Impact of 5-Fu/oxaliplatin on mouse dendritic cells and synergetic effect with a colon cancer vaccine

Objective： The aim of the present study was to investigate the effects of 5-fluorouracil（5-Fu） and oxaliplatin on the function and activation pathways of mouse dendritic cells（DCs）, and to clarify whether 5-Fu/oxaliplatin combined with the CD1d-MC38/α-galactosylceramide（α-GC） tumor vaccine exhibits synergistic effects on the treatment of colon cancer in mice.Methods： The combination of the Toll like receptor（TLR） ligands and/or 5-Fu/oxaliplatin was added into myeloid-derived DCs in vitro culture. DC phenotypic changes were detected by flow cytometry, and the secretion of DC cytokines was detected by cytometric bead array（CBA）. A MC38 mouse colon cancer model was constructed and the DCs were isolated from the spleen, tumor tissue and lymph nodes following intraperitoneal injection of 5-Fu/oxaliplatin. The cell phenotypes were detected by flow cytometry. The tumor infiltrating leukocytes,splenocytes and lymph node cells were co-cultured with the dead MC38 tumor cells, and the secretion levels of interferon-γ（IFN-γ） were detected. 5-Fu/oxaliplatin combined with our previously developed CD1d-MC38/α-GC tumor vaccine was used to inhibit the growth of MC38 colon cancer in mice, and the tumor growth rate and survival time were recorded.Results： 5-Fu/oxaliplatin exerted no significant effect on the expression of the stimulating phenotypes of DCs in vitro, while it could reduce the expression of programmed death ligand 1/2（PD-L1/L2） and promote interleukin-12（IL-12） secretion by DCs. Furthermore 5-Fu/oxaliplatin was beneficial to the differentiation of T-helper 1（Th1） cells. 5-Fu/oxaliplatin further enhanced the stimulating phenotypic expression of DCs in tumor bearing mice, decreased PD-L1/L2 expression, and specifically activated the lymphocytes. The CD1d-MC38/α-GC tumor vaccine combined with 5-Fu/oxaliplatin could exert a synergistic role that resulted in a significant delay of the tumor growth rate, and an increase in the survival time of tumor bearing mice.Conclusions： 5-Fu/oxaliplatin decreased the expression of the DC inhibitory phenotypes PD-L1/L2, promoted DC phenotypic maturation in tumor bearing mice, activated the lymphocytes of tumor bearing mice, and exerted synergistic effects with the CD1d-MC38/α-GC colon cancer tumor vaccine.

Early activated hepatic stellate cell-derived molecules reverse acute hepatic injury

AIM: To test whether hepatic stellate cells(HSCs) at different activation stages play different roles in acetaminophen(APAP)-induced acute liver injury(ALI).METHODS: HSCs were isolated from mouse liver and cultured in vitro.Morphological changes of initiation HSCs [HSCs(5d)] and perpetuation HSCs [HSCs(p3)] were observed by immunofluorescence and transmission electron microscopy.The protective effects of HSCderived molecules, cell lysates and HSC-conditioned medium(HSC-CM) were tested in vivo by survival and histopathological analyses.Liver injury was determined by measuring aminotransferase levels in the serum and by histologic examination of tissue sections under a light microscope.Additionally, to determine the molecular mediators of the observed protective effects of initiation HSCs, we examined HSC-CM using a highdensity protein array.RESULTS: HSCs(5d) and HSCs(p3) had different morphological and phenotypic traits.HSCs(5d) presented a star-shaped appearance with expressing α-SMA at non-uniform levels between cells.However, HSCs(p3) evolved into myofibroblast-like cells without lipid droplets and expressed a uniform and higher level of α-SMA.HSC-CM(5d), but not HSC-CM(p3), provided a significant survival benefit and showed a dramatic reduction of hepatocellular necrosis and panlobular leukocyte infiltrates in mice exposed to APAP.However, this protective effect was abrogated at higher cell masses, indicating a therapeutic window of effectiveness.Furthermore, the protein array screenrevealed that HSC-CM(5d) was composed of many chemokines and growth factors that correlated with inflammatory inhibition and therapeutic activity.When compared with HSC-CM(p3), higher levels of monocyte chemoattractant protein-1, macrophage inflammatory protein-1γ, hepatocyte growth factor, interleukin-10, and matrix metalloproteinase-2, but lower levels of stem cell factor and Fas-Ligand were observed in HSCCM(5d).CONCLUSION: These data indicated that initiation HSCs and perpetuation HSCs were different in morphology and protein expression, and provided the first experimental evidence of the potential medical value of initiation HSC-derived molecules in the treatment of ALI.

Research Progress of Cold Resistance Mechanism of Cassava

Cassava is vulnerable to frost and snow, so it is suitable for planting in tropical and subtropical region. Low temperature is an important environment factor affecting the growth and development and production of cassava, and the region with annual average temperature below 15 ℃ is not conducive to its normal growth and development. The improvement of cold resistance of cassava can increase the planting area and improve the yield and quality of cassava. In this study, morphological,physiological and biochemical and molecular researches on cold resistance of cassava, as well as the latest research progress,were reviewed in this paper. At the same time, some potential difficulties in the research on cold resistance of cassava were put forward, and the future work focus was also discussed.