Madridge Journal of Vaccines

ISSN: 2638-1966

International Conference on Vaccines

Feb 20-22, 2017, Baltimore, USA
Poster Session Abstracts
DOI: 10.18689/2638-1966.a1.003

One shot nipah virus like particle (NiVVLP) vaccine study

Pramila Walpita1* and Michael Holbrook2

1John A Burns School of Medicine at University of Hawaii at the Manoa Campus, USA
2National Institute of Allergy and Infectious Diseases, USA

Nipah virus (NiV) a highly lethal zoonotic paramyxovirus that was first recognized in Malaysia in 1998. Fruit bats (Pteropusspp) are the reservoir host of this virus. NiV infection caused a severe febrile encephalitis outbreak in humans who worked in close contact with pigs suffering from respiratory disease. The case fatality rate in humans was around 40%. Since 2001, the virus has re-emerged in Bangladesh and India where bats have been identified as the principal source of the virus and the case fatality ~60-100%. In this study, we have produced mammalian cell-derived native Nipah virus-like particles (NiV VLPs) composed of NiV G, F and M proteins. We have done a One Shot vaccine study at NIAID IRF facility. In vitro studies using transmission electron microscopy (TEM), the VLPs were structurally similar to authentic virus, functionally assembled and immuno-reactive. Western blot analysis showed that indeed the VLPs were composed of the G, F and M proteins. Hamsters vaccinated with adjuvantedNiV VLP survived.

Dr. Walpita earned her PhD from the University of London, England. Before joining UH, she was a Senior Research Scientist at Wyeth Vaccines, and more recently as Research Faculty at University of Texas Medical Branch. Her research interests include molecular biology, immunology, and pathogenesis of paramyxoviruses. Her current investigations are focused on developing virus-like particle (VLP)-based vaccine for two of the paramyxoviruses, Nipah virus and respiratory syncytial virus. She is pursuing studies to understand the biological and host response properties, and the ultrastructural make-up of varying VLPs with the aim of maximizing their therapeutic potential. An additional interest is in evaluating the molecular mechanisms of transcription and replication of viruses in the Paramyxovirinae subfamily.

Safety and protective efficacy of respiratory syncytial virus-like particles in a murine model

Micah Tepora*, Lisa M. Johns and Pramila Walpita

University of Hawaii at Manoa, USA

Respiratory syncytial virus (RSV) is the leading cause of severe respiratory infections in children worldwide, particularly bronchiolitis and pneumonia. Most children be infected with RSV by the time they reach the age of 2, with incidence rates higher during early months of infancy. It is estimated that in the United States, an average of about 58,000 children under the age of 5 are hospitalized due to RSV each year. To this day, there is still no licensed vaccine. In this study, we evaluated the safety and efficacy of monophosphoryl lipid A (MPLA)-adjuvanted RSV virus-like particles (RSV VLPs) that express the F and G surface proteins and the M matrix protein, in a murine model. F is a crucial protein in RSV vaccine development because it contains neutralizing epitopes that can be targeted by neutralizing antibodies. We conducted an in vivo analysis by immunizing BALB/c mice with diluent, RSV, MPLA-adjuvanted RSV VLPs, or non-adjuvanted RSV VLPs. Our results indicated that two intramuscular immunizations of the MPLA-adjuvanted RSV VLPs elicited a strong neutralizing antibody response. It also showed that immunization induced a RSV-specific IgG response and higher IgG2a levels compared to IgG1 which suggested a Th1-biased response. MPLA-adjuvanted RSV VLPs were also able to protect mice from RSV infection in the upper and lower respiratory tracts and the development of disease in the lungs based on the histopathology of the lungs. Our findings thus far lead us to conclude that using MPLA-adjuvanted RSV VLPs is a promising candidate for a RSV vaccine.

Micah Tepora has B.S. in Biological Sciences from Loyola University. Her research interest is infectious diseases. She has completed her M.S. Tropical Medicine from University of Hawaiʼi at Manoa.

Virus like particle vaccine expressing immune-modulating molecules

Jae-Min Song

Sungshin University, Republic of Korea

Virus-like particle (VLP) technology is an attractive platform for seasonal and pandemic influenza vaccine development. We showed that influenza VLPs can be modified using immune-modulating molecules such as GM-CSF to enhance VLP immunogenicity. For this study, chimeric VLPs were incorporated with GM-CSF, to enhance anti-influenza immunogenicity. Our results indicate that immunizations with the chimeric HA/GM-CSF VLPs elicited more potent and broadly neutralizing antibodies and neuraminidase-inhibiting antibodies in sera, and induced higher numbers of hemagglutinin-specific antibody-secreting cells and germinal center B cell subsets in splenoctyes. Immunization with the chimeric HA/GM-CSF VLPs induced stronger Th1 and Th2 cellular responses. The chimeric HA/GM-CSF VLPs showed heterlologous protective immunity. It is our hope that these findings provide useful information for developing multi-subtype influenza vaccines.

Development of a tissue culture origin vaccine for infectious Laryngotracheitis virus

Eun-Jung Choi*, Joong-Bok Lee, Seung-Yong Park, Chang-Seon Song, In-Soo Choi and Sang-Won Lee

Konkuk University, Republic of Korea

Infectious laryngotracheitis virus (ILTV), gallid herpesvirus 1 causes mild to severe upper respiratory disease in chickens. Live attenuated vaccines to control ILTV outbreaks have been developed using serial passages in chicken embryos (CEO) or tissue cultures (TCO) and the CEO vaccines have been using intensively worldwide. However, the CEO vaccines could acquire virulence through bird-to-bird passages, while the TCO vaccine could not be virulent. The TCO vaccine has not been registered in Korea.

In this study, we developed a TCO vaccine for ILTV with the Korean virulent field strain. Attenuation of the virulent field strain achieved through thirty times of serial passage of the parent stain in LMH cells. After serial passage, three times of pock purifications on chorioallantoic membrane were performed to select pocks that produced significantly smaller size than those of the parent strain.

A safety and efficacy test for two vaccine candidates were performed in specific-pathogen-free (SPF) birds. Fifty of six-week old SPF chickens were randomly assigned to five groups. Vaccination was performed via eye-drop method with TCO vaccine candidates and a commercial CEO vaccine (104 EID50/bird). The all birds were challenged at 2 weeks post vaccination. TCO vaccine candidates were safer than the commercial CEO vaccine. However, vaccine efficacy of the TCO vaccines was less than that of the commercial CEO vaccine. The developed TCO vaccine will allow alternative vaccine program, which can be applied variable conditions of poultry flocks in the Korean field.

Ms. Choi is a postgraduate student at College of Veterinary Medicine, Konkuk University, Seoul, South Korea.

Applying a radioprotective Mn2+ peptide complex (MDP) to the preparation of irradiated vaccines

Elena K. Gaidamakova1,2*, Vera Y. Matrosova1,2 and Michael J. Daly1

1Uniformed Services University of the Health Sciences (USUHS), USA
2Henry M. Jackson Foundation for the Advancement of Military Medicine, USA

Antioxidant Mn2+-peptide complexes accumulated in the extremely radiation-resistant bacterium Deinococcus radiodurans have a remarkable ability to protect and preserve the structure and functions of proteins exposed to megadoses of ionizing radiation, but they do not significantly protect nucleic acids (Daly et al., 2010).

Reconstituted D. radiodurans Mn2+-peptide complexes were shown to uncouple protein damage from DNA/RNA damage during supralethal exposures to gamma-radiation and applied to the preparation of irradiated vaccines. An ideal whole-organism vaccine lacks any infectivity, but retains all original epitope configurations needed to mount a protective immune response.

We rationally-designed the peptide component of Mn2+-peptide-orthophosphate complexes. One Mn2+-complex named MDP (Mn2+-DEHGTAVMLK-Pi) preserves antigenic structures in aqueous preparations of lethally-irradiated bacteriophage lambda, Venezuelan equine encephalitis virus (VEEV), and methicillin-resistant Staphylococcus aureus (MRSA). MDP-Irradiated vaccines for MRSA protected mice against MRSA skin infection.

This novel approach now has been successfully applied to other pathogens.

A Hepatitis B vaccine with a novel adjuvant SBP (HBsAg-binding protein)

Caixia Su*, Jingbo Wang, Rui Liu and Naishuo Zhu

Laboratory of Molecular Immunology, State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, China

In general, adjuvants play a very important role in vaccine. SBP is a HBsAg-binding protein which is screened out from human liver cDNA expression library. SBP has been confirmed to promote dendritic cells (DC) to phagocytize HBsAg more effectively and enhance the immunogenicity. These results suggest that SBP could be developed into a safe and promising adjuvant of Hepatitis B vaccine. In this study, the secretory SBP recombinant Pichia pastroris strain is cultured and fermentated, then SBP is purified from fermentation supernatant. The proportion of SBP in hepatitis B vaccine (Hansenula Polymorpha) is studied, finally a hepatitis B vaccine with the novel adjuvant SBP is manufactured and tested totally according to the requirements. All of the test items are qualified. Its safety, efficacy and stability are evaluated. The efficacy is significantly superior than the control vaccine. The safety and stability are qualified. The results indicate that the novel Hepatitis B vaccine is expected to overcome nonresponsiveness and hyporesponsiveness in a significant number of individuals, and to shorten the hepatitis B vaccine standard 3-dose vaccination regimen to 2-dose regimen, which need to be validated by clinical trials.

Engineering Doctor student in Biotechnology & Bio-Pharmcy, State key lab of genetic engineering, College of Life Sciences, Fudan University Shanghai 200433, PR China. Ms. Su has worked in R&D of diagnostic reagents, monoclonal antibodies, cytokines, vaccines and other biological products for over twenty years. She is focused on R&D hepatitis B, E and HPV vaccine in recent years. She led the team to have gotten 5 production licenses and 2 clinical approvals related to recombinant hepatitis B vaccine. Now HEV and HPV vaccines are in preclinical research.

A trivalent recombinant vaccine candidate against brucellosis

Sonal Gupta1*, Damini Singh1 and Rakesh Bhatnagar1

1School of Biotechnology, Jawaharlal Nehru University, New Delhi, India

Brucellosis is caused by Gram-negative bacteria of the genus Brucella, which infect different domestic and wild animals. So far, there is no available vaccine which is safe enough for humans. On this point, subunit recombinat vaccine has become the new breakthrough for combating brucellosis. The main goals of the present study include determining the prophylactic potential of a trivalent protein mixture consisting of BP26, Omp25 and L7/L12 ribosomal protein of Brucella abortus as a vaccine candidate against brucellosis. Merit of the Bp26 periplasmic protein is that it is conserved throughout the Brucella genus. It induces a strong Th2 response with mild increase in IFN-gamma levels. Ribosomal protein of Brucella L7/L12 is highly conserved protein in Brucella species and found to be highly immunodominant in the infected cattle. Also, Outer membrane protein 25 (Omp 25) is a highly conserved protein in Brucella sp. which is studied to be involved in virulence of Brucella. Therefore, the current work deals with the co immunization of mentioned 3 proteins following two different quantitative dose statistics for immunization in the mice; “40µg rL7/L12+40µg rBp26+30µg rOmp25 (Mixture 1)” and “20µg rL7/L12+20 µg rBp26+15 µg rOmp25 (Mixture 2)”. Here we show humoral immune response elicited by different mixtures, Mixture 2 (40 µg rL7/L12 + 40 µg rBp26 + 30 µg rOmp25) is similar to Mixture 1 (20 µg rL7/L12 +20 µg rBp26 + 15 µg rOmp25) in multivalent vaccine combination. It was observed that total IgG antibody response in tripartite vaccine was comparable to the mice immunized with Bp26, Omp25 and L7/L12 individually. Good Humoral and cellular immune response was elicited, suggested by higher IgG1 and IgG2 levels in mice immunized with trivalent protein combination.Thus, the simultaneous immunization with three antigens did not appear to diminish immune responses against its components.We also compare the cellular mediated immune response in trivalent vaccine immunized mice to individual protein immunized mice. Also, subunit vaccine is particularly safe for administration in humans and therefore can be used as a vaccine against human brucellosis. Therefore, this study suggests future application of this trivalent protein as an improved vaccine candidate against Brucella species infection.

Sonal Gupta she is working as a Ph.D research scholar at Jawaharlal Nehru University. She has completed her Masters in biotechnology from the same university. Before that she worked as a research scholar Her research interest is in cloning,Microbiology and Immunology.

A novel virus-like particle universal Influenza A vaccine candidate

Alex Ramirez

University College London / iQur - Flutcore, UK

Existing seasonal Influenza A virus (IAV) vaccines target highly mutable parts of the virus that vary between seasons. Vaccine design relies on predicting the predominant circulating influenza strains but when there is a mismatch between vaccine and circulating strains, efficacy is sub-optimal. Furthermore, current approaches provide no protection against newly emerging strains that may cause pandemics. One solution is to design vaccines that target conserved protein domains of influenza, which remain largely unchanged from year to year and are likely to be retained in new emergent variants. We present 2 virus like particles (VLP), built using the Tandem Core TM platform, as a universal group 1 IAV vaccine candidate. Tandem Core is based on the hepatitis B core protein which is known to be a highly immunogenic VLP and has the ability to confer immunogenic properties to proteins inserted into its structure. Immunisation with our VLPs, containing a total of 5 conserved antigens from matrix protein 2 (M2) and hemagglutinin stalk, leads to production of cross-reactive and protective antibodies. The polyclonal serum from immunised mice can bind group 1 and group 2 hemagglutinin types H1, H2, H3, H4, H5, H6, H7, H8, H9, H11, H12, H14, H15 and H16 and a conserved epitope on matrix protein 2 expressed on most strains of IAV. Vaccination with our VLP results in 100% protection from H1N1 heterologous and H3N2 heterosubtypic viral challenge, even at high viral challenge doses in mice. Serum transfer from vaccinated animals is sufficient to confer protection from influenza-associated illness in naïve mice. These data suggest that a tandem core based IAV vaccine might provide broad protection against common and emergent IAV strains causing seasonal and pandemic influenza in man.

Dr.Alex Ramirez is the Head of Immunology at iQur Ltd; a small London based biotech company specialising in vaccine technology and diagnostics. After receiving his PhD from Imperial College London, he completed a postdoctoral research fellowship at UMASS Medical School focusing on influenza vaccines and adjuvants. Previously he worked on the development of Men B vaccine (Bexsero) at Novartis AG and as scientific advisor to . During his time at iQur he has overseen the development of monoclonal antibodies to Hepatitis C virus and Pan-influenza and is currently involved in the development of their flagship Universal Influenza Vaccine VLP pro