When it comes to vaccinating their babies, bees don’t have a choice – they naturally immunise their offspring against specific diseases found in their environments, scientists say.
Researchers from Arizona State University, University of Helsinki, University of Jyvaskyla and Norwegian University of Life Sciences studied a bee blood protein called vitellogenin.
The scientists found that this protein plays a critical, but previously unknown role in providing bee babies protection against disease.
“The process by which bees transfer immunity to their babies was a big mystery until now. What we found is that it’s as simple as eating,” said Gro Amdam, a professor with ASU’s School of Life Sciences.
“Our amazing discovery was made possible because of 15 years of basic research on vitellogenin,” said Amdam, co-author of the research paper in the journal PLOS Pathogens.
In a honey bee colony, the queen rarely leaves the nest, so worker bees must bring food to her. Forager bees can pick up pathogens in the environment while gathering pollen and nectar.
Back in the hive, worker bees use this same pollen to create “royal jelly” – a food made just for the queen that incidentally contains bacteria from the outside environment.
After eating these bacteria, the pathogens are digested in the gut and transferred to the body cavity; there they are stored in the queen’s “fat body” – an organ similar to a liver.
Pieces of the bacteria are then bound to vitellogenin – a protein – and carried via blood to the developing eggs. Because of this, bee babies are “vaccinated” and their immune systems better prepared to fight diseases found in their environment once they are born.
Vitellogenin is the carrier of these immune-priming signals, something researchers did not know until now.
While bees vaccinate their babies against some diseases, many pathogens are deadly and the insects are unable to fight them. Now that researchers understand how bees vaccinate their babies, this opens the door to creating the first edible and natural vaccine for insects.
“We are patenting a way to produce a harmless vaccine, as well as how to cultivate the vaccines and introduce them to bee hives through a cocktail the bees would eat. They would then be able to stave off disease,” said co-author Dalial Freitak, a postdoctoral researcher with University of Helsinki.
Humans depend on bees and other pollinating insects for a huge portion of their food supply. Insect vaccines could play an important role in helping to combat colony collapse disorder, in addition to fighting a variety of diseases, researchers said.
This discovery could have far-reaching benefits for other species, as well as substantial, positive impacts on food production. All egg-laying species, including fish, poultry, reptiles, amphibians and insects, have vitellogenin in their bodies, researchers added.