Spontaneous blastogenesis as a monitor of renal allograft rejection.

Spontaneous blastogenesis (SB) of peripheral blood lymphocytes was studied by determining protein synthesis using 3H-leucine to establish an immunological monitoring method after renal transplantation. In acute rejection, the SB level was twice as high as those in ATN and in the quiescent state. A rise in SB level comparable to that in rejection was observed in patients with infection. The SB level was continuously determined postoperatively in eight patients undergoing renal transplantation. Of the eight patients, three showed acute rejection four times in total. Elevation of SB level was simultaneously observed at each rejection episode. Rejection was not noted in any of the other five patients. False positive elevation of SB level was observed five times. The cause of the false positive changes was unknown in three cases and due to infection in two cases. Elevation of SB level is considered to be nonspecific and represents total lymphocyte activity. Due to its simple procedure and quick results, this method should provide a useful clinical parameter of rejection.