Background Necrosis and apoptosis are different cell death mechanisms.
Necrosis is a pathological process that occurs after destruction of t
he cell membrane. Apoptosis is a DNA-dependent cell death mechanism, w
hich occurs under physiological and pathological conditions. Although
necrosis is a well-defined phenomenon in an acute graft rejection, the
occurrence and relevance of apoptosis during this process is largely
unknown. Methods. The enterocyte apoptosis rates in allografted (n=24)
and isografted (n=24) small intestines of the rat were compared using
the in situ end-labeling technique. Results. In situ end-labeling sho
wed a dramatically increased number of apoptotic enterocytes in allogr
afted small intestines, whereas increased labeling could not be observ
ed in isogeneic small intestinal grafts. Conclusions. We suggest that
graft rejection-associated apoptosis, in addition to necrosis, plays a
n important role in the course of organ failure, and that the degree o
f apoptosis represents another reliable indicator for the diagnosis an
d prognosis of transplant rejection.