Study of apoptosis and heat shock protein (HSP) expression in hepatocytes following radiofrequency ablation (RFA).

BACKGROUND

Radiofrequency ablation (RFA) of the liver produces necrosis of the hepatocytes. Histological examination shows a sharp demarcation between ablated and normal liver tissue. This experiment was carried out to study the cellular injury produced by RFA in area surrounding the ablated tissue and effect of reperfusion on this zone.

MATERIAL AND METHODS

Five pigs underwent RFA of liver parenchyma. Four pigs were sacrificed 30 min after RFA and one pig was sacrificed 5 days later. Ablated lesions including surrounding liver parenchyma was examined for apoptosis and HSP 70 expression.

RESULTS

There was a zone of transition surrounding the necrotic ablated area that showed apoptosis as well as increased HSP 70 expression. This was more prevalent in the pig that was sacrificed 5 days later.

CONCLUSION

RFA produces sub lethal injury in the zone of transition causing apoptosis and increase in HSP 70 expression. Increased HSP expression enhances immunogenicity of these cells that can have therapeutic implications for the treatment of liver.