Day 1 :
Francis O Eko
Morehouse School of Medicine, USA
Keynote: How a phage lysis protein transformed Vibrio cholerae into a vaccine delivery platform
Time : 10:00-11:00 am
Francis Eko is currently working as a Professor of Microbiology and Immunology at Morehouse School of Medicine, Atlanta, USA. His expertise is in the development of vaccines and vaccine adjuvants. His current research involves development of self-adjuvant, cold-chain free vaccines against Chlamydia genital and respiratory infections and the effect of VCG-based adjuvants on immune responses to mucosal and systemic vaccines.
Statement of the Problem: Bacteriophage PhiX174 is an Escherichia coli-specific phage with a genome consisting of 11 genes. The phage encodes a single lysis gene E, the function of which is necessary and sufficient to induce lysis of E. coli. The resulting lysis protein E is a polypeptide of 91 amino acids and is devoid of any enzymatic activity. We previously showed that expression of the cloned lysis gene E causes lysis of Gram-negative bacteria. We have designed a versatile vaccine delivery platform based on the unique gene E-mediated lysis of Vibrio cholerae, which offers an exceptional opportunity to develop vaccines against different pathogens. Moreover, this platform is self-adjuvanting and capable of simultaneously delivering multiple vaccine antigens to the immune system. It also offers an attractive approach for developing combination vaccines, especially against diseases with epidemiological overlap. Here, we present data showing a utility of the VCG platform for induction of protective immunity even in the absence of external adjuvants.
Method: Groups of mice were Immunized Rectally (IR) or Intramuscularly (IM) with VCG expressing the Chlamydia trachomatis porin B and polymorphic membrane protein D proteins (rVCG-PmpD/PorB) or glycoprotein D from HSV-2 (rVCG-gD2) as antigen control. Vaccine efficacy was assessed by evaluating the intensity and duration of genital chlamydia shedding following intra vaginal challenge with live chlamydiae. Analysis of Variance (ANOVA) was used to compare differences between groups.
Findings: We demonstrated that both IM and IR immunization of mice with the rVCG vaccine elicited high levels of antigen-specific Th1 cell-mediated and humoral immune responses in mucosal and systemic tissues. Also, immunization reduced the length and intensity of genital chlamydial shedding following intra vaginal challenge with live chlamydiae, irrespective of route of vaccine administration.
Conclusion: These results highlight the potential of the VCG platform for eliciting immunity in the female genital tract via both mucosal and systemic delivery of antigens in the absence of external adjuvants.
- Vaccines and Immunization| Children Vaccine | Cancer Vaccine | DNA Vaccines
Location: ANA Crowne Plaza Osaka
Chandra Jyoti Hospital, India
Sunway University, Malaysia
Title: Efficacy and immunogenicity of a miRNA vaccine construct against Enterovirus 71
Pinn Tsin Isabel Yee has completed her Bachelor’s degree in Biochemistry from the National University of Singapore and dual Master’s degree in Life Sciences from Lancaster and Sunway University. She is currently pursuing her PhD in Biology with a Vice Chancellor Fellowship and PhD Studentship from Sunway University.
Enterovirus 71 (EV-A71) can cause mild hand, foot and mouth infections as well as fatal neurological complications. With concern about EV-A71 virulence, there is urgency for effective vaccines. Recent studies have reported novel vaccines incorporating microRNAs (miRNAs) that can regulate gene expression. A live attenuated vaccine strain was constructed by introducing two microRNA targets, let-7a and miR-124a, into the EV-A71 wild type genome to repress viral replication. The miRNA-bearing vaccine would not replicate in neuronal cells carrying the corresponding miRNA but could replicate in the gastrointestinal tract to act as immunogens. The pathogenicity of the miRNA vaccine strain was evaluated in RD, SHSY-5Y and NTERA-2 cell cultures by plaque counts, tissue culture infectious dose (TCID50) determinations and RNA copy numbers. Following transfection of the miRNA vaccine strain into the three cell lines, RD and SHSY-5Y showed minimal cytopathic effects, as compared to the NTERA-2 cells. The viral RNA copy number of the miRNA vaccine strain was much lower in RD (1.2×102) and SHSY-5Y cells (7.7×10) than the wild type RNA copy number of 3.9×104 and 5.8×104, in the respective cell lines. The TCID50 values indicate that the miRNA vaccine strain was attenuated as much as 6-fold when compared to the wild type. There was much reduction in plaque number (3.5×104 PFU/ml) when compared to the wild type (5.0×108 PFU/ml). Intra peritoneal administration of the miRNA vaccine construct in the murine model triggered a mixed Th1/Th2 response. The IgG subtype analysis of the miRNA antisera showed a strong IgG1 specific antibody response and a comparatively lower IgG2a, IgG2b and IgG3 response. As such, the miRNA strain is an attractive candidate to be developed as a live attenuated vaccine.
Toin University of Yokohama,Japan
Title: Proposal of artificial pandemic by infectious attenuated vaccine for reducing victims by wild type influenza pandemic
Yoshinori Hayakawa has completed his graduation from Tokyo University, Department of Applied Physics and PhD from Tokyo Institute of Technology. He has worked in Boron-Neutron-Therapy in Teikyo University and in Proton Radiation Beam Therapy in University of Tsukuba. He has measured first in the world acoustic pulse generated in the patient’s body treated by pulsed proton beam. He has worked as a Professor in Toin University of Yokohama, Japan. He has developed computer numerals and new abacus numerals for improving basic education to reduce poverty and also developed universal literacy alphabet as well. He is currently developing a plan to eliminate glacial period by reflecting sun light by mirrors on the moon surface and Lagrangian points of moon orbit.
New influenza pandemic might kill 300 million people in the world. Ordinary vaccines are too costly for many people in developing countries. Moreover vaccines are not available in early stages of pandemic. Ferret nasal mucosa is carcinized using carcinogen for easiness of incubation. Bird influenza virus is attenuated by reverse genetics. The virus is marked by green fluorescent protein. This attenuated virus is sprayed to many cultured cancer cell specimen incubated. In some specimen attenuated virus will mutated to increase in cancer cells, checked by green fluorescence. Then the virus is tested to infect ferret and then human volunteers without serious symptom. Virus with strongest virus titer to infect ferret is selected as seed virus of infectious attenuated live vaccine. The seed virus will be increased in incubated cancer cells by bioreactors all over the world and sprayed to vulnerable people, e.g. soldiers, students, people in slams, medical staffs and people engaged in lifeline. Drones may be used to enhance infection, spraying in slams and markets thin capsules including the live vaccine. Thin capsules are melted at human nasal mucous membrane. Thus basic immunity is gained by many people against dangerous virus. Artificial pandemic of dangerous virus as H7N9, H5N1 etc. are to be created serially with few years interval. Artificial pandemic should be initiated before wild type pandemic starts. One reason is to avoid reassortment (mixture) of virus RNA and another is to avoid clinical and social confusion. It should not overlap with influenza season. The number of victims seems to be less than 1000th of wild type pandemic. The calculation assumes the number of victims with infectious attenuated live vaccine is less than that of A/H1N1. Similar technique cannot be used for creating biological weapon as toxic virus kill cancer cells for incubation.
Timothi Van Mulder is a Clinical Affairs Manager and Quality Manager, responsible for the pre-clinical studies necessary for the development and optimization of Novosanis’ VAX-ID drug delivery devices. He also works in close collaboration with the technical D&E team to obtain CE labeling for the Novosanis’ devices. He has completed his Master’s degree in Science from the University of Antwerp. He is pursuing his PhD studies as Baekeland, working on the development of drug delivery devices suited for use in children and adolescents (PIDIC project funded by VLAIO, Belgium).
Background: Although Intra Muscular (IM) injection is still the most preferred method for vaccination, Intra Dermal (ID) delivery may have several advantages over IM and Sub Cutaneous (SC), including an improved immune response and antigen dose sparing effect. However use is limited due to the difficulty of the standard Mantoux technique. Difficulties encountered could be overcome by the use of alternative ID delivery systems. For the development of an ID device, VAX-IDTM, skin thickness of children and adults was measured through High-Frequency Ultrasound (HF-US) and performance of the device was evaluated in healthy subjects via a hepatitis B booster vaccination.
Method: Skin thickness in Caucasion volunteers aged 0 to 65 years was measured via HF-US at the proximal ventral and dorsal forearm (PVF and PDF), the deltoid region and lastly the medial part of the upper leg in children younger than 1 year. Both left and right body sites were included. Distances were measured from the skin surface to the dermal-hypodermal junction. In healthy adults two routes of administration were compared in four groups IM with HBVAXPRO 10 µg/1 ml or ID in the PDF according to the Mantoux technique with VAX-IDTM or with VAX-IDTM twice. For ID 0.11 cc (0.01 cc is overfill), was drawn from a vial containing HBVAXPRO 40 µg/1 ml. Immunogenicity and safety were followed-up at day 0, 14, 30 and 210.
Result: Skin measurements showed that a penetration depth of 0.7 mm is ideal for children while this is 1.0 mm for adults. After booster immunization in 48 adults, the ID groups showed a 3 fold higher antibody response at day 14 and 30 compared to IM group.
Conclusion: The investigated ID injection device VAX-IDTM proves to be a good alternative to offer ID vaccination.
Nelson Mandela African Institute of Science and Technology, Tanzania
Title: Diseases of goats and sheep presenting with respiratory signs: Limited biosecurity leaves vaccination as the best option for diseases control in developing countries
Andrew Chota is currently pursuing his PhD at Nelson Mandela Institution of Science and Technology. He has completed his Master’s degree in Molecular Biology and Biotechnology at Sokoine University of Agriculture, Tanzania. He is a Senior Veterinary Research Officer at the Ministry of Livestock and Fisheries positioned at the Tanzania Vaccine Institute. He has worked on Thermo Tolerant Newcastle Disease vaccine, Blackquarter and Anthrax vaccine in Tanzania. He is currently researching on diseases present with respiratory signs in sheep and goats under the Project for Enhancing Health and Productivity of Livestock (PEHPL).
Sheep and goats serve as sources of income and food security in many poor families in the developing countries. However, they are highly affected by diseases which present with respiratory signs. The mostly reported diseases in developing counties are contagious Caprine Pleuropneumonia (CCPP) and Peste Des Petits Ruminants (PPR) which are highly contagious Trans boundary Animal Diseases (TADs) and Mannheimiosis is the diseases caused by the normal commensals of the respiratory systems of ruminants, including sheep and goats. The disease occurs following impairment of the animal’s immune system due to stressful conditions or infection by viruses and mycoplasmosis. FAO’s guideline on the diagnostic and animal health services put a hierarchy from the central laboratories to provincial laboratories. However, routine diagnostics and animal health activities on field are performed by veterinary officers with the help of field staffs who lack facilities and clinical and postmortem examinations remain as the quick available diagnostic methods. These are not conclusive. Lack of diagnostic facilities results in partial and/or misdiagnosis which in turn causes poor control and eradication strategies. There is a need to elucidate the epidemiology of the CCPP, PPR and Mannheimiosis and levels of co-infections. This information will help in strategizing the control programs at national and regional levels.
Chandra Jyoti Hospital, India
Title: Typhoid disease and Vaccines Indian perspective
Rohit Agrawal has passion and expertise in vaccines and infectious diseases. He has been working in child healthcare since last 40 years. He is Convener of the APPA-TAG Immunization. He has been a Member of prestigious governmental policy making bodies like NTAGI and IEAG. In view of his distinguished services he has been awarded the ‘Outstanding Asia Pacific Pediatrician’ by the APPA Secretariat.
Introduction & Disease Burden:
Typhoid has a huge global burden with 21 million cases and over 200,000 deaths annually, the burden is more profound in developing world particularly in India [incidence 214.2/100,000].
Apart from huge burden and endemicity, three other major problems being: Poor hygienic conditions, sanitation, and over-crowding, Emergence of multi-drug resistant S-typhi and S-typhi H58clade and Changing scenario with children bellow 2 years getting equally affected.
The vaccines available in India are 2nd generation Vi- polysaccharide and 3rd generation Vi-polysaccharide conjugate vaccines
Vi-polysaccharide: poorly immunogenic, poor immunogenicity ,limited efficacy [60%]needs repeated doses, short duration protection and no effect < 2 years
Vi-Polysaccharide Conjugate Vaccines:
Currently two conjugate vaccines are available with 5 and 25 micrograms antigen. Various field trials for immunogenicity and efficacy showed more robust data in favor of 25 micrograms to the tune of 98.3% with 4 years follow-up studies. The vaccine is licensed for the age 6 months to 45 years. IAP-ACVIP recommends two doses at 9 months and 2 years with catch up vaccination up to 18 years. Need for a booster is a grey area due to scarcity of supporting data.
Conclusion: India being a highly endemic country for typhoid, with emerging MDR strains; certainly needs a cost-effective and highly efficacious vaccine which can be used on below two years of age. The new generation TCV vaccine is an ideal candidate
Beijing Academy of Agricultural and Forestry Sciences, China
Title: Avian Meta Pneumo Virus subgroup C attenuates the immune system of SPF chickens and enhances the susceptibility to Avibacterium paragallinarum
Jun Chu has his expertise and enthusiasm in animal disease and poultry infection. After years of training in laboratory and farm research, practice, teaching and experimentation, he has accumulated experience in the study of co-infection.
Statement of the Problem: Avian Meta Pneumo Virus (aMPV) and Avibacterium paragallinarum are frequently isolated from chickens with respiratory disease, especially Swollen Head Syndrome (SHS). However, the roles of these pathogens in co-infection remain unclear. We hypothesized that aMPV/C may enhance A. paragallinarum infection via suppression of host immunity.
Method: 21-days-old SPF chickens were inoculated with the aMPV/C JC strain or the A. paragallinarum Page serovar B strain/isolates and simultaneously vaccinated against Newcastle Disease Virus (NDV). The second experimental group of birds was inoculated with aMPV/C and A. paragallinarum simultaneously, inoculated with aMPV/C 3 days prior to A. paragallinarum infection, or inoculated with aMPV/C 3 days after A. paragallinarum infection; infection with aMPV/C or A. paragallinarum alone was also performed.
Findings: There was a significant decrease in the NDV antibody titer after aMPV/C infection. As for the second group, the body weights, immune organ indices, pathological changes, histopathological lesions, pathogenic loads, cellular and humoral immunity levels, the expression levels of IFNs, pro inflammatory cytokines, as well as anti-inflammatory cytokines were tested. Co-infection significantly reduced the body weight and thymus index of SPF chickens, significantly aggravating pathological changes and pathological damage. Simultaneously, prior infection with aMPV/C significantly decreased the cellular and humoral immunity, down-regulated the levels of the proinflammatory cytokine TNF-α and up-regulated the levels of the anti-inflammatory cytokine IL-4 in SPF chickens in response to A. paragallinarum.
Conclusion & Significance: In summary, aMPV/C infection suppresses the immune response by inhibiting cellular and humoral immune responses and altering the pro-/anti-inflammatory cytokine balance of SPF chickens, thereby enhancing the susceptibility of infected birds to A. paragallinarum.
China Agricultural University, China
Title: Combination of inactivated EBs,chistosan and VCG induces a better protection against avian Chlamydia psittaci infection
Chlamydia psittaci is a global infection in poultry farms. Avian species get infected through Chlamydia-contaminated aerosol or food. Clinically, C. psittaci infection in chicken leads to the airsacculitis and severe pneumonia. Our recent reports indicated C. psittaci aggravates immune suppression and facilities secondary infection, i.e. avian influenza virus, ORT and E. coli. Its prevalence exacerbates poultry industry due to lack of commercial vaccine. An idea vaccine can be achieved by modifying the delivery vehicle, route of immunization or by using nanoparticles as vaccine adjuvants. In the current study, combination of chitosan hydrogel, Vibrio cholerae Ghost (VCG) and inactivated Chlamydia EBs induced strong antigen-specific humoral and cellular immune responses. Furthermore, it may generate strong protection, alleviate lesions in the respiratory tract and accelerates Chlamydia clearance. Chickens were immunized intransasally (IN) by the combination of 1´106 IFU of the purified inactivated EBs, VCG and chitosan hydrogel while birds were given intranasally with purified live EBs or UV-inactivated EBs or CPG and chitosan hydrogel as the control groups. Antibody levels, lymphocyte proliferations, cytokines in lung lavage fluids were measured using commercial kits. Finally, birds were challenged intra-tracheally with live EBs of Chlamydia psittaci HJ strain. Gross lesions, bacterial shedding and bacterial load in tissues were determined as described previously with some modifications. Regarding C. psittaci-specific antibodies via intranasal way or intramuscular inoculation, VCG+EBs+chitosan group induced a significant increase in comparison with the EBs vaccine or chitosan hydrogel group from day 7 to day 28. As for proliferative responses and CD4+ lymphocytes, the VCG+EBs+chitosan group was superior to the CPG+EBs+chitosan group. Moreover, VCG+EBs+chitosan group generated significantly higher IL-2, IL-12 and IFN-γ in lungs than those of CPG+EBs+chitosan group. Post challenge, significantly decreasing air sac lesions and bacterial shedding were found in the VCG+EBs+chitosan compared with the live EBs group or the UV-inactivated EBs group. A dose-dependent protection was found in the combination with 25-50 mg of VCG, chitosan and UV-activated EBs post challenge. In conclusion, chickens immunized with chitosan carrier capsulated inactivated EBs and VCG displayed not only high cellular immune responses, but also a robust humoral response against C. psittaci with a significant decreasing chlamydial loads.