Hepatitis B surface antigen (HBsAg) carrying preS sequences could be an ideal candidate for a new hepatitis B virus (HBV) vaccine with higher efficacy. Here we report the success in achieving efficient and stable expression of hepatitis B virus S antigen and preS1 epitope fusion protein (S/preS1) in CHO cells. The HMRCHEF53u/Neo-S/preS1 expression vector carrying S/preS1 gene was constructed and transfected into CHO-S cells. A stable and high-expression CHO cell line, named 10G6, was selected by ELISA and limiting dilution analysis. Western blotting analysis showed S/preS1 expressed from 10G6 cells possessed both S and preS1 antigenicity. 10G6 cells displayed characters of favorable growth and stable S/preS1 expression in repeated batch cultures as evaluated by viable cell density, viability and S/preS1 concentration. And cultivation of 10G6 cells in fed-batch mode resulted in S/preS1 production at 17-20 mg/L with viable cell density at 7 x 10(6)-10 x 10(6) cells/mL.
Animals ; CHO Cells ; Cricetulus ; Epitopes ; biosynthesis ; genetics ; Hepatitis B Surface Antigens ; biosynthesis ; genetics ; immunology ; Hepatitis B Vaccines ; biosynthesis ; genetics ; Hepatitis B virus ; Protein Precursors ; biosynthesis ; genetics ; immunology ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; Transfection

Objective To explore the risk factors for orchidism and the curative efficacy of intensive corticosteroids therapy for the testicular adrenal rest tumors ( TART ) in the patients with congenital adrenal hyperplasia due to 21-hydroxylase deficiency ( 21OHD) during childhood and pubescent periods. Methods A total 12 cases (27 case-times) with TART were adopted in intensive corticosteroids therapy, 7 cases (7case-times) as control group without intensive therapy. Retrospective analysis following parameters:( 1) The testicular volume and the echogenic characteristics of TART by B-mode ultrasound. ( 2 ) Serum levels of FSH, LH, testosterone, 17-hydroxyprogesterone, androstendion, and inhibin-B were measured. ( 3 ) Orchidism was defined by one of following events:serum level of inhibin-B≤3rd％ for norm, and/or serum level of testosterone<1. 47 ng/ml for the individual which is already in TannerⅣstage. ( 4) The relationship between regression of TART and intensive therapy project. Results The prevalence of TART in 21-OHD was 28.18％during 2-18 years old, and the youngest age with TART was 2. 48 year of old. The regression rate of TART by intensive therapy was higher than that of the control significantly, 20/30 and 1/11(tumor-times) respectively(P=0.004). When the dose of dexamethasone≥30％ of total doses of corticosteroids, the regression rate of TART was higher than those less than 30％ ones, or adopted hydrocortisone alone, were both respectively 16/20 and 4/10(P=0.045). The risk factors for orchidism related to early diagnosis:The TARTs stages in diagnosis (≥stages III;P=0.003) , the tumor in size, hyperechogenicity in B ultrasound of the tumors ( P = 0. 003 ) . Inhibin-B is the earliest displayed biochemical warker for orchidism. Conclusions The TART could regress when got early diagnosis and adopted intensive corticosteroids therapy on time. Delayed diagnosis was the main risk factor for orchidism. For early diagnosis of TART, we suggest to conduct the scrotal ultrasound regularly started from 2 years of age.