RESUMO
AIM: To study the association between host immunity and hepatitis B virus (HBV) recurrence after liver transplantation. METHODS: Peripheral blood mononuclear cells (PBMC) were isolated from 40 patients with hepatitis B and underwent orthotopic liver transplantation (OLT) before and 2, 4, 8 wk after surgery. After being cultured in vitro for 72 h, the levels of INF-gamma and TNF-alpha in culture supernatants were detected with ELISA. At the same time, the quantities of HBV DNA in serum and PBMCs were measured by real time PCR. RESULTS: The levels of INF-gamma and TNF-alpha in PBMC culture supernatants decreased before and 2, 4 wk after surgery in turns (INF-gamma 155.52+/-72.32 ng/L vs 14.76+/-9.88 ng/L vs 13.22+/-10.35 ng/L, F = 6.946, P = 0.027 < 0.05; TNF-alpha 80.839+/-46.75 ng/L vs 18.59+/-17.29 ng/L vs 9.758+/-7.96 ng/L, F = 22.61, P = 0.0001 < 0.05). The levels of INF-gamma and TNF-alpha were higher in groups with phytohemagglutinin (PHA) than in those without PHA before surgery. However, the difference disappeared following OLT. Furthermore, INF-gamma and TNF-alpha could not be detected in most patients at wk 4 and none at wk 8 after OLT. The HBV detection rate and virus load in PBMC before and 2, 4 wk after surgery were fluctuated (HBV detected rate: 51.4%, 13.3%, 50% respectively; HBV DNA: 3.55+/-0.674 log10 copies/mL vs 3.00+/-0.329 log10 copies/mL vs 4.608+/-1.344 log10 copies/mL, F = 7.582, P = 0.002 < 0.05). HBV DNA in serum was 4.48+/-1.463 log10 copies/mL before surgery and <10(3) copies/mL after OLT except for one with 5.72 x 10(6) copies/mL 4 wk after OLT who was diagnosed as HBV recurrence. The levels of INF-gamma and TNF-alpha were lower in patients with a high HBV load than in those with a low HBV load (HBV DNA detected/undetected in PBMCs: IFN-gamma 138.08+/-72.44 ng/L vs 164.24+/-72.07 ng/L, t = 1.065, P = 0.297 > 0.05, TNF-alpha 80.75+/-47.30 ng/L vs 74.10+/-49.70 ng/L, t = 0.407, P = 0.686 > 0.05; HBV DNA positive/negative: IFN-gamma 136.77+/-70.04 ng/L vs 175.27+/-71.50 ng/L, t = 1.702, P = 0.097 > 0.05; TNF-alpha 75.37+/-43.02 ng/L vs 81.53+/-52.46 ng/L, t = 0.402, P = 0.690 > 0.05). CONCLUSION: The yielding of INF-gamma and TNF-alpha from PBMCs is inhibited significantly by immunosuppressive agents following OLT with HBV load increased, indicating that the impaired immunity of host is associated with HBV recurrence after OLT.