The vaccines are based on human and chimpanzee adenoviruses that have been altered in the laboratory so that they are unable to replicate. In the current proof-of-principle study, the viruses were engineered to incorporate a gene from the rabies virus. Following oral administration of the vaccine, newborn mice developed antibodies that protected them from subsequent exposure to the rabies virus. By extension, the researchers say, the same vaccine strategy might also prove effective against other viral diseases, such as measles, viral respiratory infections, and viral diarrhea. A report on the study findings appears in the October 15 issue of the Journal of Immunology.
The potential significance of the new study lies in the effectiveness of the prototype vaccines in newborns. Although newborns are protected from most common viral infections immediately after birth by antibodies received from their mothers, these antibodies decline in the first weeks and months of life as the fledgling immune system grows in its capacity to generate its own antibody protections against viruses. Between the waning of maternal-antibody protection and the development of a fully functional immune system in the infant, a period of relatively poor defense against disease for infants is frequently seen. This is partly because the infant immune system is not yet sufficiently developed, but also because the maternal antibodies, while protecting the infant from inf
Contact: Franklin Hoke
The Wistar Institute