Congratulations to PhD candidate Christopher Lopez, who successfully defended his thesis, "Studies on cellular and humoral immunity elicited by Influenza A virus infection and vaccination," on June 28, 2023. Chris is pictured with his mentor Kevin Legge, PhD (pictured on right).
Research
Influenza A virus (IAV) infections represent a serious public health threat worldwide due to seasonal epidemics and periodic pandemics. While vaccination represents an important and efficacious countermeasure to combat IAV, present vaccines predominately provide protection against matched strains of IAV and generate suboptimal protection against distinct unrelated IAV strains Thus, there has been substantial interest in developing a universal IAV vaccine capable of providing long-term, robust protection against multiple strains of IAV. One such candidate, a novel intranasally administered polyanhydride nanoparticle-based vaccine platform (IA
V-nanovax), has previously been shown to generate robust immunity and protection against subsequent homologous and heterosubtypic IAV infections in a murine model.
However, using the IAV-nanovax platform to incorporate disparate antigens from different stains of IAV to promote immunity and protection has not yet been examined as previous reports utilized IAV-nanovax encapsulating hemagglutinin (HA) and nucleoprotein (NP) derived from an H1N1 strain. As seasonal H3N2 IAVs co-circulate with H1N1, I investigated the cellular and humoral immunity induced, and protection afforded by IAV-nanovax encapsulating disparate antigens derived from IAV H3N2 (H3-nanovax) as well as examining the impact of combinatorial vaccination regimens utilizing both H1N1 and H3N2 antigens as is the case with current vaccines.
Through this work, I have made large bounds towards the development of a broad based IAV vaccine and furthered our understanding of determinants of immunity that define protection against IAV infection. I have found that certain antigenic targets may be better than others for promoting immunity and protection against IAV and that combinatorial vaccination regimens broaden this immunity/protection against multiple IAV subtypes. While many questions remain, this work can serve as the basis to the eventual development of a universal IAV vaccine with the potential to significantly mitigate the global burden of influenza virus and reduce it to a minor concern rather than a potential pandemic threat.
Background
Chris was born in Barrington, IL to Edward and Carla, 12 minutes following his (fraternal) twin brother Brandon, and like their twin-ness, this is where their similarities ended. While his twin and older sister Jamie enjoyed cartoons on Saturday mornings, Chris could be found watching "Wild Discovery" animal documentaries, sparking an early interest in science. His passion for microbiology later evolved from an unconventional source: history. He was fascinated learning about the medieval Bubonic Plague and the 1918 “Spanish Flu” pandemic and how something invisible to the naked eye could wreak global havoc. This curiosity cemented his ambition to become a scientist focused on infectious diseases.
Following high school, Chris went on to earn his Bachelor of Science in Microbiology from the University of Wisconsin–Madison, setting his sights on a Ph.D. and being one step closer to joining the fight against infectious disease. Deciding to continue his tour of the Big10, Chris joined the Ph.D. program in Microbiology and Immunology at The University of Iowa. While initially set on pursuing virology for his dissertation work, a fortuitous rotation in the lab of Dr. John Harty under the mentorship of then post-doc Dr. Scott Anthony sparked a passion for immunology. There, he delved into the study of resident memory T cells, learning how the best offense is a good defense and, to his dismay, that T cells are not shaped like a “T".
Chris's dedication to his research led him to the lab of Dr. Kevin Legge, where he merged his two passions, immunology and influenza viruses, anticipating the next pandemic had to be a respiratory virus like influenza. His research focused on host immune responses to respiratory infections and vaccinations, where he relished the opportunity to contribute to the development of vaccines against future pandemics that had been his catalyst so many years prior. It was not long after in 2020, when his work became especially relevant in the form of an unprecedented global pandemic, although he was wrong about the cause (he was close though).
Following graduate school, Chris hopes to continue his work researching infectious disease and developing novel therapies to fight existing and emerging pathogens, serving on the scientific front line to prevent the havoc previously wrought by pandemics like the Bubonic Plague, the Spanish Flu, and COVID-19.
In his free time, when he’s not engaging in his favorite past-time of napping, Chris can be found playing video games, reading, watching sports (Go Bears), or trying to schedule the next session of Dungeons & Dragons with friends sometime within the next 6 months.