HJAR Jan/Feb 2021

HEALTHCARE JOURNAL OF ARKANSAS I  JAN / FEB 2021 31 immunogenicity profiles. Current available studies have demonstrated the feasibility of formulating S protein, RBD domain, M protein and N protein with specific adju- vants. It should be noted that the development of a COVID-19 vaccine has been on a fast track. Thus far, four non-replicating viral vector vaccines, three inactivated vac- cines and two mRNA vaccines being un- der clinical phase III stage, with more are on the way (32). Though different types of adjuvants have been used in exploratory and pre-clinical studies (Tables 1–3), con- sidering the need for rapid deployment of COVID-19 vaccines for the pandemic, alum, which had been formulated in many other licensed vaccines, have been priori- tized (15, 16). In addition to the adjuvants described above, engineered nanomateri- als also shed light adjuvant development. It has been shown that physicochemical characteristics of aluminum oxyhydroxide could affect the optimal immunogenicity profiles of vaccine formulations (41, 83, 84). Moreover, a recent study has shown that an alum-stabilized Pickering emulsion (PAPE) showed robust RBD-specific IgG1 and Ig- G2a titers and a high level of inducing IFN- γ-secreting T cells in a COVID-19 vaccine. Additionally, it has been shown that a natu- ral and potent STING agonist encapsulated by pulmonary biomimetic liposomes trig- gered rapid humoral and cellular immune responses and exhibited a sustained cross- protection against influenza (76). However, more comprehensive mechanistic studies, including the nature of protective immune responses and screening of the various combinations of antigens and adjuvants, are needed for the successful development of a safe and effective COVID-19 vaccine. n Front. Immunol., 06 November 2020 | https://doi.org/10.3389/ fimmu.2020.589833 References available at URL above. © 2020 Liang, Zhu, Wang, Jing, Li, Xia, Sun, Yang, Zhang, Shi, Zeng and Sun. This is an open-access article distrib- uted under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the origi- nal publication Frontiers in Immunology is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms. 12 and older. The advisory committee is un- likely to recommend use in children under 18 until the vaccines have been evaluated in that group. Further, it is expected that the most susceptible people (health care workers and nursing home residents) will be the first in line to receive the vaccines as they become avail- able. How long do you expect to be work- ing on this particular project, and, if successful, what is the expected timetable for it to hit market? MCLACHLAN: We expect to be working on this particular project for the next six months to one year. If successful, we hope to move the research forward into a competitive fed- eral grant that would allow us to test these products in larger animal models and po- tentially humans. The move into the market is lengthy, despite the current warp-speed pandemic vaccine production. It is notable that the current first-generation vaccine tech- nology has been in the pipeline in one form or another for at least a decade. We predict that our vaccine product will potentially move faster than that, but it remains important to test any product for safety and efficacy, es- pecially in its early stages. We do expect that our vaccine adjuvants, as they proceed for- ward into potential clinical trials, will have the capacity to enhance future vaccines against the next potential pandemic. Do you think COVID-19 will change the way future vaccines are devel- oped? MORICI: We believe the plug-n-play vaccine platforms, such as mRNA and viral vectors, have shown tremendous promise to respond quickly to new or emerging viral threats. As such, we are likely to see huge investments in these technologies going forward. We do not yet know the limitations of these vaccines, such as whether they eliminate viral carriage or transmission or whether they provide long-term protection, because it is too soon to answer these questions. In addition, fur- ther improvements in stability of the mRNA vaccines could reduce the requirements for cold storage and enable broader global distribution. Nonetheless, these newer vac- cine technologies are a great addition to an ever-increasing diversity of licensed vaccine platforms. It is important to stress that while these specific mRNA COVID-19 vaccines are new, the mRNA technology itself used in these vaccines is not and that the rapid move into clinical trials was not truly as rapid as per- ceived by the public. Future vaccine design and implementation is unlikely to proceed at this pace, particularly against other types of pathogens (e.g., bacteria) or if they make use of new components that must be rigorously tested in animal models before small imple- mentation studies in humans. It is also nota- ble that the sheer amount of worldwide fund- ing for implementation of the first generation of COVID-19 vaccines is extraordinary and unlikely to be a routine process in the future. Once this pandemic passes, what is the next project your team would like to focus on? MORICI: Our team focuses on the devel- opment of next-generation vaccines by tai- loring vaccines with new adjuvants that can enhance protection in the mucosa, the major portal of entry for infectious agents. In ad- dition to a vaccine for SARS CoV-2 virus, we are currently working on vaccines to elimi- nate respiratory bacterial infections, such as those caused by Pseudomonas aeruginosa and Bordetella pertussis. In addition to these studies, we have recently turned our atten- tion to the global public health crisis caused by the opioid epidemic and are working with collaborators at Scripps Institute in La Jolla, CA to design an effective adjuvanted vaccine that can prevent overdose with heroin and fentanyl . n