ChAdOx1 and MVA based vaccine candidates against MERS-CoV elicit neutralising antibodies and cellular immune responses in mice

Middle East respiratory syndrome (MERS) is an acute, high-mortality-rate, severe infectious disease caused by an emerging MERS coronavirus (MERS-CoV) that causes severe respiratory diseases. The continuous spread and great pandemic potential of MERS-CoV make it necessarily important to develop effective vaccines. We previously demonstrated that the application of Gram-positive enhancer matrix (GEM) particles as a bacterial vector displaying the MERS-CoV receptor-binding domain (RBD) is a very promising MERS vaccine candidate that is capable of producing potential neutralization antibodies. We have also used the rabies virus (RV) as a viral vector to design a recombinant vaccine by expressing the MERS-CoV S1 (spike) protein on the surface of the RV. In this study, we compared the immunological efficacy of the vaccine candidates in BALB/c mice in terms of the levels of humoral and cellular immune responses. The results show that the rabies virus vector-based vaccine can induce remarkably earlier antibody response and higher levels of cellular immunity than the GEM particles vector. However, the GEM particles vector-based vaccine candidate can induce remarkably higher antibody response, even at a very low dose of 1 µg. These results indicate that vaccines constructed using different vaccine vector platforms for the same pathogen have different rates and trends in humoral and cellular immune responses in the same animal model. This discovery not only provides more alternative vaccine development platforms for MERS-CoV vaccine development, but also provides a theoretical basis for our future selection of vaccine vector platforms for other specific pathogens.

Download Full-text

Induction of neutralising antibodies and cellular immune responses against SARS coronavirus by recombinant measles viruses

Vaccine ◽

10.1016/j.vaccine.2008.01.057 ◽

2008 ◽

Vol 26 (17) ◽

pp. 2164-2174 ◽

Cited By ~ 53

Author(s):

Matthias Liniger ◽

Armando Zuniga ◽

Azaibi Tamin ◽

Teldja N. Azzouz-Morin ◽

Marlyse Knuchel ◽

...

Keyword(s):

Immune Responses ◽

Sars Coronavirus ◽

Neutralising Antibodies ◽

Cellular Immune Responses ◽

Cellular Immune

Download Full-text

Safety and Immunogenicity of a Novel Recombinant Simian Adenovirus ChAdOx2 as a Vectored Vaccine

Vaccines ◽

10.3390/vaccines7020040 ◽

2019 ◽

Vol 7 (2) ◽

pp. 40 ◽

Cited By ~ 7

Author(s):

Pedro M. Folegatti ◽

Duncan Bellamy ◽

Rachel Roberts ◽

Jonathan Powlson ◽

Nick J. Edwards ◽

...

Keyword(s):

Immune Responses ◽

Mycobacterium Avium Subspecies Paratuberculosis ◽

Intracellular Pathogens ◽

Neutralising Antibodies ◽

Dose Escalation Study ◽

Cellular Immune Responses ◽

Simian Adenovirus ◽

Adenovirus Vectors ◽

Vectored Vaccine ◽

Cellular Immune

Adenovirus vectored vaccines are a highly effective strategy to induce cellular immune responses which are particularly effective against intracellular pathogens. Recombinant simian adenovirus vectors were developed to circumvent the limitations imposed by the use of human adenoviruses due to widespread seroprevalence of neutralising antibodies. We have constructed a replication deficient simian adenovirus-vectored vaccine (ChAdOx2) expressing 4 genes from the Mycobacterium avium subspecies paratuberculosis (AhpC, Gsd, p12 and mpa). Safety and T-cell immunogenicity results of the first clinical use of the ChAdOx2 vector are presented here. The trial was conducted using a ‘three-plus-three’ dose escalation study design. We demonstrate the vaccine is safe, well tolerated and immunogenic.

Download Full-text

Cationic Nanoparticle-Based Cancer Vaccines

Pharmaceutics ◽

10.3390/pharmaceutics13050596 ◽

2021 ◽

Vol 13 (5) ◽

pp. 596

Author(s):

Jeroen Heuts ◽

Wim Jiskoot ◽

Ferry Ossendorp ◽

Koen van der Maaden

Keyword(s):

Immune Responses ◽

Cancer Vaccines ◽

Molecular Mechanisms ◽

Vaccine Candidates ◽

Cellular Immune Responses ◽

Cell Induction ◽

Immunotherapy Of Cancer ◽

Cationic Nanoparticles ◽

Preclinical And Clinical Studies ◽

Cellular Immune

Cationic nanoparticles have been shown to be surprisingly effective as cancer vaccine vehicles in preclinical and clinical studies. Cationic nanoparticles deliver tumor-associated antigens to dendritic cells and induce immune activation, resulting in strong antigen-specific cellular immune responses, as shown for a wide variety of vaccine candidates. In this review, we discuss the relation between the cationic nature of nanoparticles and the efficacy of cancer immunotherapy. Multiple types of lipid- and polymer-based cationic nanoparticulate cancer vaccines with various antigen types (e.g., mRNA, DNA, peptides and proteins) and adjuvants are described. Furthermore, we focus on the types of cationic nanoparticles used for T-cell induction, especially in the context of therapeutic cancer vaccination. We discuss different cationic nanoparticulate vaccines, molecular mechanisms of adjuvanticity and biodistribution profiles upon administration via different routes. Finally, we discuss the perspectives of cationic nanoparticulate vaccines for improving immunotherapy of cancer.

Download Full-text