Rapamycin, like many anti-rejection drugs, suppresses immune T-cells. In this study, American and German researchers found the drug also inhibits the function and activation of dendritic cells.
These are cells that play a much earlier role in immune response because they're the first to identify foreign intruders in the body. The dendritic cells then present these intruders to other immune system cells, including T-cells.
Dendritic cells play an important role in conditions such as atherosclerosis and a number of autoimmune diseases, such as lupus, where dendritic cells create constant immune system responses.
The study also found Rapamycin disarms the trigger that allows the proliferation of dendritic cells. This trigger is a potent, naturally occurring growth factor. It also affects the proliferation of blood precursors and stem cells which, when unchecked, result in leukemia and other cancers.
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