Increased apoptosis dependent on caspase-3 activity in polymorphonuclear leukocytes from patients with cirrhosis and ascites.

BACKGROUND/AIMS: Patients with decompensated cirrhosis are prone to develop neutropenia. Although hypersplenism and increased clearance of polymorphonuclear leukocytes (PMN) in the spleen are thought to contribute to neutropenia in these patients, other factors cannot be excluded. The aim of the current study was to investigate whether the presence of increased PMN apoptosis could also contribute to the appearance of neutropenia in these patients.

METHODS

PMN were isolated by Ficoll-Hypaque gradient centrifugation from 17 patients with decompensated cirrhosis (CH group) and 13 patients with compensated chronic liver disease (CT group). PMN were incubated in RPMI 1640 medium at 37 degrees C in a 5% CO(2) atmosphere and viability and frequency of apoptosis were evaluated after 0, 10, 20 and 40 h of culture. Viability was determined by the MTT assay and apoptosis by microscopic examination of cell morphology (Diff-Quik staining), DNA fragmentation by agarose gel electrophoresis (DNA laddering) and caspase-3 activity by DVDE-p-nitroanilide cleavage.

RESULTS

Compared to CT patients, PMN isolated from CH patients exhibited a decreased PMN viability and a marked accelerated apoptosis as revealed by an increased number of condensed nuclei, increased DNA laddering and significantly higher caspase-3 activity.

CONCLUSIONS

These findings indicate that shortening of PMN survival via apoptosis may explain in part the neutropenia present in decompensated cirrhotic patients with ascites, thus favoring the development of bacterial infections in these patients.