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One new coordination polymer based on 4-[(8-hydroxy-5-quinolinyl)azo]-benzoic acid(H2L), {[CdL(H2O)]·H2O}n (1) was solvothermally synthesized and structurally characterized by single-crystal X-ray diffraction, infrared spectrometry, elemental analysis, powder X-ray diffraction(PXRD) and thermogravimetric analysis (TGA). In compound 1, L2− ligands link Cd(II) to form a sinusoidal ruffling layer, in which the carboxylic groups connect Cd(II) into an infinite Cd—O chain. And the layers are further stabilized by hydrogen bonding and π…π interactions, forming a three-dimensional(3D) supramolecular network. In addition, the fluorescent property of compound 1 was also investigated.

The virus-like particle(VLPs) vaccine is an ideal HIV-1 vaccine, which can simultaneously induce a neutralizing antibody reaction and cell-mediated immunity effectively. In this study, two kinds of plasmids have been used, one can express the HIV-1 main structure proteins, Gagpol and Env, and the other contains an antibiotic gene. The two kinds of plasmids have been cotransfected into 293 cells. A stable cell line that can express Gagpol and Env proteins efficiently and lastingly has been screened. It has been confirmed that Gagpol and Env proteins in the cell culture supernatant can be self-assembled into virus-like particles. The authors have detected the secretion of VLPs in the cell medium, defined the peak of the secretion, and followed and monitored the stability of expression.

Two eukaryotic vectors expressing 9 tandem repeats of human MUC1(VNTR), VR1012-VNTR, and pEGFP-VNTR, were constructed by cloning VNTR gene into VR1012 and pEGFP, respectively. VNTR stably expressing murine Lewis lung carcinoma(LLC) cell line(VNTR + LLC) was established by Lipofectamine-mediated transfection of pEGFP-VNTR into LLC cells. The EGFP expression was observed under a fluorescent microscope and VNTR expression in VNTR + LLC cells was confirmed by means of Western blotting. A syngenic graft tumor model was generated by subcutaneous injection of VNTR + LLC cells into C57/BL6 mice and tumor size increased rapidly with time and in a cell number dependent manner. VNTR mRNA expression in the tumor formed was confirmed by RT-PCR. After the third immunization mice were challenged subcutaneously with 5×10 5 VNTR + LLC cells, a significant reduction of subcutaneous tumor growth was observed in the groups immunized with VNTR plasmid DNA compared with that in the groups immunized with the vector DNA alone. Thus, the suppression of subcutaneous tumor was antigen-specific. This model is useful for the development of tumor vaccines targeting MUCI VNTRs.

To obtain a sufficient amount of glycoprotein for further studying the structure and function of HIV-1 envelope glycoprotein, amplified and modified HIV-1 envelope glycoprotein gene which recombined subtypes(850 amino acids) from Guangxi in China was inserted into Pichia pastoris expression vector pPICZαB; then the recombinant plasmid was transported into the yeast cells to induce the expression of Env protein with methanol. The results of SDS-PAGE and Western blot indicate that the envelope glycoprotein could be expressed in Pichia pastoris with productions of a 120000 glycoprotein and a 41000 glycoprotein, which showed satisfactory immunogenicity by indirect ELISA.

Virion infectivity factor(Vif) is one of the six accessory proteins of HIV-1 and is necessary for viral infectivity. Human Apolipoprotein B editing complex protein 3G(h-APOBEC3G) is a cytidine deaminase only expressed in “nonpermissive” cells and exhibits virus suppressive activity. With the aid of a Cullin-5 E3 ligase, Vif induces h-APOBEC3G degradation and with the destruction of this ligase, Vif is functionally inactive. Therefore, it is expected that blocking this E3 pathway would be a new therapeutic strategy against HIV-1 infection. In this article, the authors' took sequence alignment of the N-termini of Cullin-5 and three other members of the Cullin protein family, respectively. A set of small peptides has been synthesized based on the sequence comparison results and possible Vif-Cullin-5 interaction domains. Moreover, it has been demonstrated that several peptides can reduce virus infectivity in “nonpermissive” cells with a dose-responsive manner, but not in “permissive” cells. The results also indicate that the loss of viral infectivity may be because of the increase of APOBEC3G amount in the peptide-treated cells. It is concluded that peptides derived from Cullin-5 can block the APOBEC3G degradation induced by Vif and suppress HIV-1 infectivity. Therefore this study starts a novel strategy for the development of a new HIV-1 inhibitor.

Two new supramolecular polymers [M(2-NH2py)2 (ox)] [M = Co (1), Ni (2); 2-NH2py = 2-aminopyridine; ox = oxalate] were hydrothermally synthesized and characterized by elemental analyses, IR and single-crystal X-ray diffraction analyses. The isomorphic compounds 1 and 2 both possess one-dimensional zigzag chain structures, which are composed of [M(2-NH2py)2]2+ units bridged by tetradentate oxalate ligands to form three-dimensional supramo-lecular network via the C—H…O hydrogen bonds and π-π stacking interactions. Compound 1 displays antiferromagnetic interaction.