9 in mice, but the use of Freund’s adjuvant and the difference in amino acid sequences in epitopes between mice and humans were problematic for clinical use. Here, we redesigned the S100A9 vaccine for the common sequence in both humans and monkeys and examined its effects in cynomolgus monkeys with Alum adjuvant. First, we assessed several candidate epitopes and selected 102 to 112 amino acids as the suitable epitope, which could produce antibodies. When this peptide vaccine was intradermally injected into 4 cynomolgus monkeys with Alum, the antibody against human S100A9 was successfully produced. Anti-thrombotic effects were shown in two monkeys in a mixture of vaccinated serum and fresh whole blood from another cynomolgus monkey. Additionally, the anti-thrombotic effects were partially inhibited by the epitope peptide, indicating the feasibility of neutralizing anti-thrombotic effects of produced antibodies. Prolongation of bleeding time was not observed in vaccinated monkeys. Although further studies on increasing the effect of vaccine and safety are necessary, this vaccine will be a promising approach to improve adherence to antiplatelet drugs in clinical settings.

Highlights

In post-stroke patients, a decreased adherence to antiplatelet drugs is a major challenge in the prevention of recurrent stroke
Based on results of computed epitope prediction (Bepipred Linear Epitope Prediction), we first assessed whether other candidate epitopes, 2 to 11 or 97–106 amino acids, where the amino acid sequence is approximately similar between humans and monkeys, could raise antibodies against S100 calcium-binding protein A9 (S100A9) in mice (Fig. 1A)
We have reported the efficacy of the anti-S100A9 vaccine in mice; the amino acid sequence differs between humans and mice

Summary

Introduction

In post-stroke patients, a decreased adherence to antiplatelet drugs is a major challenge in the prevention of recurrent stroke. The mechanism of anti-thrombotic effects without increasing the risk of bleeding has not been clarified, the platelet from S 100A9−/− mice showed less GpIIb/IIIa activation on collagen under flow c onditions[5] Based on this finding, we have developed an S100A9 vaccine, which could produce antibodies against S100A9 and induce long-term anti-thrombotic effects without affecting bleeding time[6]. We have developed an S100A9 vaccine, which could produce antibodies against S100A9 and induce long-term anti-thrombotic effects without affecting bleeding time[6] This vaccine is a KLH-conjugated B-cell epitope vaccine, including 104 to 113 amino acid sequence at the C-terminus of S100A9, which could avoid harmful T cell responses against self-S100A9 and Th1 predominant immune r esponse[6]. We examined the reversal effects of epitope peptide for anti-thrombotic effects to clarify whether the produced antibody recognizes the epitope

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Conclusion