[Expression purification and clinical application of high-risk HPV16 E4 gene].

OBJECTIVE: To determine the relationship between serum antibody against HPV16 E4 and cervical cancer, and to construct HPV 16 E4 protein expression vector as an antigen to detect its corresponding serum antibody among different populations. METHODS: HPV16 E4 early gene was ligated into pRSET-A expression vector. The constructed plasmids were transformed into BL21 (DE3)cells, and induced to express HPV 16 E4 protein by isopropylthio-beta-D-galactoside (IPTG). The expressed E4 inclusions were denatured, purified through Ni-column, and renatured. After the activity was revealed, antibodies against HPV 16 E4 in the sera from healthy women and patients with chronic cervicitis and cervical cancer were respectively determined by enzyme-linked immunosorbent assay (ELISA) using the fusion protein as the antigen. RESULTS: HPV 16 E4 fusion protein of Mr 15*10(3) was expressed by pRSET-16E4 after IPTG induction. The fusion protein accounted for 30% of the total bacterial proteins and expressed as inclusive body. After purification with Ni-NTA agarose resin, the recombinant protein revealed purity of 95%, and activity of the renatured protein was identified by ELISA. The serum antibody-positive rate of HPV 16 E4 was 10.00%, 39.13% and 28.13%, respectively in 80 healthy women, 46 chronic cervicitis patients, and 32 cervical cancer patients. The antibody-positive rate in cervical cancer patients and chronic cervicitis patients were significantly higher than that in healthy women (P<0.01), while the difference between the antibody-positive rate in cervical cancer patients and chronic cervicitis patients was not significant. CONCLUSION: HPV 16 E4 protein expressed from pRSET-A/BL21 can be used in serological studies on cervical cancer-related HPV infection. Serum antibody against HPV16 E4 is present in a significantly higher percentage in cervical cancer and chronic cervicitis patients than in healthy women.

[Effect of berberine on left ventricular remodeling in renovascular hypertensive rats].

The purpose of this study is to evaluate the effects and the underline mechanisms of berberine on the cardiac function and left ventricular remodeling in rats with renovascular hypertension. The renovascular hypertensive model was established by the two-kidney, two-clip (2K2C) method in Sprague-Dawley (SD) rats. Two weeks after surgery, all the operated SD rats were randomly assigned into four groups: (1) renovascular hypertensive model group; (2) berberine 5 mg x kg(-1) group; (3) berberine 10 mg x kg(-1) group; (4) captopril 45 mg x kg(-1) group; and the sham operated rats were used as control. Four weeks after the drugs were administered, the cardiac function was assessed. The ratios of heart weight to body weight (HW/BW), left ventricular weight to body weight (LVW/BW) and right ventricular weight to body weight (RVW/BW) were compared between groups. Coronal sections of the left ventricular tissue (LV) were prepared for paraffin sections, picrosirius red and HE staining was performed. The left ventricular wall thickness (LVWT), interventricular septal thickness (IVST), the parameters of myocardial fibrosis indicated by interstitial collagen volume fraction (ICVF) and perivascular collagen area (PVCA) were assessed. Nitric oxide (NO), adenosine cyclophosphate (cAMP) and guanosine cyclophosphate (cGMP) concentrations of left ventricular tissue were measured. Berberine 5 mg x kg(-1) and 10 mg x kg(-1) increased the left ventricular +/- dp/dt(max) and HR. Berberine 10 mg x kg(-1) decreased HW/BW and LVW/BW. The image analysis showed that both 5 and 10 mg x kg(-1) of berberine decreased LVWT, ICVF and PVCA, while increased the NO and cAMP contents in left ventricular tissue. Berberine could improve cardiac contractility of 2K2C model rats, and inhibit left ventricular remodeling especially myocardial fibrosis in renovascular hypertension rats. And such effects may partially associate with the increased NO and cAMP content in left ventricular tissue.