Pump-Priming Project Awards - Round 9 Awardees

Mr Syed S Ahmed

CEO and Director
Techinvention Lifecare Pvt. Ltd
India

Collaborators:

Prof. Ray Borrow, Consultant Clinical Scientist, Head of UKHSA Meningococcal Reference Unit, Head of UKHSA Vaccine Evaluation Unit, UK Health Security Agency, UK

Summary

Neisseria meningitidis is a gram-negative diplococcus bacterium. Twelve serogroups have been identified, of which only six (A, B, C, W, X, and Y) are associated with invasive meningococcal disease (IMD).

N. meningitidis outbreaks occur, particularly in the meningitis belt of Sub-Saharan Africa, extending from Senegal in the west to Ethiopia in the east. Notable outbreaks include serogroup X in Ghana (2000), serogroup C in Niger (2015), serogroup C in Burkina Faso (2019), and currently serogroup C in Nigeria. Outbreaks of serogroup B disease have occurred in the 1980s in Cuba, Brazil, Norway, and in the 2000s in New Zealand. Meningococcal outbreaks of serogroup W during the Hajj pilgrimage have also been documented in 2000 and 2001. The World Health Organization (WHO) has classified meningitis caused by N. meningitidis under the category of epidemic and pandemic-prone diseases. Currently, there are two pentavalent vaccines, viz., ABCWY and ACWYX, licensed. Given the potential for future outbreaks involving any of the six prevalent serogroups (A, B, C, W, X, and Y), there is an urgent need for a hexavalent vaccine.

We are currently focusing on developing a hexavalent vaccine formulation designed to provide broad protection against N. meningitidis that combines polysaccharide conjugates from serogroups A, C, Y, W, and X with recombinant protein components, specifically factor H binding protein (fHbp) from serogroup B. Further, proof-of-concept (POC) studies will be conducted to assess its immunogenicity using the serum bactericidal antibody (SBA) assay. Our target populations include individuals in LMICs and travellers at risk.

Project Outcomes

Techinvention has developed a novel hexavalent meningococcal vaccine formulation (MenHexa) incorporating six clinically relevant N. meningitidis serogroups: A, B, C, Y, W, and X. The goal of this broad approach is to offer stronger and more comprehensive protection than currently available vaccines, which often cover fewer serogroups.

To evaluate the immunogenicity of the vaccine, a Good Laboratory Practice (GLP)-compliant proof-of-concept animal study was conducted in BALB/c mice (Mus musculus), a well-established immunological model. The study included four groups, each comprising 15 mice.

The strongest immune responses were seen in the group that received the full human vaccine dose with the adjuvant. These mice developed high levels of protective antibodies against serogroups A, C, and W, showing the vaccine can potentially offer strong protection. Responses to serogroups B and X were moderate. However, no immune response was shown to serogroup Y, suggesting need for further improvement.

These results are encouraging and show that the hexavalent vaccine has the potential to protect against multiple types of meningococcal bacteria. However, further refinement is needed to improve its effectiveness against all six targeted serogroups. Future work will focus on optimizing the serogroup Y, X and B components and testing serogroup B against multiple strains.

Professor Daniela Hozbor

Scientific Researcher and Head of Group
Ciencias Biológicas. Instituto de Biotecnología y Biología Molecular de la Facultad de Ciencias Exactas
de la Universidad Nacional de La Plata-CONICET Argentina

Collaborators:

Prof Andrew Gorringe, Scientific Leader, Vaccine Development and Evaluation Centre, UK Health Security Agency, UK

Dr Paul Lee Ho, Manager, Production Intelligence, BioIndustrial Center, Butantan Foundation, Brazil

Dr Milena Apetito Akamatsu, Director, Bacterial Vaccines Production Nucleous, BioIndustrial Center, Butantan Foundation, Brazil

Summary

Our research team has dedicated significant efforts to developing a vaccine prototype against Bordetella infections, particularly Bordetella pertussis, a causative agent of respiratory disease in humans. This prototype based on the outer membrane vesicles (OMVs) derived from the pathogen, has demonstrated promising safety and efficacy in preclinical trials (1–7). We have established a robust platform for obtaining and studying OMVs in the laboratory, identifying them not only as potent immunogens but also as effective adjuvants (8–11).

In this application, our focus is on overcoming a significant challenge in vaccine development: the transition from laboratory testing to clinical trials in humans. This critical step involves producing vaccine candidates at pilot scale under stringent Good Laboratory Practice (GLP) and Good Manufacturing Practice (GMP) conditions. We also propose designing protocols for clinical trials in humans and field tests for use in other animals.

Dr Young Chan Kim

Sir Henry Wellcome Fellow
University of Oxford
UK

Collaborators:

Professor Sir Andrew Pollard, Director of Oxford Vaccine Group, University of Oxford, UK

Professor Daniela Ferreira, Professor of Mucosal Immunity and Infection, University of Oxford, UK

Dr Sagida Bibi, Senior Postdoctoral Researcher, University of Oxford, UK

Dr Simon Clark, Scientific Leader, Vaccine Development Evaluation Centre / UK Health Security Agency, UK

Professor Sue Ann Clemens, Head of Oxford Latam Research Group, Oxford LATAM Research Group, Brazil

Summary

Plague, caused by the Yersinia pestis bacterium and transmitted by fleas, remains a global threat with sporadic but deadly outbreaks occurring in regions including Africa, China, Russia, particularly in the Democratic Republic of the Congo (DRC) and Madagascar. These outbreaks highlight the ongoing risk to public health. Researchers at the Oxford Vaccine Group (OVG) have been at the forefront of developing new vaccines against this ancient pathogen. We used a viral vector (ChAdOx1) carrying protective proteins from the plague bacterium and demonstrated excellent results in preventing plague in mouse models. This vaccine has successfully progressed to human studies, with Phase 1 clinical trials in the UK confirming excellent safety profiles and robust induction of antibody responses. Building on these successes, we are now developing a novel vaccine that uses mRNA technology. As part of this BactiVac project, we aim to test our vaccines as mucosal vaccines to induce strong mucosal responses. The goal is to not only protect against the lung-based (pneumonic) form of plague but also to understand the immune responses — humoral, mucosal, and cell-mediated immune responses that provide the protection. If successful, this research could be a significant step forward in the global fight against plague.

Project outcomes

Plague, a deadly disease caused by the bacterium Yersinia pestis, remains a global health concern. It spreads through flea bites and can cause devastating outbreaks, as seen in regions such as Madagascar and the Democratic Republic of Congo. There is also a significant concern that plague could be used as a biological weapon. Despite these threats, there is currently no licensed vaccine available for human use. Plague can cause a severe lung infection known as pneumonic plague. To effectively combat this, a vaccine should ideally trigger a strong immune response directly in the respiratory tract—the body's first line of defence against airborne germs. Standard injections into the muscle are good at creating a general, body-wide immune response but are less effective at stimulating this crucial "mucosal" immunity in the lungs.

To address this gap, our project investigated delivering a new plague vaccine candidate via intranasal (mucosal) vaccination. The goal was to see if the mucosal vaccination could generate a strong immune response in the lungs and effectively protect against airborne plague infection. We successfully demonstrated that administering the vaccine as an intranasal vaccination in mice induced a robust immune response, comparable to that of intramuscular injection. Most importantly, intranasal vaccination provided equivalent protection against inhaled Y. pestis bacteria in the lethal mouse challenge model. We also confirmed the presence of specific immune cells in the lung tissue, providing direct evidence of a localized mucosal defence. This project shows that our plague vaccine can be given intranasally to effectively protect against lung-based infection. This finding is a significant step forward in the global fight against plague, offering a promising new strategy for vaccination.

Ms Alexandra Sanchez-Martinez

PhD Student
University of Surrey
UK

Collaborators:

Professor Christine Rollier, Professor in Vaccinology, University of Surrey, UK

Dr Kishore Alugupalli, Associate Professor of Microbiology and Immunology, CEO of TurboVax Inc., Thomas Jefferson University, USA

Summary

Progressive functional and structural alterations in the immune system caused by age in humans result in heightened vulnerability to bacterial infections and diminished protective efficacy of conventional vaccines. Adjuvants are substances added to some vaccines to stimulate and enhance the immune response to induce a more effective immunisation. With adjuvants, the immune responses can be substantially more robust and long-lasting, especially for vaccines containing highly purified antigens with insufficient intrinsic immunostimulatory capabilities. Turbo, a novel vaccine adjuvant formulated with bacterial vaccines, shows promise in inducing long-lasting and highly protective immune responses across all ages in pre-clinical models, reducing the need for vaccine boosters for bacterial vaccines. We will assess the effect of ageing on the innate immune response of human cells to Turbo using adjuvant exploratory in vitro studies of antigen-presenting cells derived from older adults. We will further assess the immunogenicity of a Shigella dysenteriae type 1 vaccine candidate adjuvanted with Turbo using an aged animal model. This will enable us to propose the mechanism of action of adjuvants that can overcome immunosenescence and simultaneously support the development of a vaccine candidate against Shigella dysenteriae type 1, an antimicrobial-resistant bacteria particularly affecting older adults.

Project Outcomes

The project “Evaluation of Novel Adjuvants to Improve Bacterial Vaccines during Immunosenescence” evaluated the effect of the novel adjuvant Turbo (a TLR4 agonist) using in vitro models of macrophages, dendritic cells, and B cells from humans and mice during ageing. Additionally, the adjuvant capacity of Turbo in a Shigella dysenteriae 1 vaccine containing the IpaB and IpaD antigens was evaluated in young and aged mice. The TLR4 agonist-based adjuvant Turbo induces a higher release of TNF-α in macrophages during ageing, but a lower release in TNF-α dendritic cells from human and murine in vitro models. These results indicate that macrophages contribute to the inflammatory milieu observed during ageing (inflammageing). Our results also demonstrate the dysfunction of dendritic cells in ageing, which can result in lower vaccine responses. In addition, we compared the effect of Turbo with MPL-A ( commercial TLR4 agonist). Our findings suggest that Turbo induces higher levels of TNF-α in macrophages and dendritic cells compared to MPL-A. Moreover, Turbo promotes the upregulation of costimulatory molecules similarly in B cells from young and aged mice.

Dr Giuseppe Stefanetti

Assistant Professor
University of Urbino
Italy

Collaborator:

Professor Mariagrazia Pizza, Professor of Microbiology, Imperial College London, UK

Summary

Klebsiella pneumoniae (Kp) is a significant cause of hospital-acquired infections, leading to severe diseases such as pneumonia, sepsis, and urinary tract infections. This pathogen causes large-scale outbreaks in healthcare settings, with rapid transmission and severe clinical outcomes. The prevalence of the K64 capsular type, associated with the hyper-virulent sequence type ST147, has risen dramatically from 2% of reported genomes in 2012 to over 15% in recent years, underscoring the urgency for targeted vaccine development.

This project proposes to synthesize and compare multiple glycoconjugate vaccines targeting the K64 capsular polysaccharide (CPS). By conjugating K64 CPS with selected homologous carrier proteins, we aim to induce broader protective immunity, potentially offering cross-protection against different Kp serotypes. Mice will be immunized with the different glycoconjugates, and the induced immunogenicity evaluated by analyzing sera for antigen-specific antibody responses (IgG and IgM) and functional assays such as serum bactericidal activity and opsonophagocytic killing capacity against various Kp strains.

The expected outcomes include identifying the most effective carrier protein for the K64-based glycoconjugate, developing a vaccine that provides cross-protection against multiple serotypes, and demonstrating strong immunogenicity in animal models.

This project will also pave the way for future research, such as applying the developed methodology to other capsular types and pathogens, optimizing vaccine formulations, and advancing promising candidates to clinical trials in collaboration with LMIC partners and industry. The successful development of this vaccine could significantly reduce Kp infections in both hospital and community settings, particularly benefiting LMICs where the burden of such infections is high.

Project outcomes

Klebsiella pneumoniae is a leading Gram-negative cause of healthcare-associated infections (HAIs), implicated in pneumonia, bloodstream, and urinary tract infections worldwide. Surveillance and genomic studies consistently rank K. pneumoniae among the most prevalent nosocomial pathogens, with growing antimicrobial resistance burdens. Among capsular (K) types, K64 has repeatedly featured in high-risk, multidrug-resistant lineages such as ST147, driving hospital outbreaks and underscoring the rationale for capsular-antigen vaccination.

Because polysaccharides are T-independent antigens, they elicit suboptimal, poorly boosting responses in naïve hosts; covalent conjugation to protein converts the response to T-cell-dependent immunity with improved class switching, affinity maturation, and memory—principles validated by licensed conjugate vaccines. Building on this, we generated K64 glycoconjugates comprising purified K64 capsular polysaccharide (CPS) linked to carrier proteins. Alongside benchmark carriers (CRM197, ovalbumin), we evaluated homologous carriers derived from K. pneumoniae (i.e. OmpA, OmpA-displaying nanoparticle (OmpA-NP) and a DUF-family surface protein) to test whether adding conserved bacterial protein epitopes could broaden strain coverage beyond K64 alone. OmpA has independent support as a Klebsiella vaccine antigen, and nanoparticle display is a recognized strategy to enhance B-cell activation and breadth.

We extracted and purified K64 CPS, then optimized controlled sonication to balance chain length and conjugation efficiency. Conjugation employed 1-cyano-4-dimethylaminopyridinium tetrafluoroborate (CDAP) random chemistry, and products were characterized by orthogonal analytics: SDS-PAGE (high-molecular-weight, polydisperse smears diagnostic of CPS–protein coupling), HPLC-SEC, and sugar/protein colorimetry, with SEC and HIC for polishing.

In mice (prime/boost on days 0/15, alum-adjuvanted, 5 µg/mL sugar dose), all K64 conjugates elicited robust anti-K64 CPS IgG, with immune sera bound whole K64 K. pneumoniae and K64-poly-L-lysine in ELISA, indicating recognition of capsule also in its native context. Immune sera also bound to heterologous K1 and K2 strains by ELISA, with breadth most evident for DUF, and with some extent OmpA-NP, with other conjugates giving lower responses. Preliminary serum bactericidal assays (SBA) demonstrated complement-dependent killing, strongest for OVA glycoconjugate. Notably, DUF also showed a reproducible complement-dependent effect, consistent with its high ELISA titers, although further assays are needed to confirm the extent of functional protection. Opsonophagocytic assays (OPA) have been established with controls and will be applied to immune sera in follow-up studies.

Together, these findings provide proof-of-concept for a K64 conjugate vaccine and support the idea that homologous Klebsiella proteins, particularly DUF, may augment capsule immunogenicity and broaden strain coverage. The immediate next steps are to complete SBA/OPA assays and move toward efficacy testing in challenge models.

Dr Anurak Uchuwittayakul

Lecturer
Kasetsart University
Thailand

Collaborators:

Dr Kim Thompson, Principal Investigator, Aquaculture Research Group, Moredun Research Institute, UK

Dr Patcharapong Thangsunan, Research Scientist, Chiang Mai University, Thailand

Dr Thao Mai, Research Scientist, Moredun Research Institute, UK

Summary

The research focuses on developing an innovative oral transethosome vaccine to prevent Francisellosis, a bacterial disease caused by Francisella orientalis, in Tilapia (Oreochromis sp.). Francisellosis poses a significant threat to the aquaculture industry, leading to high mortality rates and severe economic losses. Outbreaks of this pathogen can decimate Tilapia populations, causing substantial financial damage to fish farmers due to the loss of stock and the costs associated with managing and containing the disease. The transethosome vaccine delivery system enhances the stability and bioavailability of the vaccine when administered orally, ensuring an effective immune response. By reducing the reliance on antibiotics, this vaccine addresses the growing concern of antimicrobial resistance (AMR) in aquaculture. Overuse of antibiotics in fish farming contributes to the emergence of resistant bacteria, posing risks to both aquatic life and human health. The study involves optimizing the vaccine formulation, conducting laboratory trial to assess its efficacy and safety, and providing recommendations for its implementation in aquaculture practices. With the advancement of oral vaccine delivery technology, the expected outcomes include reduced disease incidence, ensured vaccine safety, and seamless integration into standard practices. This vaccine can enhance the sustainability and resilience of Tilapia farming by decreasing antibiotic use, mitigating risks associated with antimicrobial resistance (AMR), and reducing economic losses due to disease outbreaks. Consequently, it can support global food security.

Project Outcomes

Emerging infectious diseases caused by Francisella orientalis (Fo) pose significant challenges to aquaculture. This study aimed to develop and evaluate a novel transethosome-based nanovaccine (T-FoBCFSVac) formulated with bacteriocin cell-free supernatant (BCFS) derived from F. orientalis. The characteristics of T-FoBCFSVac, including size, zeta potential and morphology, were analyzed using dynamic light scattering (DLS) and transmission electron microscope (TEM). The vaccine was then assessed for safety, protection and immune responses in tilapia vaccinated for 7 and 14 days, with sampling at week 8 post-vaccination following disease resistance analysis against F. orientalis. The T-FoBCFSVac vaccine exhibited uniform particle sizes (~100 nm) with a narrow polydispersity index (~0.24) and stable negative zeta potential (−55 to −58 mV). The optimized formulation preserved the structural integrity of bacteriocin and antigen components through mild ultrasonication processing. Immunological analyses revealed significantly elevated IgM titers, enhanced serum lysozyme activity, and upregulated immunoglobulin-related genes, including IgM. IgT and IgD and intestinal mucosal responses. Pathway enrichment analysis demonstrated progressive activation of innate and adaptive immune pathways, notably phagosome, cell adhesion molecules, cytokine–cytokine receptor interaction, ubiquitin-mediated proteolysis, RIG-l-like receptor signaling pathway, and intestinal immune network for Ig production. Protective efficacy studies showed significantly lower bacterial loads, improved survival rates (60–67.5%), and high relative percent survival (51.25–60.32%) in T-FoBCFSVac-treated fish compared to the controls. Importantly, no significant changes in blood biochemistry or tissue pathology were observed, which confirmed the nanovaccine’s safety and biocompatibility. These findings suggest that T-FoBCFSVac offers a robust and safe prophylactic strategy against F. orientalis, with potential applications for disease management in aquaculture.

Keywords: Transethosome-based nanovaccine, bacteriocin cell-free supernatant, Francisella orientalis, immunomodulation, intestinal mucosal immunity, oral vaccine, red tilapia.