Urine mRNA can predict kidney transplant rejection

Prompt diagnosis of acute kidney transplant rejection can improve the outcome of transplantation but it is dependent on the invasive procedure of allograft biopsy. In 29 March New England Journal of Medicine, researchers from Weill Medical College of Cornell University, New York describe a non-invasive diagnostic test for rejection based on measurement of mRNA encoding cytotoxic proteins in urinary cells.

Li et al measured mRNA encoding the cytotoxic proteins perforin and granzyme B in 24 urine specimens from 22 renal-allograft recipients with a biopsy-confirmed episode of acute rejection and in 127 samples from 63 recipients without rejection. They found that levels of mRNA for perforin and granzyme B were significantly higher in the urinary cells from the patients with acute rejection (p<0.001) (N Engl J Med 2001, 344:947-954).

Perforin and granzyme B cooperate to induce the death of target transplant cells and are present in...