OBJECTIVETo investigate the relationship of Toll-like receptor 2 (TLR2) and viral hepatitis B through testing the expression of TLR2 in liver tissues of patients infected with HBV and in HepG2 and HepG2.2.15 cell lines.

METHODSExpression of TLR2 was determined by Elivision immunohistochemistry in liver tissues from patients with chronic viral hepatitis B (CHB), chronic severe hepatitis (CSH), from healthy controls and from cells of HepG2 and HepG2.2.15 hepatocellular carcinoma cell lines. Direct immunofluorescence flow cytometry was used to detect TLR2+ cell percentage and mean fluorescence intensity (MFI).

RESULTSThe intensity of TLR2 expression in liver tissues of CHB and CSH was significantly higher than that of the healthy controls (probability value less than 0.01). The positive staining was mainly located in the cytoplasm and on some cell membranes. In CHB, the intensity of TLR2 expression was positively correlated with the grade of necroinflammatory activity (r=0.597, P less than 0.01). There were significant differences of serum total bilirubin levels with different grades of positive staining of TLR2 (P less than 0.05). In liver tissues of the CHB patients, the positive staining of TLR2 was shown in small foci. MFI of TLR2 (10.7+/-2.8) and TLR2+ cell percentage (16.3%+/-7.0%) of HepG2.2.15 cells were both significantly higher than those of HepG2 cells (1.0+/-0.3, 0.4%+/-0.1%, P less than 0.01).

CONCLUSIONSExpression of TLR2 is closely correlated with hepatitis B, especially to the grades of its necroinflammatory activity.