Recombinant suilysin of Streptococcus suis enhances the protective efficacy of an engineered Pasteurella multocida toxin protein

Min-Chia Wu; Thu-Dung Doan; Jai-Wei Lee; Yi-Ting Lo; Hsing-Chieh Wu; Chun-Yen Chu

doi:10.1016/j.rvsc.2022.08.016

Recombinant suilysin of Streptococcus suis enhances the protective efficacy of an engineered Pasteurella multocida toxin protein

Res Vet Sci. 2022 Dec 10:151:175-183. doi: 10.1016/j.rvsc.2022.08.016. Epub 2022 Aug 24.

Authors

Min-Chia Wu¹, Thu-Dung Doan², Jai-Wei Lee³, Yi-Ting Lo¹, Hsing-Chieh Wu⁴, Chun-Yen Chu⁵

Affiliations

¹ International Degree Program in Animal Vaccine Technology, International College, National Pingtung University of Science and Technology, Pingtung, Taiwan.
² International Degree Program in Animal Vaccine Technology, International College, National Pingtung University of Science and Technology, Pingtung, Taiwan; General Research Service Center, National Pingtung University of Science and Technology, Pingtung 91201, Taiwan; Graduate Institute of Animal Vaccine Technology, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, Taiwan.
³ Department of Tropical Agriculture and International Cooperation, National Pingtung University of Science and Technology, Pingtung, Taiwan.
⁴ International Degree Program in Animal Vaccine Technology, International College, National Pingtung University of Science and Technology, Pingtung, Taiwan; Graduate Institute of Animal Vaccine Technology, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, Taiwan.
⁵ International Degree Program in Animal Vaccine Technology, International College, National Pingtung University of Science and Technology, Pingtung, Taiwan; Graduate Institute of Animal Vaccine Technology, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, Taiwan. Electronic address: cychu@mail.npust.edu.tw.

PMID: 36041311
DOI: 10.1016/j.rvsc.2022.08.016

Abstract

Suilysin (Sly) from Streptococcus suis has been shown to elicit strong immune responses and may act as a vaccine adjuvant. In the present study, we tested the adjuvant effect of Sly using an engineered Pasteurella multocida toxin, rPMT-NC, as the antigen. The antigen was also formulated with other conventional adjuvants (aluminum hydroxide, water-in-oil-in-water) for comparison. The efficacy of these vaccine formulations were evaluated in mice. The optimal dosage of purified rSly for enhancing immune responses in mice was first determined to be 40 μg/ml based on significantly (p < 0.05) increased serum antibody titers, expression of cytokines, including interleukin (IL)-4, IL-12, and interferon (IFN)-γ and the survival rate after challenge with P. multocida. Mice immunized with rPMT-NC + rSly had augmented antibody production and cellular immunity compare to those immunized with rPMT-NC plus other adjuvants. In addition, the survival rate of mice immunized with rPMT-NC + rSly was the highest (70% v.s. 30% of mice immunized with rPMT-NC alone) among all groups. In conclusion, rSly has the potential to be used as a biological adjuvant to enhance immune responses and protective efficacy of protein-based vaccines.

Keywords: Adjuvant; Pasteurella multocida toxin; Recombinant protein; Streptococus suis; Subunit vaccine; Suilysin.

MeSH terms

Adjuvants, Immunologic / pharmacology
Animals
Bacterial Proteins
Bacterial Toxins
Hemolysin Proteins
Mice
Pasteurella multocida*
Streptococcus suis*
Water

Substances

Adjuvants, Immunologic
Bacterial Proteins
Bacterial Toxins
Hemolysin Proteins
Pasteurella multocida toxin
suilysin
Water