High Five Cell Line Improves Human Health

Most people who encounter the cabbage looper, a green caterpillar pest that dines on vegetable crops, would call it a pest and leave it at that. But thanks in part to research at BTI, these humble garden nuisances have transcended their bad reputation by helping lead to the creation of a life-saving vaccine.

This unlikely connection came about thanks to insect virologist and BTI (now) Emeritus scientist Bob Granados, who was working at the time on developing genetically-engineered baculoviruses–a specific family of rod-shaped viruses that typically infect invertebrates–for biocontrol of insect pests in crops. In order to grow the viruses, Granados needed a reliable host. By 1994, he settled on none other than the cabbage looper–using cells from the insect as virus incubators. These cells were so effective at producing the key proteins necessary for biocontrol research, the line was patented, and became a standard tool in the Granados and other research labs–nicknamed the “High Five” cell line.

Prior to this work, medical researchers began to investigate the feasibility of developing vaccines for Human Papilloma Virus (HPV), the most common sexually-transmitted disease that infects 14 million people every year. With persistent infection, the virus can lead to cervical and other cancers.

Scientists looked into using baculoviruses as a safe method for engineering HPV-neutralizing antigens which could be given as a vaccine. And, like Granados, they needed a stable host cell to grow their engineered baculoviruses in. “A lot of labs were looking for a good insect line to do this work,” said Paul Debbie, Director of Technology Transfer and Licensing at BTI. “They needed it to be stable, and able to produce a lot of protein–so Bob did some work to see if the High Five cell line could work for this, and it was.”

Through research collaborations with scientists at other universities and institutes, and through partnering with drug development companies MedImmune and GlaxoSmithkline, Granados’ High Five cabbage looper cell line became the vehicle for producing the HPV vaccine known as Cervarix, one of the only two HPV vaccines available today.

Debbie says that this achievement would never have been possible without the diligent scientific research done by Granados and his counterparts. “There were all these basic science projects converging to one very useful therapeutic that saves lives,” said Debbie. “With basic research, one doesn’t necessarily know what the final outcome is going to be–it takes this very circuitous route, and it can end up having a big impact.”