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 establish tissue biobank of osteoarthritis in Beijing Jishuitan Hospital to promote orthopedic research study in China.Methods Fresh tissue or blood samples were collected from patients who underwent surgical operation for osteoarthritis since July 2007.Clinical information of the patientswasalsocollected.MicrosoftAccessdatabasesystemwasusedforthemanagementof information.Results From July 2007 to November 2011,a total of 2605 medical records and15188 tissue or blood samples were collected.Among them,165 tissue samples and 2005 blood samples were provided for molecular biology or epidemiological research.Conclusion Human tissue biobank is important for research work.Present osteoarthritis tissue collection and storage is feasible and could supply quality samples for study.

Objective:To analyze the genetic variant and molecular pathogenesis in a Chinese pedigree affected with Multiple epiphyseal dysplasia (MED).Methods:A MED pedigree which had presented at the Beijing Jishuitan Hospital Affiliated to Capital Medical University on September 13, 2020 was selected as the study subject. Clinical data of the pedigree were collected. Peripheral blood samples were drawn from pedigree members for the extraction of genomic DNA. Whole exome sequencing (WES) was carried out for the pedigree. Candidate variant was verified by Sanger sequencing. Wild type and mutant SLC26A2 expression plasmids were constructed and transfected into human primary chondrocytes. The effect of the variants on the protein localization and cell proliferation was determined by immunofluorescence and CCK8 assays. Results:WES and Sanger sequencing revealed that the proband has harbored compound heterozygous variants of the SLC26A2 gene, including a paternally derived c. 484G>T (p.Val162Leu) missense variant and a maternally derived c. 485_486delTG (p.Val162Glyfs*12) frameshifting variant. The SLC26A2 WT and its mutant SLC26A2 Val162Leu and SLC26A2 Val162Glyfs*12 expression plasmids were distributed in the nuclei and cytoplasm of human primary chondrocytes. Compared with SLC26A2 WT, the expressions of SLC26A2 Val162Leu and SLC26A2 Val162Glyfs*12 were decreased, along with reduced proliferation of human primary chondrocytes. Conclusion:The c. 484G>T and c. 485_486delTG compound heterozygous variants of the SLC26A2 gene may affect the proliferation of human primary chondrocytes and underlay the pathogenesis of MED in this pedigree.