Inoculating Hope: Celebrating Innovation on World Vaccine Day & HIV Vaccine Awareness Day

melody.chang

On May 14, 1796 the world’s 1^st vaccine was successfully generated and we annually celebrate that milestone on World Vaccine Day. However, despite a number of lifesaving vaccines, there is still no known vaccine that can be used to stem the flow of the HIV infection. To raise awareness of the need for an HIV vaccine, May 18 is recognized every year as HIV Vaccine Awareness Day, or World AIDS Vaccine Day. These two vaccine days offer us a moment to reflect on the historic and scientific milestones that have saved countless lives and recognize the ongoing efforts in vaccine development.

The Rampage of Viruses vs. the Legend of Vaccines

Vaccines are one of the greatest tools we have to protect human health. The story of vaccines begins with the pioneering work of Edward Jenner in the late 18th century. Jenner's discovery that inoculation with cowpox could protect against smallpox laid the foundation of the field of immunization. Since then, vaccines have been responsible for reduction and eradication of deadly diseases caused by pathogens such as viruses and bacteria. The COVID-19 pandemic caused by the novel coronavirus SARS-CoV-2 quickly spread globally in 2020. Vaccines once again become a powerful weapon, reducing an estimated 63% of deaths caused by COVID-19 globally (estimated 19.8 million deaths prevented) during the first year of COVID‐19 vaccinations.

History has shown us the devastating impact of viral diseases and the remarkable role vaccines play in safeguarding humanity.

Technological Advancements in Vaccine Development

Vaccine technology has evolved dramatically in the past 200 years. The process of creating new vaccines and improving existing ones is being accelerated. Traditional vaccines often use weakened or inactivated forms of a pathogen to stimulate an immune response. Meanwhile, newer vaccines have started to employ parts of a virus or bacteria, such as proteins or polysaccharides, to achieve the same goal without the risk of causing disease.

Here are some of the key areas where technology has made an impact.

Recombinant Protein Subunit Vaccines

This kind of vaccine contains only a fragment of a pathogen, typically a protein or peptide capable of triggering an immune response. These fragments, known as antigens, are produced using recombinant DNA technology. Genetic code for a vaccine antigen is inserted into a vector, such as a plasmid, which is then introduced into a production cell line generally composed of bacterial or yeast cells. These cells act as bio-factories and produce large quantities of the antigen. Advances in protein engineering and cell culture systems have improved the development of these vaccines.

DNA Vaccines

DNA vaccines directly introduce a DNA plasmid containing the antigen-coding gene into the body. Cells then use this DNA to produce the antigen and stimulate an immune response. DNA vaccines are still a developing technology but hold promise for rapid development and potential cost savings.

mRNA Vaccines

The development of mRNA vaccines represents a revolutionary shift in vaccine technology. These vaccines, such as Pfizer-BioNTech and Moderna’s COVID-19 vaccines, use messenger RNA to instruct the vaccine recipient’s cells to produce a protein that is part of the virus, prompting an immune response. mRNA vaccines can be developed and manufactured quickly compared to traditional vaccines.

Viral Vector Vaccines

Viral vector vaccines, such as the Oxford-AstraZeneca and Johnson & Johnson COVID-19 vaccines (now discontinued), use a virus that has been engineered to be harmless to carry DNA or RNA of the pathogen’s antigen into cells. Then the antigen is expressed to elicit an immune response. This platform allows for relatively rapid development and can be adapted for different diseases.

Vaccine Delivery Systems

Lipid nanoparticles (LNP) have become a crucial component in the field of vaccine delivery. LNPs are tiny, engineered particles that can encapsulate nucleic acids, such as mRNA, and protect them from degradation while facilitating their delivery into host cells. These particles are composed of various lipids that can form a spherical structure, with the mRNA encapsulated within.

The success of LNP-encapsulated mRNA vaccines against COVID-19 has highlighted the potential of this technology for other infectious diseases and even beyond, such as in cancer treatment where personalized mRNA vaccines could potentially be developed to target tumor-specific antigens.

Computational Biology

Bioinformatics and computational biology allow for rapid identification of potential antigens and vaccine design. This was particularly evident in the rapid development of COVID-19 vaccines, when the viral genome was quickly sequenced and shared globally.

GenScript's Contribution to Vaccine Development

Infectious Disease

When infections from SARS-CoV-2 radiated globally, researchers scrambled to develop a vaccine. GenScript, as a leading biotech company, made it a mission to support the development of a COVID-19 vaccine. After the viral genome sequence was released, vaccine developers from around the world requested synthesized genes, proteins and peptides. Novavax ordered the full-length gene for SARS-CoV-2’s spike protein. Even today, constructing a full-length gene like the spike gene takes quality engineering that is difficult to achieve, and for Novavax, every day mattered. GenScript synthesized the SARS-CoV-2 spike gene and delivered it in just three days. “That was remarkable,” says Gregory Glenn, the company’s president of research and development in response to receiving his full-length gene in such a short time.

Cancer Treatment

Pancreatic ductal adenocarcinoma (PDAC) has surpassed breast cancer as the third leading cause of cancer-related death in the United States. A groundbreaking study on personalized mRNA vaccines for PDAC has shown promising results. The vaccines are safe, stimulate T-cell responses, and exhibit persistence and effectiveness. Clinical outcomes demonstrate improved survival and reduced recurrence.

This study conducted extensive cellular experiments to investigate the specificity of T-cell clones for neoantigen peptides. GenScript is also honored to be involved and provide neoantigen peptide synthesis service in this research.

Summary

World Vaccine Day and HIV Vaccine Awareness Day are not just about commemorating past successes but also looking forward to future innovations. The development of new vaccine technologies continues to revolutionize the field and offers hope in the fight against infectious diseases as well as cancer treatment and personalized medicine. The scientific community's efforts to develop safe and effective vaccines will continue to contribute towards improvements in global health and well-being.

References:

[1] Lives saved by COVID‐19 vaccines. J Paediatric Child Health. 2022 Sep 20: 10.1111/jpc.16213.

[2] Saleh A, Qamar S, Tekin A, et al. (July 26, 2021) Vaccine Development Throughout History. Cureus 13(7): e16635. DOI 10.7759/cureus.16635.

[3] Rojas, L.A., Sethna, Z., Soares, K.C. et al. Personalized RNA neoantigen vaccines stimulate T cells in pancreatic cancer. Nature (2023). https://doi.org/10.1038/s41586-023-06063-y.