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During malaria infection, elevated levels of pro-inflammatory mediators and nitric oxide production have been associated with pathogenesis and disease severity. Previous in vitro and in vivo studies have proposed that both Plasmodium falciparum hemozoin and glycosylphosphatidylinositols are able to modulate blood mononuclear cells, contributing to stimulation of signal transduction and downstream regulation of the NF-κB signaling pathway, and subsequently leading to the production of pro-inflammatory cytokines, chemokines, and nitric oxide. The present review summarizes the published in vitro and in vivo studies that have investigated the mechanism of intracellular signal transduction and activation of the NF-κB signaling pathway in blood mononuclear cells after being inducted by Plasmodium falciparum malaria components. Particular attention is paid to hemozoin and glycosylphosphatidylinositols which reflect the important mechanism of signaling pathways involved in immune response.
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Objective To prepare the mB7-1-GPI-anchored Lewis vaccine and investigate its antitumor effects. Methods mB7-1-GPI was incorporated on Lewis tumor cells and mB7-1-GPI-anchoring tumor vaccine was prepared. The anti-tumor immunity induced by the prepared mB7-1-GPI-anchored Lewis tumor cell vaccine in tumor-bearing mice was observed. Results Flow cytometric analysis showed that mB7-1-GPI were positively expressed on the surface of Lewis tumor cells. After Lewis tumor cells incubated with mB7-1-GPI, the positive rate (PR) of mB7-1 antigen was 95.8% (0h), 93.6% (4h), 91.1% (8h) and the fluorescence intensity (FI) was 11.2(0h), 10. 6(4h), 9. 8(8h). The IL-2 and IFN-γ production of splenic lymphocytes + lewis cells was (25.9 ± 1.4) pg/ml, (56. 0± 3. 5 ) pg/ml. The IL-2 and IFN-γ production of splenic lymphocytes + lewis/mB7-1-GPI was ( 871.3 ± 10. 4 ) pg/ml, ( 1329. 0 ± 11.9 ) pg/ml. In 25 days, the mean diameter of tumor of Lewis/mB7-1 -GPI was shorter than Lewis( 1.4 ± 0. 21 )cm & ( 2. 5 ± 0. 27 )cm , P ＜ 0. 05 ). Lewis tumor cell-bearing C57BL/6 mice treated with Lewis/mB7-1-GPI vaccine survived much longer than mice treated with Lewis vaccine ( 75.2 ± 2. 0 ) d & (40. 2 ± 2. 0 ) d ( P ＜ 0. 05 ). Conclusion The Lewis tumor vaccine prepared with mB7-1-GPI fusion protein significantly inhibited the tumor growth in Lewis bearing mice. It represented an useful new strategy for attaching immunological factor onto tumor cell surfaces without genetic manipulation.
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Objective To study the expression of glycosylphosphatidylinositol(GPI) anchored protein in lymphocyte subsets of healthy individuals. Methods Flow cytometry and two/three color McAbs were used to detect CD59 expression in granulocytes, lymphocytes and subsets. Results In 50 samples, granulocytes mainly showed a single population of cells strongly positive for CD59, the percentage of CD59 expression was (98.6?1 5)%. Lymphocytes had a small population of weakly positive and negative for CD59, positive cells being (90 0? 14.9)%. CD3 +T cells had a similar profile as that of total lymphocytes, but there were more weakly positive /negative cells and less strong positive cells. As compared with CD3 +T cells, CD4 +T cells had a larger population of strongly positive for CD59, positive cells being (92.9?8.1)%; while CD8 +T cells had a smaller population of strongly positive, positive cells being (74.6?9.1)%. CD59 expression of activated T cells was between that of CD3 +and CD8 +T cells. CD45RA +and CD45RO +T cells both had a similar profile like that of CD3 +T cells. CD20 +B cells showed a similar profile to that of granulocytes, positive cells being (96.3?0 6)%. Conclusions Population of low or negative expression of CD59 among the lymphocytes of healthy controls was related to T cells, especially CD8 +T cells. B cells had uniform positive expression of CD59, and could be a candidate for detecting PNH.
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AIM: To construct human GPI-B7-1 fusion protein and investigate the therapeutic potentials in the treatment of tumors. METHODS: The chimeric GPI anchored-B7-1 gene was obtained by overlap PCR and inserted into expressing vector pcDNA3.1, named pc3.1/GPI-B7-1. pc3.1/GPI-B7-1was transfected into CHO cells by lipofectamine ~2 000 reagent. The CHO cells, expressing GPI-B7-1 on membranes, were obtained after selecting by G418. That was confirmed by flow cytometry, SDS-PAGE and Western blot. RESULTS: Recombinant vector pc3.1/GPI-B7-1 was successfully constructed and sequence result indicated that it was identical with reference sequence. The protein on transfected CHO cell membrane selected by G418 was confirmed to be GPI-anchored protein by flow cytometry, and GPI-B7-1 approximately 60 kD was conformed by SDS-PAGE and Western blot. CONCLUSION: A large amount of GPI-B7-1 fusion protein was obtained and will be further studied in the treatment of tumors.2? [