High serum apolipoprotein AIV levels in renal transplant recipients

Background: Human apolipoprotein (apo) AIV might play a role in post-transplant reverse cholesterol transport, which appears to be comparable to that seen in healthy subjects. However, there may be subtle differences between healthy individuals and renal transplant recipients, given the other abnormalities of lipoprotein metabolism in the latter. Therefore, the aim of the present study was to investigate possible changes of serum apo AIV levels in renal transplant recipients, and to evaluate potential factors influencing these levels. Patients and methods: Total and free serum apo AIV was determined in 36 clinically stable renal transplant recipients and in 20 sex- and age-matched healthy control subjects. Results: Mean total serum apo IV concentrations ( SD) were significantly higher in renal transplant recipients than in control subjects (202 +/- 102 vs 79 +/- 45 mg/l, p < 0.01). The percentage of lipoprotein-free fractions of apo AIV was comparable in both groups. The elevated total serum concentrations of apo AIV were mainly related to creatinine clearance and partially to serum triglyceride levels in renal transplant recipients. Conclusion: Our data suggest that the observed elevation of serum apo AIV concentrations in renal transplant recipients is essentially related to the presence of impaired renal function.