Background: Acute rejection in liver transplants is one of the commonest causes of liver dysfunction in the early postoperative period. However, the factors involved in liver graft rejection are still unknown. Our study was aimed at ascertaining whether the degree of HLA class I and class II compatibility or pretransplant viral infection have any influence on early acute liver graft rejection.
Methods: We reviewed clinical and laboratory data in 190 consecutive patients who underwent a liver transplant. HLA-A, HLA-B, and HLA-DR typing for the establishment of an HLA match score was performed by a standard microcytotoxicity method. The existence of pretransplant viral infection was investigated in sera and biopsy tissue by serologic (hepatitis B virus, hepatitis C virus) and polymerase chain reaction (cytomegalovirus) techniques, respectively. The influence of these two factors in acute rejection and the interaction between them was also analyzed.
Results: A strong association between viral infection and acute rejection in the group with partial class I matching was found (odds ratio=7.75; P<0.0009), whereas no correlation was observed in the group with zero class I matching (odds ratio=0.98; P=0.81). The rejection percentage in the group in which partial class I match and viral infections coexisted was 60%, whereas in the partially class I-matched group without pretransplant viral presence it was 16%.
Conclusions: These findings suggest a participation of partial HLA class I compatibility in triggering acute rejection in recipients suffering preoperative viral infections and support the idea that HLA class I antigen matching could play a role as a linking element between the MHC-restricted T cell-mediated response to viral infection and the allogenic response in liver transplantation.