SLE patients ( n = @ ) with stable , inactive disease , a serum @-hydroxyvitamin D ( @ -LSB- OH -RSB- D ) level @ ng/ml , an elevated anti-double-stranded DNA antibody level , and an IFN signature ( as determined by measuring the expression levels of @ IFN response genes ) were randomized into a @-week double-blind , placebo-controlled trial of vitamin D@ at doses of @,@ IU or @,@ IU .