The gene expressions of matrix metalloproteinase-1 and its inhibitor in peripheral blood mononuclear cells from patients with chronic hepatitis B / 中华传染病杂志

ABSTRACT

Objective To examine the gene expression levels of matrix metalloproteinase-1(MMP-1), tissue inhibitor of metalloproteinase-1 ( TIMP-1) in peripheral blood mononuclear cells (PBMC) and sera in the patients with chronic hepatitis B (CHB) and to investigate the value of message RNA(mRNA) expression of MMP-1 and TIMP-1 for diagnosing liver fibrosis. Methods PBMC and sera samples were collected from 37 CHB patients and 20 healthy controls. The total RNA isolated from PBMC was reversely transcribed into cDNA. The mRNA levels of MMP-1 and TIMP-1 in PBMC were examined by real-time fluorescence quantitative reverse transcription polymerase chain reaction (FQ-RT-PCR). The serum levels of MMP-1 and TIMP-1 were determined by sandwich enzyme-linked immunosorbent assay (ELISA). Liver tissues were obtained from all these patients by biopsy and subsequently used for evaluating liver fibrosis stages (S). Intergroup comparison was performed by non parametric test. The correlation analysis was performed by Spearman. Results The MMP-1 and TIMP-1 mRNA levels in PBMC from healthy controls were low. The MMP-1 mRNA levels in PBMC from CHB patients were not significantly different from those in healthy controls,while the TIMP-1 mRNA levels were remarkably higher in CHB patients' PBMC compared to healthy controls. Both the MMP-1 mRNA levels in PBMC and the MMP-1 protein levels in sera were not significantly different among CHB patients at different disease stages and healthy controls (χ~2 =8. 960,P=0.111l ;χ~2 =7. 898, P = 0.211). However, the TIMP-1 mRNA levels in PBMC and the TIMP-1 protein levels in sera increased gradually along with the disease progressed from S1 to S4. The TIMP-1 mRNA levels in PBMC were (1.67±0. 84) lg copy/μL, (3. 48±2. 08) lg copy/μL,(5. 86±3. 47) lgcopy/μL and (8. 14 ± 6. 48) lg copy/μL from stage 1 to 4 respectively, while the protein levels of TIMP-1 in sera were (233. 73±64. 84) ,μg/L, (262. 10±71. 12) μg/L, (301. 15±62. 74)μg/L and(381. 15 ± 152. 75)μg/L, respectively. The differences between each stages were statistically significant (χ~2'= 14. 290, P=0.002,χ~2 = 12.209, P=0. 007). The TIMP-1 mRNA levels in PBMC and the TIMP-1 serum levels were positively correlated with liver fibrosis stage (r=0. 752, P<0. 01;r=0. 530, P=0. 008). Conclusions The TIMP-1 mRNA level in PBMC and TIMP-1 protein level in serum are closely related with liver fibrosis stages. These two parameters, especially the TIMP-1 mRNA level in PBMC, can be potentially new markers for diagnosing liver fibrosis.