The late astronomer Carl Sagan looked to the sky and imagined billions upon billions of stars, but other scientists find similarly staggering numbers just below their feet or in trees, water, and air. Instead of stars, those scientists see insects. There are probably about 10 quintillion—a billion billion—insects on Earth, and they make up 5.5 or so million species. Some scientists see those billions of insects boosting bioprocessing.

A key driver behind that thinking emerged in 1983, when scientists virally infected cells from the alfalfa looper—a moth—to make interferon. Then in 2002, scientists at the U.S. National Institutes of Health described a similar insect-based method to produce recombinant adeno-associated viruses, which are commonly used in modern gene therapy.

The link between this history and modern bioprocessing arises largely from economics. Although bioprocessors produce many therapies from mammalian cells, scientists at the University of Michigan in Ann Arbor noted: “The high cost of using mammalian cells for manufacturing has motivated a constant search for alternative host platforms.” As they added: “Insect cells have begun to emerge as a promising candidate.”

That promise is becoming reality in today’s bioprocessing R&D and even in the marketplace. During the COVID-19 pandemic, for example, António Roldão, PhD, head of the cell-based vaccine development laboratory at the Instituto de Biologia Experimental e Tecnológica in Portugal, and his colleagues used insect cells to make SARS-CoV-2’s S protein. As these scientists reported, they produced a “highly glycosylated and complex S protein, without compromising its integrity and antigenicity, [that could] be included in a virosome-based COVID-19 vaccine candidate.”

Plus, some insect-produced products are already available. For example, cells from the fall armyworm, a moth relative, are used in the production of Sanofi’s Flublok Quadrivalent influenza vaccine.

Bioprocessing scientists will continue to explore new ways—sometimes with moth cells, other times with mammalian ones—to make medicines. Maybe insect cells won’t take over bioprocessing, but they certainly give scientists lots of opportunities to consider—maybe not billions, but it could be millions.