Brain death affects the hepatic immunogenicity of pigs

Immunomodulatory response in an experimental model of brain death

Liver transplantation has come a long way and is now regarded as the gold standard treatment for end-stage liver failure. The great majority of livers utilized in transplantation come from brain-dead donors. A broad inflammatory response characterizes BD, resulting in multiorgan damage. This process is primarily mediated by cytokines, which increase the immunogenicity of the graft. In male Lewis rats, we evaluated the immune response in a BD liver donor and compared it to that of a control group. We studied two groups: Control and BD (rats subjected to BD by increasing intracranial pressure). After the induction of BD, there was an intense rise in blood pressure followed by a fall. There were no significant differences observed between the groups. Blood tissue and hepatic tissue analyzes showed an increase in plasma concentrations of liver enzymes (AST, ALT, LDH and ALP), in addition to pro-inflammatory cytokines and macrophages in liver tissue in animals submitted to BD. The current study found that BD is a multifaceted process that elicits both a systemic immune response and a local inflammatory response in liver tissue. Our findings strongly suggested that the immunogenicity of plasma and liver increased with time following BD.

Immunomodulatory effects of thalidomide in an experimental brain death liver donor model

Brain death is characterized by a generalized inflammatory response that results in multiorgan damage. This process is mainly mediated through cytokines, which amplify graft immunogenicity. We investigated the immunological response in a brain death liver donor model and analysed the effects of thalidomide, a drug with powerful immunomodulatory properties. Brain death was induced in male Lewis rats. We studied three groups: Control (sham-operated rats in which trepanation was performed without inserting the balloon catheter), BD (rats subjected to brain death by increasing intracranial pressure) and BD + Thalid (BD rats receiving thalidomide after brain death). After 6 h, serum levels of AST, ALT, LDH, and ALP as well as systemic and hepatic levels of TNF-α, IL1-β, IL-6, and IL-10 were analysed. We also determined the mRNA expression of MHC Class I and Class II, NF-κB, and macrophage infiltration. NF-κB was also examined by electrophoretic mobility shift assay. Thalidomide treatment significantly reduced serum levels of hepatic enzymes and TNF-α, IL-1-β, and IL-6. These cytokines were evaluated at either the mRNA expression or protein level in liver tissue. In addition, thalidomide administration resulted in a significant reduction in macrophages, MHC Class I and Class II, and NF-κB activation. This study reveals that thalidomide significantly inhibited the immunologic response and graft immunogenicity, possibly through suppression of NF-κB activation.

The influence of brain death on donor liver and the potential mechanisms of protective intervention

Brain-dead donors have become one of the main sources of organs for transplantation in Western countries. The quality of donor organs is closely related to the outcome of the transplantation. Experimental studies have confirmed the inferior graft survival of livers from brain-dead donors compared with those from living donors. Studies conducted in the past 10 years have shown that brain death is associated with effects on the decreased donor organ quality. However, whether the decrease in the viability of donor organs is caused by brain death or by the events before and after brain death remains uncertain. The purpose of this review is to introduce the advances and controversies regarding the influence of brain death on the viability of donor livers and to summarize the mechanisms of the different protective interventions for donor livers.

The influence of brain death on donor liver and the potential mechanisms of protective intervention

Brain-dead donors have become one of the main sources of organs for transplantation in Western countries. The quality of donor organs is closely related to the outcome of the transplantation. Experimental studies have confirmed the inferior graft survival of livers from brain-dead donors compared with those from living donors. Studies conducted in the past 10 years have shown that brain death is associated with effects on the decreased donor organ quality. However, whether the decrease in the viability of donor organs is caused by brain death or by the events before and after brain death remains uncertain. The purpose of this review is to introduce the advances and controversies regarding the influence of brain death on the viability of donor livers and to summarize the mechanisms of the different protective interventions for donor livers.