Prospective Study of Rapamycin for the Treatment of SLE

43 SLE subjects and 56 healthy controls are being recruited. The study will last 1 year with 9 study visits from day 0 to day 360. The healthy controls only need to donate blood once. The study drug, sirolimus, is taken by mouth at a starting dose of 2mg/day. The dose is adjusted to achieve blood levels in the range of 6-15 ng/ml (the levels found to be effective for preventing organ rejections). Blood samples are obtained before taking sirolimus, every two weeks for the first month, then every three months until 1 year, and then three months later to check the effect of discontinuing rapamycin. Each SLE subject will be asked to provide up to 100 ml (20 teaspoons) of blood at each visit. The first 6 visits will take place within 3 months and the remaining 3 visits every 3 months. Routine laboratory work will be performed. Part of the blood drawn will be used for research and part will be used for routine lab work as part of standard of care. The non-routine laboratory studies include: 1. Assessment of mitochondrial function in intact T cells 2. Analysis of mTOR activity, FKBP12 expression, and global gene expression in lupus T cells. 3. Predictors of therapeutic efficacy of sirolimus in SLE. The study drug levels will be checked at every visit. The non-routine laboratory studies will be performed at Visits 0 and 8 for SLE subjects and at Visit 0 for the healthy control subjects. Healthy control subjects will be matched by age (a decade or less), gender, and ethnic origin. They will be recruited and analyzed only for immunobiological outcomes on the same day as lupus subjects. All subjects will sign an informed consent at visit 0. There is a separate informed consent for the main study, one for the SLE subjects and one for the Healthy Controls. The same subjects can participate in the genetic sub-study. They must sign another informed consent for the genetic sub-study, one for the SLE subjects and one for the Healthy Controls. There is no need for additional blood drawing since part of the blood drawn for the main study can be used for the genetic sub-study.