“That impulse has shaped a research journey spanning pharmacology, immunology, infectious diseases, and experimental model development,” says Prof. Nainu. Over the years, he has contributed to a body of work that moves between mechanistic laboratory research and broader public health questions, always with a focus on relevance. His work—spanning host–pathogen interactions, repurposed drugs, or global disease burden analyses—operates at the intersection of biological insight and real-world needs.
“My academic journey has taken me across several countries and research environments, each of which has shaped my scientific perspective,” shares Prof. Nainu. After completing his bachelor’s degree in pharmacy from the Faculty of Pharmacy at Hasanuddin University, he went on to pursue a master’s degree in biomedical sciences at James Cook University in Australia—the same alma mater as the Rector and Professor Halmar—before continuing to a Ph.D. in Pharmaceutical Sciences at Kanazawa University in Japan, nurturing his focus on biomedical research. His engagement with biomedical research deepened further with postdoctoral training and visiting researcher positions at esteemed institutions like The University of Queensland, The University of Manchester, The University of Cambridge, Duke-NUS Medical School, The University of New South Wales, and Kyoto University. “These experiences,” he describes, “were not only about learning new techniques, but about adapting to different scientific cultures, thinking critically and learning to collaborate across disciplines.”
A turning point: Drosophila melanogaster as a model system
After completing his Ph.D., the choice of a fruit fly as an in vivo model organism turned out to be a defining moment in his career. Explaining further, Prof. Nainu adds, “What may once have seemed like a bold shift went on to become a defining direction, opening new ways to study host–pathogen interactions efficiently, in a scalable manner.”
That decision speaks about one of the central themes of his research—the careful development and use of experimental models that are both reproducible and biologically informative.
But one may wonder why? In vivo systems (like D. melanogaster, commonly known as the fruit fly) are powerful, precisely because they preserve the complexity of living biology. But that complexity also creates variability. Sharing his experiences, Prof. Nainu states, “One of the key issues is the sensitivity of experimental outcomes to changes in environment, handling procedures, and genetic background, making reproducibility a constant challenge.” This was a key learning for him, highlighting the need to build reproducibility into every stage of the research process.
“The limitations of model organisms,” he argues, “must be confronted directly.” No model fully recapitulates human physiology, and translational relevance depends not on pretending otherwise, but on understanding exactly what a model can and cannot reveal. This is where Drosophila has proved especially valuable in his work. Despite its simplicity and evolutionary distance from humans, fruit fly retains many evolutionary conserved innate immune pathways, including signaling pathways like Toll and Imd, which makes it highly relevant for studying host–pathogen interactions.
Compared with traditional mammalian models, Drosophila offers clear practical advantages. Its short life cycle, genetic tractability, and low maintenance requirements enable rapid experimentation and large-scale studies that would be far slower and more resource-intensive in mammals. For Prof. Nainu, this efficiency helped shape both his research questions and his research output. The model encouraged him to focus on core biological mechanisms and to design experiments that are precise, scalable, and hypothesis driven.
In his opinion, however, Drosophila is not a replacement for mammalian systems, but as a complementary platform. “Its strength lies in helping researchers uncover robust and biologically meaningful insights that can then be interpreted in light of higher-order models and clinical evidence. In that sense, the fruit fly becomes more than a convenient laboratory organism. It becomes a strategic tool for asking sharper questions about human disease,” asserts Prof. Nainu.
Crossing boundaries in disease research and drug discovery
Prof. Nainu’s broader research philosophy is also rooted in an integrative approach, underlying the principles of reproducibility and translational evidence. Working across pharmacology, immunology, and virology, he views interdisciplinary science not as an optional enhancement but as an essential component for understanding disease mechanisms and developing therapeutic interventions. “Evaluating a therapeutic mechanism requires more than knowing whether it affects a microbe. It also requires understanding how host responses, inflammatory pathways, and disease outcomes are shaped,” he explains.
This perspective is especially important in his work on drug repurposing. At a time when antimicrobial resistance continues to erode the effectiveness of conventional antibiotics, repurposing existing drugs offers a pragmatic alternative. Drugs with known safety profiles can potentially be redirected toward urgent therapeutic challenges more swiftly than entirely new compounds can be developed. But for Prof. Nainu, the importance of repurposing goes beyond that, as it also challenges the traditional understanding of therapeutics.
His work on aspirin and metformin reflects this shift. “Metformin, long known as an antidiabetic drug, may also influence host–pathogen interactions in ways that extend beyond its conventional use. Rather than functioning only as a direct antibacterial agent, it appears capable of modulating biological processes that may alter infection outcomes. That possibility points toward a broader view in which a drug’s full biological activity, including its effects on host pathways, may hold untapped therapeutic potential,” explains Prof. Nainu.
Bridging mechanistic research and global health
Alongside his laboratory research, Prof. Nainu has also contributed to large-scale global health projects, such as the Global Burden of Disease Study. Far from being separated from his mechanistic work, he sees such collaborations as complementary. Global health collaborations help to identify where disease burdens are heaviest and where unmet needs remain most urgent. Laboratory research, in turn, helps explain the biological mechanisms behind those patterns and contributes to the search for solutions.
This connection is particularly evident in his recent work related to chronic respiratory disease in Asia. The findings point to an uneven but substantial regional burden, shaped in large part by modifiable risks such as smoking, ambient particulate pollution, and household air pollution from solid fuels. Prof. Nainu asserts, “Actionable priorities should involve stronger tobacco control, cleaner household energy, improved ventilation, earlier diagnosis, and more equitable access to long-term care.”
These population-level concerns also resonate with his previous mechanistic research on tobacco smoke exposure. In that study, he had explored how tobacco smoke extracts affected not only the host, but also bacterial pathogens’ genetics, revealing that environmental exposures may shape both sides of the host–microbe relationship. Even when the downstream effects on virulence are complex, such findings highlight the layered biological interactions that still need to be more fully understood.
Across all of this work, one theme remains constant, and that is ‘real-world relevance.’ Prof. Nainu’s research is driven by the conviction that strong science must do more than generate data. “It must ask useful questions, build reliable systems, and remain responsive to the health challenges that matter most,” he adds.
Shaped by support: A nurturing ecosystem at Hasanuddin University
Reflecting on his association with Hasanuddin University, Prof. Nainu regards it as an important part of his scientific journey. He credits the supportive academic environment provided by the university, manifesting as access to laboratory facilities, research funding, mentoring opportunities, and support for international collaborations, which he attributes to his growth as an independent researcher. Just as important has been the opportunity to work closely with students, especially in projects involving Drosophila models and drug repurposing, helping to build a dynamic and productive research team. “Hasanuddin University provides a solid and continually developing platform for researchers who are motivated to pursue impactful and globally connected scientific work,” he adds.
Flying high: The journey ahead
Looking ahead, Prof. Nainu hopes to expand interdisciplinary work at the interface of infectious diseases, host–pathogen interactions, and therapeutic discovery, while strengthening the translational dimension of his research and deepening his engagement with global health initiatives. “Continued institutional support, particularly in funding, infrastructure development, and facilitation of international partnerships, will be critical in achieving these goals,” he notes.
