Researcher puts safety first in quest for vaccine
By Allison Tonini
When it comes to testing possible vaccines for deadly foal pneumonia, Dr. Stephen A. Hines, of Washington State University, makes animal safety his first priority. Dr. Hines’s commitment to humane research is evident in his recent Morris Animal Foundation–funded study, which explores effective immunization strategies against Rhodococcus equi.
“Our strategy has been to minimize the suffering of animals by using noninvasive methods to first study and define the mechanisms of protective immunity,” says Dr. Hines.
R. equiis a soil-based bacterial organism that is found in areas where lots of grazing animals live. Infected animals spread R. equi through their feces. Once on the ground, the bacterial organism thrives and multiplies. Hot, dry and dusty conditions allow R. equi to become airborne. Once inhaled, the bacterial organism can easily lead to rhodococcal pneumonia, a primary cause of death in foals.
During a foal’s first few months, it receives antibodies to R. equi from its mother’s milk. As it grows, a foal gradually develops its own antibodies and, more importantly, its own cellular immune response. Unfortunately, many young foals are exposed to the bacterial organism before their immunity is strong, and the result can be a serious threat to their health. The severity of the disease is one of the reasons Dr. Hines chose to research a potential vaccine.
“Rhodococcal pneumonia is such a complicated and devastating disease. We need to know more about it, so we can learn how to prevent it,” says Dr. Hines.
Although development of an effective vaccine would significantly improve prevention, Dr. Hines emphasizes that scientists must have strong evidence that a vaccine is likely to work before it is tested on live foals.
In his most recent Foundation-funded study, Dr. Hines specifically tested the use of hyperimmune plasma containing R. equi antibodies using blood cells from newborn foals and immune adult horses. Dr. Hines’s study confirmed that the use of plasma has positive effects in the prevention of rhodococcal pneumonia and that it can decrease the cell damage caused by an R. equi infection. Dr. Hines is excited to build on this study’s
“The next big barrier is figuring out how we should immunize newborn foals,” says Dr. Hines. “The oral route might be the key, so we will use these developments to explore an oral vaccine immunization.”
Posted by MAFon February 21, 2012. Permalink