What attributes does pollen have that make DoD consider it anything more than a seasonal menace to humans’ sinuses? To start with, the exterior of a pollen grain is a shell made of a naturally durable, non-allergenic polymer. The contents of the shell that actually contain the allergy-inducing plant proteins and fats can be cleaned out, rendering the shell itself neutral. The leftover space inside the shell could be filled with vaccines and delivered into the body through oral ingestion. The pollen shell’s natural toughness would help the vaccine survive conditions inside the body. The pollen could then pass through the intestinal lining to deliver vaccine.
The value of an orally consumed vaccine is that it is efficient, painless, can be self-administered and can induce both systemic and mucosal immune responses, thus enhancing protection. But why is pollen any better for this than a traditional pill? The body’s own processes often limit the effectiveness of pills. When patients ingest vaccines and other medications, stomach acids and digestive processes can degrade the medication. Because pollen shells are durable, however, they can potentially survive inside the body and safeguard a vaccine until it can be delivered. All this means that along with the traditional image of pollen as airborne particles that cause headaches and sneezing, pollen could also eventually be known as an edible vaccine delivery vehicle.