Frontier Sciences: Taisei Kikuchi

Pioneering New Life Science with Parasitology and Bioinformatics

The primary focus of our research is worms, including nematodes and tapeworms. This group of organisms possesses highly developed muscular and nervous systems, and parasitic worms exhibit autonomous movement within the host organism. Consequently, the treatment of parasitic infections requires an approach distinct from that employed for bacterial and viral infections. At present, parasitic control is conducted by a small number of antiparasitic drugs. Therefore, the emergence of drug-resistant strains will be a critical threat to human health.

To address this threat of parasitic infection, a more comprehensive understanding of parasite biology is necessary. Parasites have evolved and developed the capacity to parasitize other animals throughout their evolutionary history. In nematodes, evolutionary transitions from a free-living to a parasitic lifestyle have occurred several times. C. elegans— a nematode widely recognized as a model organism—is a free-living species that feeds on bacteria in its natural habitat. In contrast, parasitic nematodes reside within the body of a mammalian host, which provides constant temperature, abundant nutrition, and elicits immune responses. Parasites have adapted to such extreme environments and have acquired various extraordinary capabilities through evolutionary processes. We are studying the mechanisms underlying their abilities using their evolutionary process as hints in order to develop new treatments for parasitic infectious diseases, as well as new life science technologies.

Longevity serves as a notable example of these capabilities. C. elegans exhibits a lifespan of only a few weeks; however, many parasitic worms survive for years. While C. elegans is frequently utilized in aging research, it has been demonstrated that adverse conditions, such as calorie restriction, are necessary for extended longevity. Conversely, parasites thrive in eutrophic environments and experience exceptionally long, productive lifespans. Therefore, investigation of these parasites may elucidate longevity mechanisms that could potentially lead to innovative discoveries. Parasites also possess a unique capability to modulate the host's immune system, a characteristic not observed in other pathogens. Elucidating this immunomodulatory mechanism could potentially lead to promising applications in the treatment of autoimmune diseases and allergies. Consequently, parasites represent a valuable resource for scientific investigation.

Notwithstanding their research potential, parasitology presents many challenges. For instance, many parasites have complex life cycles that necessitate animal hosts for completion. Replicating these life cycles within laboratory conditions proves challenging. Moreover, parasitological research does not progress as rapidly as studies involving other commonly utilized model organisms. To address these challenges, we are employing diverse research strategies, integrating advanced technologies and bioinformatics. Our current objective is to develop techniques for parasite manipulation and establish a novel life science paradigm centered on parasites.

These are model organisms we use in our laboratory. From left to right, a female adult of Strongyloides, C. elegans, and Sparganum proliferum, known as a “mysterious parasite.”

Laboratory members conducting experiments in the laboratory

Lab members play sports and refresh to develop ideas.