[Component analysis of excretory/secretory protein from Trichinella spiralis adult worm].

Objective: To analyze the component of adult worm excretory/secretory protein(AWESP) from Trichinella spiralis using the shotgun method, and find out the active component underlying its regulatory effect on colitis in humans. Methods: The T. spiralis AWESP was prepared, separated by SDS-PAGE, lysed with trypsin, and analyzed by shotgun LC-MS/MS. The protein components were determined with the Masco software and classified using the Gene Ontology(GO) method in cellular components, molecular functions, and biological processes. Results: The AWESPs isolated by SDS-PAGE had a Mr of 15 000-116 000. A total of 280 proteins were revealed by LC-MS/MS, of which 96 were identified by Masco software, 98 were putative, and the remaining 86 were unclear. Preliminary results showed that 4 proteins had regulatory potential for colitis, including cysteine protease inhibitor, serine protease, 53 000 excretory/secretory antigen, and glutathione-S-transferase. GO enrichment analysis showed that the identified proteins had 104 different molecular functions, involved in 363 biological processes. Conclusion: As revealed by the Masco software, T. spiralis AWESP has complex components and 96 have been identified in this study. Four of them are preliminarily shown to be associated with the anti-colitis effect of T. spiralis.

[Role of CD8+ T cells in the tumor growth delay induced by Toxoplasma gondii excreted-secreted antigen in B16F10 mouse melanoma model].

OBJECTIVE: To observe the role of CD8+ T cells in the tumor growth delay induced by Toxoplasma gondii excreted-secreted antigens (TgESA) in B16FI0 mouse melanoma model in the early stage. METHODS: TgESA were prepared by incubating T. gondii tachyzoites for 12 h in vitro. 15 C57BL/6 mice were randomly assigned to group A, B, and C (5 mice per group). Each mouse in group B and C was subcutaneously injected in right flank with 2 x 10(5) B16F10 cells. Mice in group C were intraperitoneally injected with TgESA (100 microl per mouse) at 7d after B16F10 cells injection. Mice of group A were only injected with PBS. On the 13th day after melanoma cell injection, the mice were sacrificed and spleen was removed. The percentage of CD8+ T cells in the spleen was analyzed by flow cytometry. CD8+ T cells were isolated from spleen cells by using immunomagnetic beads. The activity of CD8+ T cells against B16F10 melanoma cells was determined by LDH release assay at different effect-to-target cell ratios (2.5:1, 5:1, and 10:1). Other 30 C57BL/6 mice were randomly divided into group E, F, and G. Each mice were injected with 2 x 10(5) B16F10 cells. At the same time, mice in group F and G were simultaneously injected via the tail vein with CD8+ T cells isolated from mice in group B and C. Tumor growth, mortality and survival time of mice were observed and recorded during 35-d observation period. RESULTS: The percentage of CD3+CD8+T cells in the spleen cells of group C [(15.74 +/- 0.28)%] was significantly higher than that of group B [(14.18 +/- 0.27)%] and A [(13.86 +/- 0.13)%] (P < 0.05). At different effect-to-target cell ratios, the activity of CD8+ T cells against B16F10 cells in group C was significantly higher than that of group B (P < 0.05). The average time of tumor formation in group G [(14.9 +/- 1.2) d] was longer than that in group F [(11.9 +/- 0.7) d] and E [(9.4 +/- 1.2) d] (P < 0.05). The tumor size in these groups increased, but there was no obvious difference in the tumor growth rate among the three groups. The tumor size of group G was significantly smaller than the other two groups (P < 0.05). In group E, F and G, mice began to die on the 26th day, the 29th day and the 30th day after tumor inoculation, and the number of survival mice was 3, 5 and 7, respectively, at the 35th day after injection. CONCLUSIONS: TgESA may up-regulate the quantity and function of CD8+ T cell in B16F10 melanoma mouse model, which plays a role of delaying tumor growth in early stage.