A group of researchers has developed a new vaccine that can be taken orally and absorbed through the intestinal mucous membrane, a breakthrough expected to be used for the next generation of vaccines to tackle AIDS and influenza.
The study group was headed by Prof. Hiroshi Kiyono of Tokyo University's Institute of Medical Science. Kiyono, a specialist in mucosal immunology, focused his research on a cell that triggers the mucous membrane's immune system.
He combined a protein that targets the cell with a vaccine and tested it on a mouse.
The combined vaccine worked effectively to prevent disease agents.
In the intestines and pharynx, M cells absorb viruses, bacteria and allergens and help the immune system work.
However, because there are relatively few such cells, it has been difficult to use them for immunological purposes, with the polio vaccine among the few that can be taken orally.
However, the group found a special protein that only reacts to the M cell from the mouse's mucous membrane.
Researchers combined the protein with vaccines for tetanus and botulinum and gave them to the mouse orally. They found that the vaccine stimulated the mouse's immune system to produce enough antibodies to give it effective protection against disease.
They then gave the new vaccine to another mouse and injected it with 10,000 times the lethal dose of botulinum. The mouse survived, proving the effectiveness of the new vaccine.