Evaluation of the immunoprotective effects of IF-2 GTPase and SSU05-1022 as Streptococcus suis candidate subunit vaccine

Aim: This study aims to develop a subunit vaccine with high cross-protection for Streptococcus suis. Materials & methods: Four-week-old female BALB/c mice were first immunized with a single and mixed protein. Various indicators, such as antibody titers and various cytokine levels, were further analyzed. Results: The results showed that purified recombinant proteins IF-2 and 1022 had a good protective effect against lethal doses of S. suis serotype 2 and S. suis serotype 9. This study showed immunization with recombinant proteins. Conclusion: IF-2 and 1022 can enhance cross-protection against S. suis serotypes 2 and 9.

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Purification, Stability, and Immunogenicity Analyses of Five Bluetongue Virus Proteins for Use in Development of a Subunit Vaccine That Allows Differentiation of Infected from Vaccinated Animals

Clinical and Vaccine Immunology ◽

10.1128/cvi.00776-13 ◽

2014 ◽

Vol 21 (3) ◽

pp. 443-452 ◽

Cited By ~ 7

Author(s):

Jenna Anderson ◽

Emmanuel Bréard ◽

Karin Lövgren Bengtsson ◽

Kjell-Olov Grönvik ◽

Stéphan Zientara ◽

...

Keyword(s):

Bluetongue Virus ◽

Subunit Vaccine ◽

Clinical Signs ◽

Igg Antibody ◽

Content Type ◽

Vector Borne Diseases ◽

Antibody Titers ◽

A Subunit ◽

Bluetongue Disease ◽

Vector Borne

ABSTRACTBluetongue virus (BTV) causes bluetongue disease, a vector-borne disease of ruminants. The recent northerly spread of BTV serotype 8 in Europe resulted in outbreaks characterized by clinical signs in cattle, including unusual teratogenic effects. Vaccination has been shown to be crucial for controlling the spread of vector-borne diseases such as BTV. With the aim of developing a novel subunit vaccine targeting BTV-8 that allows differentiation of infected from vaccinated animals, five His-tagged recombinant proteins, VP2 and VP5 of BTV-8 and NS1, NS2, and NS3 of BTV-2, were expressed in baculovirus orEscherichia coliexpression systems for further study. Optimized purification protocols were determined for VP2, NS1, NS2, and NS3, which remained stable for detection for at least 560 to 610 days of storage at +4°C or −80°C, and Western blotting using sera from vaccinated or experimentally infected cattle indicated that VP2 and NS2 were recognized by BTV-specific antibodies. To characterize murine immune responses to the four proteins, mice were subcutaneously immunized twice at a 4-week interval with one of three protein combinations plus immunostimulating complex ISCOM-Matrix adjuvant or with ISCOM-Matrix alone (n= 6 per group). Significantly higher serum IgG antibody titers specific for VP2 and NS2 were detected in immunized mice than were detected in controls. VP2, NS1, and NS2 but not NS3 induced specific lymphocyte proliferative responses upon restimulation of spleen cells from immunized mice. The data suggest that these recombinant purified proteins, VP2, NS1, and NS2, could be an important part of a novel vaccine design against BTV-8.

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Biochemical and Immunological Evaluation of Recombinant CS6-Derived Subunit EnterotoxigenicEscherichia coliVaccine Candidates

Infection and Immunity ◽

10.1128/iai.00788-18 ◽

2019 ◽

Vol 87 (3) ◽

Cited By ~ 4

Author(s):

Steven T. Poole ◽

Milton Maciel ◽

Premkumar Dinadayala ◽

Kathleen E. Dori ◽

Annette L. McVeigh ◽

...

Keyword(s):

Immune Responses ◽

Recombinant Proteins ◽

Neutralizing Antibodies ◽

Subunit Vaccine ◽

Vaccine Strategy ◽

Content Type ◽

A Subunit ◽

Folded Proteins ◽

Immunological Evaluation

ABSTRACTCS6, a prevalent surface antigen expressed in nearly 20% of clinical enterotoxigenicEscherichia coli(ETEC) isolates, is comprised of two major subunit proteins, CssA and CssB. Using donor strand complementation, we constructed a panel of recombinant proteins of 1 to 3 subunits that contained combinations of CssA and/or CssB subunits and a donor strand, a C-terminal extension of 16 amino acids that was derived from the N terminus of either CssA or CssB. While the entire panel of recombinant proteins could be obtained as soluble, folded proteins, it was observed that the proteins possessing a heterologous donor strand, derived from the CS6 subunit different from the C-terminal subunit, had the highest degree of physical and thermal stability. Immunological characterization of the proteins, using a murine model, demonstrated that robust anti-CS6 immune responses were generated from fusions containing both CssA and CssB. Proteins containing only CssA were weakly immunogenic. Heterodimers, i.e., CssBA and CssAB, were sufficient to recapitulate the anti-CS6 immune response elicited by immunization with CS6, including the generation of functional neutralizing antibodies, as no further enhancement of the response was obtained with the addition of a third CS6 subunit. Our findings here demonstrate the feasibility of including a recombinant CS6 subunit protein in a subunit vaccine strategy against ETEC.

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Sterilizing immunity against SARS-CoV-2 in hamsters conferred by a novel recombinant subunit vaccine

10.1101/2020.12.18.423552 ◽

2020 ◽

Author(s):

Yangtao Wu ◽

Xiaofen Huang ◽

Lunzhi Yuan ◽

Shaojuan Wang ◽

Yali Zhang ◽

...

Keyword(s):

T Cell ◽

Subunit Vaccine ◽

Vaccine Candidate ◽

Protective Efficacy ◽

Humoral Response ◽

Neutralizing Antibody ◽

Cell Immune Response ◽

Antibody Titers ◽

A Subunit ◽

Sterilizing Immunity

AbstractA safe and effective SARS-CoV-2 vaccine is essential to avert the on-going COVID-19 pandemic. Here, we developed a subunit vaccine, which is comprised of CHO-expressed spike ectodomain protein (StriFK) and nitrogen bisphosphonates-modified zinc-aluminum hybrid adjuvant (FH002C). This vaccine candidate rapidly elicited the robust humoral response, Th1/Th2 balanced helper CD4 T cell and CD8 T cell immune response in animal models. In mice, hamsters, and non-human primates, 2-shot and 3-shot immunization of StriFK-FH002C generated 28- to 38-fold and 47- to 269-fold higher neutralizing antibody titers than the human COVID-19 convalescent plasmas, respectively. More importantly, the StriFK-FH002C immunization conferred sterilizing immunity to prevent SARS-CoV-2 infection and transmission, which also protected animals from virus-induced weight loss, COVID-19-like symptoms, and pneumonia in hamsters. Vaccine-induced neutralizing and cell-based receptor-blocking antibody titers correlated well with protective efficacy in hamsters, suggesting vaccine-elicited protection is immune-associated. The StriFK-FH002C provided a promising SARS-CoV-2 vaccine candidate for further clinical evaluation.

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Streptococcus suis Bacterin and Subunit Vaccine Immunogenicities and Protective Efficacies against Serotypes 2 and 9

Clinical and Vaccine Immunology ◽

10.1128/cvi.00371-08 ◽

2008 ◽

Vol 16 (2) ◽

pp. 200-208 ◽

Cited By ~ 60

Author(s):

Christoph Georg Baums ◽

Christoph Kock ◽

Andreas Beineke ◽

Katharina Bennecke ◽

Ralph Goethe ◽

...

Keyword(s):

Subunit Vaccine ◽

Protective Efficacy ◽

Streptococcus Suis ◽

High Serum ◽

Swine Production ◽

Protein Map ◽

Associated Proteins ◽

Antibody Titers ◽

Extracellular Factor ◽

Homologous Challenge

ABSTRACT Streptococcus suis causes numerous diseases in pigs, most importantly, meningitis, arthritis, septicemia, and bronchopneumonia. One of the major problems in modern swine production is the lack of a vaccine protecting against more than one S. suis serotype. The objective of this study was to determine the protective efficacy of a serotype 2 murein-associated protein (MAP) fraction subunit vaccine in comparison to that of a bacterin against experimental challenge with serotype 2 (containing muramidase-released protein [MRP], extracellular factor, and suilysin [SLY]) and serotype 9 (containing MRP variant MRP* and SLY) strains. MAP was shown to include different surface-associated proteins, such as the MRP and surface antigen one (SAO) expressed by both pathotypes used for challenge. The results of this study demonstrated that the serotype 2 bacterin induced protective immunity against homologous challenge. In contrast, the protective efficacy of the MAP subunit vaccine was low, though MAP immunization resulted in high serum immunoglobulin G2 titers against MRP and SAO. Importantly, immunization with bacterin but not with MAP induced opsonizing antibody titers against the serotype 2 strain, and these antibody titers were found to correlate with protection. However, after absorption with a nonencapsulated isogenic mutant, the sera from bacterin-immunized piglets failed to facilitate neutrophil killing, indicating that antibodies directed against capsule may not have been essential for opsonophagocytosis. Furthermore, induction of opsonizing antibodies against serotype 9 was not detectable in the group receiving bacterin or in the group receiving the MAP vaccine. In agreement, protection against the heterologous serotype 9 strain was low in both groups. Thus, identification of an antigen protecting against these two important S. suis pathotypes remains an important goal of future studies.

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