AIM:To explore the effect of Toll-like receptor ( TLR) 2 and TLR4 in Mycobacterium bovis Bacil-lus Calmette-Guérin (BCG)-induced human proximal renal tubule epithelial cell (HK-2) injury.METHODS:HK-2 cells were stimulated by BCG, and the expression of TLR2, TLR4, chemokine (C-X3-C motif) ligand 1 (CX3CL1) and trans-forming growth factor beta 1 ( TGF-β1 ) was detected by quantitative real-time PCR and Western blotting .TLR2 monoclonal antibody and TLR4 inhibitor were used to treat the HK-2 cells 1 h before BCG stimulation.The expression of CX3CL1 and TGF-β1 was evaluated by quantitative real-time PCR and Western blotting .RESULTS: BCG increased the expression of TLR2, TLR4, CX3CL1 and TGF-β1 in the HK-2 cells.Additionally, the expression of CX3CL1 and TGF-β1 was inhibited partly by TLR2 monoclonal antibody or TLR4 inhibitor.CONCLUSION:BCG is able to increase the production of TLR 2, TLR4, CX3CL1 and TGF-β1 in the HK-2 cells.TLR2 and TLR4 signaling pathways play important roles in tubule epitheli-al cell injury induced by BCG .

BACKGROUND: Whether human embryonic stem cells (hESCs) cultured on different feeder layers can maintain identical or similar characteristics remains unclear.OBJECTIVE: To compare the characteristics of hESCs cultured on human- and mouse- origin feeder layers.DESIGN, TIME AND SETTING: The in vitro cytology observation was performed at the Kunming Institute of Zoology, Chinese Academy of Sciences between September 2007 and February 2009.MATERIALS: Two ICR pregnant mice with 12.5-13.5 embryonic days were provided by Animal Center of Kunming Medical College. Immortalized human adult fibroblast (HAFi) cell line was presented by School of Medicine, Johns Hopkins University (USA). hESCs line was provided by Kunming Institute of Zoology, Chinese Academy of Sciences.METHODS: Mouse embryonic fibroblasts (MEF) were harvested from ICR mice by trypsinization method. HAFi were conventionally cultured. After γ ray treatment, two kinds of cells were incubated on 6-well gelatin-coated plate with density of 2.5×10~4/cm~3. hESCs were cultured on HAFi or MEF feeder cells containing β-mercaptoethanol DMEM/F12 and basic fibroblast growth factor.MAIN OUTCOME MEASURES: Morphology, expressions of specific molecular markers, Oct-4 positive rate, as well as cell doubling time of hESCs cultured by two methods were compared.RESULTS: ①BG02 cells on MEF and HAFi shared the similar morphology and characteristic pluripotency markers, which expressed SSEA-3, SSEA-4, TRA-1-60, TRA-1-81 and Oct-4, but not SSEA-1. However, the proportion of positive Oct-4 cells in hESCs colonies maintained on MEF was lower than that of HAFi (P < 0.05) with shorter doubling time (P < 0.05).CONCLUSION: hESCs cultured on MEF and HAFi represent some differences in the growth and pluripotency characteristics.

Objective To study the antitumor activity of Xerophilusin G on S180 cells,and Its mechanism.Methods Modified MTT assay was used to test the effect of Xerophilusin G on the proliferation of S180 tumor cell strain.The influences on tumor growth and immune organs of mice with transplanted sarcoma (S180) were observed.The cell cycle of S180 cell lines and mouse sarcoma (S180) was analyzed by flow cytometry.The lymphocyte proliferation activity of spleen stimulating was tested.The level of IL-2 in serum of mice with transplanted sarcoma (S180) was measured by ELISA.Results The IC50 of Xerophilusin G in S180 cell lines was 19.80 μg·mL-1,the LD50 in mouse for Xerophilusin G was 121.11 mg·kg-1 through intraperitoneal injection.The tumor inhibition rate of Xerophilusin G was 32.11％ and 41.60％,respectively at the doses of 3 and 6 mg · kg-1 (P ＜ 0.05).Compared with the control,the thymus,kidney and cardiac index were decreased.The cell proportion at G0/G1 phase of mouse sarcoma (S180) was increased.T and B cell proliferation activities in tumor-bearing mice were enhanced (P ＜ 0.05).As compared with control group,the serum level of IL-2 was decreased 90.9％ and 77.1％ in low-and medium-dose groups,respectively (P ＜ 0.05).Conclusion Xerophilusin G has remarkable effects in sarcoma (S180) bearing mice.The antitumor mechanism of Xerophilusin G might be related with G0/G1 phase arrest of mouse sarcoma (S180) cells and enhancing the activity of T and B cell but not related with increasing the secreting of IL-2.