[Study of apoptosis of peripheral blood mononuclear cells in patients with multiple organ dysfunction syndrome]

To study apoptosis of peripheral blood mononuclear cells (PBMCs) in patients with multiple organ dysfunction syndrome (MODS) and its associated gene Bcl-2 and p53 expression.

Twenty-five patients with MODS and 18 healthy volunteers were enrolled for the study. Flow cytometry assay, electron microscopy, acridine orange-ethidium bromide staining and fluorescence microscopy, DNA agarose gel electrophoresis were used to identify and quantify apoptosis of PBMCs. Reverse transcription-polymerase chain reaction (RT-PCR) was used to quantify Bcl-2 mRNA and p53 mRNA expression.

Typical morphological features of apoptotic PBMCs were observed in the patients. The apoptosis rate in MODS group was (25.4+/-9.2)%, and it was higher than that of control group (15.9+/-6.8)% (P<0.01). The number of apoptotic cells was (1.040+/-0.096)/high power field in MODS group, and it was higher than that in control group (0.235+/-0.028)/high power field (P<0.05). Bcl-2 mRNA expression of PBMCs in patients was significantly lower than that of healthy volunteers (0.11+/-0.09 vs. 0.19+/-0.06, P<0.05), while p53 mRNA expression was higher in patients than that of healthy volunteers (0.45+/-0.09 vs. 0.25+/-0.12, P<0.05).

PBMCs apoptosis in patients with MODS is increased abnormally. The expression of Bcl-2 mRNA in patients is decreased while p53 mRNA expression is increased. The results suggest that abnormal apoptosis of monocytes as well as abnormal expression of apoptosis associated genes occur in patients with MODS.