Study on role of TIGIT signal in Th1/Th2 balance in Schistosoma japonicum-infected mice / 中国血吸虫病防治杂志

Objective To investigate the role of TIGIT signal in Th1/Th2 balance in the process of Schistosoma japonicum in-fection.Methods Male C57BL/6 mice were infected with cercariae of S.japonicum,and normal uninfected mice served as the controls.The percentages of TIGIT+cells,Ki67+CD3+CD4+TIGIT+cells,Ki67+CD3+CD4+TIGIT-cells,IFN-γ+CD3+CD4+TIGIT+cells,IFN-γ+CD3+CD4+TIGIT- cells,IL-4+CD3+CD4+TIGIT+cells and IL-4+CD3+CD4+TIGIT- cells were evaluated in mouse spleen by flow cytometry.Results The proportion of TIGIT+CD4+T cells was higher in the spleen of S.japonicum-infected mice than in the normal uninfected mice(29.30%±0.70% vs.3.09%±0.50%;t=8.834,P<0.01).However,no significant differ-ence in the percentages of TIGIT+CD8+T cells between the infection group and normal controls(3.61% ± 0.26% vs. 3.58% ± 0.16%;t=0.108,P>0.05),and no significant difference was detected in the percentages of TIGIT+cells in non-T cells be-tween the infection group and controls(1.86%±0.19% vs.1.37%±0.17%;t=1.931,P>0.05).In addition,the proportion of Ki67 in the TIGIT+cells was higher than that in the TIGIT-cells(17.03%±0.64% vs.6.59%±0.37%;t=14.09,P<0.01).The Th2/Th1 ratio was higher in the TIGIT+CD4+T cells than in the TIGIT-CD4+T cells(39.28%±3.75% vs.11.79%±1.64%;t=6.721,P<0.01).Conclusion The TIGIT signaling may be involved in the development of Th2 responses in the mice infected with S.japonicum.

Effects of glycolytic pathway on generation of regulatory T cells during Schistosoma japonicum infection / 中国血吸虫病防治杂志

Objective To assess the influence of glycolytic pathway on the proportion and numbers of regulatory T cells dur-ing Schistosoma japonicum infection. Methods A S. japonicum-infected mouse model was established,and C57/BL6 male mice infected with S.japonicum were subjected to intraperitoneal injections of with the glycolytic inhibitor 2-Deoxy-D-glucose (2DG)or PBS for 6 times,and then the cells from spleen or mesenteric lymph nodes(LNs)were isolated and analyzed by flow cytometry(FCM)to detect the percentage of Glut1+CD4+T cells and Treg cells. Results The proportions of Glut1+CD4+T cells in the spleen(43.58%±2.50% vs.21.15%±0.96%;t=8.834,P<0.01)and mesenteric LNs(38.97%±1.97% vs.28.40%± 2.11%;t=3.662,P<0.05)were higher in the normal mice than those in the infected mice,and the percentages of Treg cells in the spleen(6.83% ± 0.21% vs. 13.30% ± 0.35%;t = 15.65,P < 0.01)and LNs(8.26% ± 0.15% vs. 14.37% ± 0.44%;t =13.14,P<0.01)were lower in the normal mice than those in the infected mice.In addition,the proportions of Treg cells in the spleen(15.50%±0.76% vs.13.07%±0.15%;t=3.130,P<0.05)and LNs(17.00% ± 0.41% vs.13.83% ± 0.18%;t=6.947, P<0.01)were higher in the infected mice injected intraperitoneally with 2DG than those in the infected mice injected intraperi-toneally with PBS. Conclusion Glycolytic pathway inhibits Treg differentiation in the spleen and mesenteric LNs of S.japoni-cum-infected mice.

Schistosoma japonicum heat shock protein 60 enhances regulatory T cell im-munosuppressive function by promoting the expressions of IL-10 and TGF-β / 中国血吸虫病防治杂志

Objective To explore the possible mechanisms by which Schistosoma japonicum heat shock protein 60(SjH-SP60)enhances CD4+CD25+regulatory T cell(Treg)immunosuppressive function.Methods An in vitro method was used to investigate the effect of SjHSP60 on Treg immunosuppressive activity.Co-cultures in transwells and in vitro suppression assay were performed to investigate how SjHSP60 enhanced the immunosuppressive function of Tregs.Intracellular cytokine staining combined with flow cytometry was used to detect Treg-expressing IL-10 and TGF-β,and flow cytometry was also used to analyze the expressions of Foxp3 and CTLA-4 in Tregs.Results SjHSP60 enhanced the immunosuppressive function of Tregs.Soluble cytokines IL-10 and TGF-β mediated inhibitory activity of SjHSP60-triggered Tregs.SjHSP60 induced significant increases in both IL-10 and TGF-β expressions of Tregs.Further investigation showed significant increased Foxp3 and CTLA-4 in SjHSP60-trggered Tregs.Conclusion SjHSP60 enhances Treg immunosuppressive function by promoting the expressions of IL-10 and TGF-β,possibly due to SjHSP60-mediated induction of Foxp3 and CTLA-4 in Tregs.

Analysis of complexity in Chinese meteria medica industrial chain / 中国中药杂志

Chinese meteria medica (CMM) chain is a long-span chain covering agriculture which mainly depends on the forces of nature as well as high-tech CMM industry, CMM expertise industry and fast developing CMM circulation industry. Imbalance among the development of these industries produces bottlenecks and hinders the operation of the entire production chain. After analyzing the structure of Chinese meteria medica industrial chain from the perspective of national economy industry, three industry classifications and differentiation of factor intensity, we conclude that the complex structure of CMM industry chain is attributable to these three aspects. And the complexity is mainly shown at complex industry, varied product types, different coordination of various industrial sections and different technical growth speed of varied industry. We propose that structural complexity is the natural property of the chain, which is the main reason of industry sector development imbalance and bottleneck. Results of this research could provide theoretical analysis for future research on the coordination of industrial chain and the efficiency of resource allocation.

Establishment of an assay for PrP(Sc) detection based on streptomycin precipitation / 病毒学报

To establish a new Western blotting assay for PrP(Sc) detection, we optimized the Western blotting assay with a precipitation procedure of streptomycin sulfate. After digestion with PK, 10% scrapie infected hamster brain homogenates were incubated with 60 mmol/L streptomycin and the precipitated PrP(Sc) was recovered by centrifugation. The enrichment of PrP(Sc) by streptomycin sulfate precipitation was evaluated using Western blotting assay. The results showed streptomycin could bind to PK-treated PrP(Sc), forming high molecular masses, but not influence the glycosylated patterns on SDS-PAGE. Western blot assay revealed that the detective sensitivity of the streptomycin-precipitation PrP(Sc) was remarkably improved. As a sensitive, specific, rapid and flexible protocol for PrP(Sc), the protocol in this study has the potential utility, alone or combined with other techniques, for the detection of low level PrP(Sc) in the specimens from central nerve system, or from peripheral organs or body fluids.

Interaction analysis between various PrP fusion proteins and the tubulin in vitro / 病毒学报

In order to further study the potential interaction between PrP protein and the tubulin and identify the binding region in PrP with tubulin, native tubulin was extracted from rabbit brian tissues, while various recombinant PrP proteins were expressed and purified. The possible molecular interaction between various PrP fusion proteins and tubulin was tested by pull-down and immunoprecipitation assays. Remarkable molecular interaction between the full length PrP and tubulin was observed by pull-down and immunoprecipitation assays. Subsequently, the binding regions within PrP with tubulin were firstly mapped in the aa 23 -- 91 region within N-terminus of PrP peptide. The studies of the association of PrP with tubulin may further provide insight into the unresolved mechanism of active transport of PrP protein in neurons and possible cellular pathways by which prion causes disease.

Treatment of scrapie pathogen 263K with tetracycline partially abolishes protease-resistant activity in vitro and reduces infectivity in vivo / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To study the possible effect of tetracycline on protease-resistant activity in vitro and infectivity in vivo of a scrapie strain 263K.</p><p><b>METHODS</b>Scrapie pathogens were incubated with tetracycline at different concentrations for various periods of time and protease-resistant PrP signals were evaluated with proteinase K-treatment and Western blots. The preparations treated with tetracycline were intracerebrally inoculated into golden hamsters and typical TSE manifestations were noted. PrPSc in brain tissues of the infected animals was detected by PrP specific Western blot assays.</p><p><b>RESULTS</b>Protease-resistant PrP was significantly reduced in or removed from the preparations treated with tetracycline in a dose-dependant manner. Compared with the control group after incubated for 53.75 +/- 0.50 days, the preparations treated with 5 mmol/L and 20 mmol/L tetracycline prolonged the incubation time of 61.5 +/- 1.73 and 59.5 +/- 0.58 days (P < 0.05).</p><p><b>CONCLUSION</b>Treatment of scrapie pathogen 263K with tetracycline reduces or removes its protease-resistant activity in vitro.</p>

Preliminary analyses for influence of mutant PrPs with different number of octapeptide / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>The present study was conducted to understand the effects of PrP in different octapeptide repeats on proliferation of HeLa cells.</p><p><b>METHODS AND RESULTS</b>Mutant PrPs with octapeptide repeat insertion were transiently expressed in HeLa cells and their results of MTT assay showed stronger cytotoxic effect on the proliferation of cells than wild-type PrP. Annexin V/PI assay also demonstrated that the expression of mutant PrPs was much easier to induce apoptosis than wild-type in HeLa cells. The percentage of both early and late stage apoptosis in mutant groups were significantly higher than that of wild type.</p><p><b>CONCLUSION</b>These data suggest that the expression of mutant PrPs associated with familial CJD is much easier to induce apoptosis in cultured cells than expression of wild type PrP.</p>

Interaction between various PrP segments and GFAP in vitro / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To study the potential interaction between PrP protein and glial fibrillary acidic protein (GFAP) and identify the binding region within PrP with GFAP.</p><p><b>METHODS</b>The supernatant of healthy and scrapie-infected hamsters' brain homogenate was prepared, while various recombinant PrP or GFAP proteins were expressed using prokaryotic-expressing or in-vitro translation system. The possible molecular interaction between PrP proteins and GFAP was tested by Pull-down and immunoprecipitation assays.</p><p><b>RESULTS</b>Both native PrP(C) and its protease-resistant isoform (PrP(Sc)) formed complexes with the native GFAP. The full-length recombinant PrP proteins interacted with GFAP. The domain responsible for interacting GFAP was located at C-terminal of PrP (residues 91 to 231).</p><p><b>CONCLUSION</b>The studies of the association of PrP with GFAP may further provide insight into a potential role of GFAP in the biological function of PrP and the pathogenesis of prion disease.</p>

Establishment of cell free conversion system with biotin-labelled recombinant PrPsen expressed in E. coli / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To report a protocol using biotin-labelled PrP protein in cell free conversion assay instead of isotope.</p><p><b>METHODS</b>A hamster PrP protein (HaPrP) was expressed in E. coli and purified with HIS-tag affinity chromatograph. After being labelled with biotin, HaPrP was mixed with PrPSc preparation from scrapie strain 263K.</p><p><b>RESULTS</b>Protease-resistant bands were detected after four-day incubation.</p><p><b>CONCLUSION</b>The new conversion model provides a reliable, easily handling, and environment-friendly method for studies of prion and transmissible spongiform encephalopathies.</p>

Molecular epidemiological study on rubella virus / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To understand the hereditary and variant characteristics of rubella virus(RV), especially the strains isolated from China, investigating the epidemical trend and variation principle of RV.</p><p><b>METHODS</b>The envelope glycoprotein E1 gene was amplified from rubella virus by RT-PCR. After sequencing, the gene sequence was handled by the software DNASTAR and the phylogenetic tree was drawn to analyze the molecular epidemiological characteristics of RV.</p><p><b>RESULTS</b>The sequence of RV strain JR23 was sequenced, the phylogenetic tree was drawn taking 30 strains isolated at different times and locations in GenBank, including three strains from China as reference. The regions that encode the peptides which react with the HI antibody and the neutralization antibody were compared to show if there was any amino acid mutation in the sequence. (1) In general, the nucleotide and amino acid sequences of RV were highly conserved. The four strains isolated from China had relatively large variations. Strain 379 and strain BRD constituted genotype II, which is different from the other 29 strains. Further study is needed to understand their heritable resources and biological characteristics. (2) Strain JR23 showed little difference from the strains that were epidemic during 1960s in UK, USA and Japan, so maybe it is the derivative strain of that in epidemic 1960s. But the accurate epidemic time is not known.</p><p><b>CONCLUSION</b>There are differences among areas and time in epidemics of rubella. The mobility and the region difference seem to be the key factors that affect the epidemic characteristics of RV.</p>

Inhibition effects of rhubarb ethanol extract on herpes simplex virus infection in vivo / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To know the anti-viral effects of rhubarb ethanol extract (REE) on herpes simplex virus(HSV) infection in vivo.</p><p><b>METHODS</b>BALB/c mice inoculated from tail vein with 0.15 ml of HSV (TCID50=10(3)) were injected hypodermically with REE next day. After divided into seven groups, three groups of mice were given different doses of REE respectively and the other groups as controls. Pathological sections from the liver, spleen, kidney were made at different times of postinfection, and their pathological changes were observed under microscope; the virus titers in viscera were assayed by using plaque formation technique and the rhubarb inhibitions to the infection of HSV in vivo?were observed.</p><p><b>RESULTS</b>No toxic response to mice were observed for REE injected hypodermically; no pathological changes were observed in different therapy groups of spleens. And those in livers and kidneys at medium- and high-dosed groups disappeared quickly. The effect of low-dosed group was equal to that of positive control group, acyclovir(ACV); the results of the titer tests showed that the virus decreased rapidly by using REE, especially in the medium- and high-dosed groups which were much more marked than the low-dosed group; Q test of the data showed that total mean value had statistical significance (F=49.1459, P<0.01); moreover there were statistical significance between therapy groups (ACV, DH1, DH2, DH3) and non-therapy groups (VC) (P<0.01 ) and between DH2, DH3 and DH1 (P<0.01); no statistical significance were found between DH1, DH2 or DH3 and ACV (P>0.05). Results show that as to the effect of decreasing the average of the total titer, rhubarb is as effective as ACV; furthermore, the medium- and high-dosed groups are superior to the low-dosed group.</p><p><b>CONCLUSIONS</b>REE has significant anti-viral effect on HSV in vivo; there will be a wide application foreground of it in clinical usage.</p>