Showing papers by "Wannian Zhang published in 1998"

Granulocyte-macrophage colony-stimulating factor induces the differentiation of murine erythroleukaemia cells into dendritic cells.

Abstract: Dendritic cells (DC) are professional antigen-presenting cells (APC) within the immune system and antigen-pulsed DC can be used as an effective vaccine for active immunotherapy of cancer. Granulocyte-macrophage colony-stimulating factor (GM-CSF) plays an important role in the generation of DC. We previously showed that GM-CSF can induce murine erythroleukaemia cells (FBL-3) to differentiate into monocyte-like cells. To develop a new vaccinating method to stimulate the host immune response to leukaemia, we further investigate whether FBL-3 cells induced by GM-CSF can differentiate into DC in the present study. After being treated with GM-CSF, FBL-3 cells expressed high levels of 33D1 and NLDC-145, which are the specific markers of DC. The expression of MHC-II, B7-1, B7-2 and vascular cell adhesion molecule-1 (VCAM-1) was up-regulated markedly; the typical morphology of DC were also observed by electron microscopy. Functionally, the GM-CSF-induced FBL-3 cells could apparently stimulate the proliferation of naive allogeneic and autologous T lymphocytes and induce the generation of specific CTL more efficiently than the wild-type FBL-3 cells. Mice immunized with GM-CSF-induced FBL-3 cells could resist the subsequent challenge with the wild-type FBL-3 cells. Collectively, these data indicate that GM-CSF differentiates murine erythroleukaemia cells into DC phenotypically, morphologically and functionally. FBL-3-derived DC can be used as a new type of vaccine. Our results may have important implications for the immunotherapy of leukaemia.

Study on the rifampicin polylactic acid microspheres for lung targeting

Abstract: In this paper, the effects of different variables on the preparation of polylactic acid microspheres (PLA-MS) were studied. The optimized preparation conditions of rifampicin polylactic acid microspheres (RFP-PLA-MS) were aquired through orthogonal test. The paddle method was used to study the drug release properties of RFP-PLA-MS. Stability of RFP-PLA-MS at different temperatures was also studied. Pharmacokinetic and tissue distribution of RFP-PLA-MS after intravenous administration were carried out in rabbits. The experiments revealed that the RFP-PLA-MS was regular in its morphology with a mean diameter of 9.00 +/- 4.08 microns. The drug loading was 16.0% and encapsulation efficiency was 31.9%. The release properties could be expressed by the following equation: Q = 20.77 + 10.12 T 1/2 (gamma = 0.9892). The RFP-PLA-MS was stable after stored at 4 degrees C and room temperature under desiccated condition for three months. RFP-PLA-MS showed a combination of lung targeting and sustained drug release in experiments on rabbits.

[The construction and application of adenovirus vector coexpressing the heterodimer of human IL-12].

Abstract: OBJECTIVE To construct the recombinant adenovirus vector co-expressing the heterodimer of human interkeukin-12. METHODS The full-length cDNA encoding human IL-12 subunits p40 or p35 was cloned by RT-PCR separately. The cDNA was ligated with encephalomyocarditis internal ribosome entry site (IRES), placed under the control of CMV promoter, and inserted into E1-substituted adenovirus vector pAx1cw to produce the bicistronic coexpression vector. Subsequently, the hIL-12 recombinant adenovirus vector was cotransfected into 293 cells together with EcoT22I-digested Ad5 DNA-TPC, and the replication-deficient hIL-12 recombinant adenoviruses was generated efficiently by homologous recombination. RESULTS The human IL-12 recombinant adenoviruses were obtained with the titers of 2.1 x 10(9) pfu/ml. 48 hours after the infection of the 293 cells, HepG2 cells and human primary skin fibroblasts with hIL-12 recombinant adenoviruses, the hIL-12 expressions were detected by ELISA (30-50 ng/10(6) cells/24 h). The expressed hIL-12 could stimulate the in vitro proliferation and IFN-gamma production of human PMNC. CONCLUSION Prepared hIL-12 recombinant adenovirus vector can express biologically active hIL-12 and can be potentially used in cancer gene therapy.

Comparative molecular field analysis(CoMFA) of allylamine and benzylamine antimycotics

Abstract: "Active analog approach" has been employed to search the pharmacophoric conformation of the allylamine and benzylamine antimycotics A local minimum energy conformation, which is very similar to the crystallographically determined coordinate of naftifine or terbinafine, has been applied to build all compounds Comparative molecular field analysis (CoMFA) has been used to examine the correlations between the activities against 6 common human pathogenic fungi and the physicochemical properties of 62 allylamine and benzylamine compounds which had been aligned by rms fit rule The predictive abilities of the resulting 3D-QSAR models have been tested by 8 new synthetic compounds and 5 reported compounds Finally, we propose an interaction pattern between allylamine, benzylamine antimycotics and the active site of pseudoreceptor based on the results of 2D-QSAR and 3D-QSAR