Transforming growth factor β as a possible independent factor in chronic hepatitis B

To investigate the association between immune-cell-related cytokines and the development of chronic hepatitis B (CHB), patients with chronic hepatitis B virus (HBV) infection in the immunotolerant (IT) phase (n = 30) or hepatitis B envelope antigen (HBeAg)-positive CHB (n = 250) were enrolled in this study. Serological indicators and plasma cytokine levels were measured at the time of enrollment. The results showed that there were significant differences in the median age of the patients (27 vs. 31 years), alanine aminotransferase levels (ALT, 29.85 vs. 234.70 U/L), alanine aminotransferase levels (AST, 23.40 vs. 114.90 U/L), HBsAg levels (4.79 vs. 3.88 log₁₀ IU/ml), HBeAg levels (1606.36 vs. 862.47 S/CO), and the HBV DNA load (8.17 vs. 6.71 log₁₀ IU/ml) between the IT and CHB groups (all P < 0.01). The median values of Fms-like tyrosine kinase 3 ligand (FLT3-L), interferon-gamma (IFN-γ), interleukin- 17A (IL-17A), and transforming growth factor beta (TGF-β1) were significantly higher in the IT group than in the CHB group (FLT3-L, 41.62 vs. 27.47 pg/ml; IFN-γ, 42.48 vs. 33.18 pg/ml; IL-17A, 15.66 vs. 8.90 pg/ml; TGF-β1, 4921.50 vs. 2234 pg/ml; all P < 0.01). The median IFN-α2, TGF-β3 and IL-10 levels in the IT group were significantly lower than those in the CHB group (IFN-α2, 15.24 vs. 35.78 pg/ml, P = 0.000; TGF-β3, 131.69 vs. 162.61 pg/ml, P = 0.025; IL-10, 5.02 vs. 7.9 pg/ml, P = 0.012). Multivariate logistic regression analysis indicated that TGF-β 1 (OR = 0.999, 95% CI 0.999-1.000, P < 0.001) and TGF-β2 levels (OR = 1.008, 95%CI 1.004-1.012, P < 0.001) were modestly but significantly associated with the incidence of CHB. The results suggest that TGF-β level might be an independent factor related to the occurrence of CHB.