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A polyoxometalate-templated silver thiolate nanocluster, [Ag62(S(t)Bu)40(Mo20O66)(Mo6O19)3(CH3CN)2]·(CF3SO3)4 (1), has been isolated, in which a giant peanut-like silver(i)-thiolate cluster [Ag62(S(t)Bu)40](22+) encapsulates an unprecedented [Mo20O66](12-) polyoxoanion core. It opens a new approach for the synthesis of both elusive polyoxometalates and high-nuclearity silver(i)-thiolate nanoclusters.

Objective: To study the immunoregulatory effect of hepatitis B virus (HBV) e antigen (HBeAg) on peripheral blood monocytes (PBMCs)., Methods: PBMCs were isolated from patients with chronic hepatitis B (CHB; both HBeAg- and HBeAg+) and healthy controls, and cultured with recombinant HBeAg. The HBeAg-induced changes in expression of PD-1/PD-L1 were measured by flow cytometry of the cells and in secreted cytokines were measured by enzyme-linked immunosorbent assay of the supernatants. Comparisons between two groups were made by the independent-samples t-test; the relationship between PD-1/B7-H1 level and HBV DNA copy number was evaluated by Spearman's correlation analysis., Results: Exposure to HBeAg led to a significant decrease in CD3+CD4+ T lymphocyte-specific expression of IFNa for both the CHB patients' and healthy controls' samples (t = 2.382 and -4.190 respectively, P less than 0.01). For the HBeAg- CHB patients' and healthy controls' samples, the HBeAg exposure led to increased levels of secreted cytokines IL-6, IL-10 and TNFa (t = 2.504, 3.583 and 4.324, P less than 0.01 and t = 3.542, 6.246 and 5.273, P less than 0.01 respectively) and of CD14+ PBMC-specific expression of PD-L1 (t = 4.815 and 3.454, P less than 0.05 respectively). Compared to the HBeAg-negative CHB patients' and healthy controls' samples, the HBeAg+ CHB patients' samples had significantly lower CD3+CD4+ T cell-specific expression of IFNa (t = -3.177 and -4.541, P less than 0.01 respectively), but significantly higher levels of secreted IL-4 (t = 3.382 and 4.393, P less than 0.01 respectively), of CD3+ T cells-specific expression of PD-1/PD-L1 (t = 4.755, 2.942 and 4.518, 4.595, P less than 0.01 respectively), and of CD14+ T cells-specific expression of PD-L1 (t = 5.092 and 5.473, P less than 0.01 respectively). The CD3+ T cells-specific expression of PD-L1 was significantly higher in the samples from HBeAg- CHB patients than from the healthy controls (t = 3.214, P less than 0.01)., Conclusion: HBeAg was able to down-regulate the production of Th1-type cytokines (IFNgamma), and up-regulate the secretion of Th2-type cytokines (IL-6, IL-10) and the expression of PD-1/PD-L1on monocytes. These changes are conducive to the formation of immune tolerance to HBV. Therefore, HBeAg may play an important role in immune tolerance to chronic HBV infection.

The transmembrane protein (TM) encoded by gp37 gene plays a critical role when virus fusion with cell membrane occurs. Several highly conserved regions in TM are important targets for antivirus studies. Studies on structure and function of TM will provide basic information for anti-retrovirus, especially for avian leukosis virus. In the study, gp37 gene was amplified by PCR from the Chinese strain ALV-J-WS0701. The gp37 gene was cloned into pMD18-T vector, and was sequenced. Then, pFast-BacHTb-gp37 vector was constructed and expressed by baculovirus expression vector system. The expression product of gp37 gene was analyzed by indirect immunofluorescence assay and Western blot. The results showed that positive green fluorescence was present in sf9 cells infected with recombinant virus and a protein band with a molecular weight of 21kD was present in Western blot. It is concluded that gp37 gene was expressed in sf9 cells infected with recombinant virus successfully.