[Hepatitis B virus antigen peptide presentation by Epstein-Barr virus-transformed peripheral blood B cells].

Objective: To establish an Epstein-Barr virus-transformed peripheral blood B cell line (BCL), and explore its phenotypic characteristics, the ability to secrete antibodies and cytokines, and the ability to present hepatitis B virus (HBV) antigen peptide. Methods: Peripheral blood mononuclear cells (PBMCs) were isolated from patients with HBV infection. Epstein-Barr virus supernatant was incubated to construct BCL. The expression of CD19, CD138, CD38, CD27 and the production levels of IFN - γ, IL-10, IL-6 were detected by flow cytometry. BCL loaded with HBV antigen peptide was incubated with in vitro-expanded autologous T cells. Intracellular staining was used to detect the level of interferon-gamma produced by T cells. Results: Compared with untransformed peripheral blood B cells, BCL had high expression levels of CD138, CD38 and CD27, and the difference was statistically significant (P < 0.05), while the level of IL-6 production was decreased, and the difference was statistically significant (P < 0.01). BCL loaded with HBV antigen peptide had significantly enhanced the production of interferon-gamma by in vitro-expanded autologous T cells, and the difference was statistically significant (P < 0.01). Conclusion: BCL highly expresses CD138, CD38 and CD27, but its ability to produce IL-6 decreases. BCL can improve the immune response efficiency of HBV-specific T cells to HBV antigen peptide, and serve as a new tool for hepatitis B immune research.

Isolation and characterization of levansucrase-encoding gene from Bacillus amyloliquefaciens.

The gene encoding levansucrase (LVS) from Bacillus amyloliquefaciens (sacB[BamP]) was isolated, sequenced and expressed in Bacillus subtilis. Analysis of the nucleotide sequence of sacB[BamP] reveals extensive homology with that of the B. subtilis LVS-encoding gene in the promoter and coding region. The sacB[BamP] gene cloned in a multicopy plasmid is induced by sucrose in B. subtilis.

Adsorption of Cd(II) ion and its complex compounds from solution on the surface of charcoal treated with an oxidation-negative ionizing method.

The adsorption characteristics of Cd(II) from electrolytic solution by activated charcoal have been investigated. It was found that the amount of adsorption of Cd(II) depends mainly on the pH value of the solution, the number of added inorganic ions, and oxygen-containing groups on the surface. The activated charcoal was treated with the oxidation-negative ionizing (OA) method to produce more oxygen-containing groups on the surface. The adsorption amount of Cd(II) on the treated activated charcoal increased remarkably. It was also found that the more powerful the acidity of the surface and the larger the adsorption amount of Cd(II), so the charged groups on the surface of activated charcoal are considered as the main adsorption-activated sites for inorganic ions. The adsorption characteristics of various complexes of Cd(II) on the surface of activated charcoal have also been investigated. Three types of adsorption configuration of the complexes of Cd(II) on the surface of activated charcoal were suggested according to the experimental results.