(rapamycin) n. an immunosuppressant drug used to prevent rejection in kidney transplantation. Sirolimus was first discovered as a product of the bacterium Streptomyces hygroscopicus in a soil sample from Rapa Nui (the Polynesian name for Easter Island), hence the alternative name. It blocks the activation of B and T lymphocytes by *interleukin 2 (IL-2).
Health Encyclopedia