Scientists have discovered that a transplant drug called rapamycin can stimulate immune memory, which enables the immune system to respond faster and stronger to an infectious agent.
The study at the Emory Vaccine Center showed that rapamycin, given to transplant patients to suppress their immune system, can trigger the formation of memory CD8 T cells, enabling the immune system to respond faster upon secondary encounter.
Postdoctoral researcher Koichi Araki says that the new discovery will help improve the efficacy of vaccines with drugs that act similarly to rapamycin.
"Usually during the response to this virus, 90 percent of the CD8 T cells produced to fight an infection die after a few weeks," Nature magazine quoted Araki as saying.
"The memory cells are generated from the 10 percent that survive," he added.
The study showed that when mice infected with lymphocytic choriomeningitis virus (LCMV) were treated with rapamycin, more CD8 T survived.
Rapamycin's effects are "surprising and unexpected," said Araki.
For transplant patients, memory T cells can play a role in graft rejection, but they can also protect against infections.