[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.

[Construction and analysis of a breast cancer gene-drug network model].

OBJECTIVE: To construct a breast cancer gene-drug network model for extracting and predicting the correlations between breast cancer-related genes and drugs. METHODS: We developed an algorithm based on the ABC principle and the association rules to obtain the correlations between the biological entities. For breast cancer, we constructed 3 different correlations (gene-gene, drug-drug and gene-drug) and used the R language to implement the associated network model. The reliability of the algorithm was verified by ROC curve. RESULTS: We identified 185 breast cancer-associated genes and 98 associations between them, 97 drugs and 170 associations between them. The breast cancer genes-drugs network contained 127 genes and 77 drugs with 384 associations between them. CONCLUSIONS: We identified a large number of different correlations between the breast cancer-related genes and drugs and close correlations between some biological entity pairs that have not yet been reported, which may provide a new strategy for experimental design for testing personalized breast cancer treatment.

[In vitro killing of Trichinella spiralis muscle larvae by exogenous nitric oxide from SNP].

OBJECTIVE: To study the lethal effect of exogenous nitric oxide donor sodium nitroprusside (SNP) on the muscle larvae of Trichinella spiralis in vitro cultivation. METHODS: T. spiralis muscle larvae isolated from the infected BALB/c mice were formulated into a 1,000 larva/ml suspension with RPMI 1640 medium, and 0.1 ml suspension per orifice was cultured with SNP at 37°C in a humidified 5% CO2 atmosphere. The final concentrations of SNP were 0.02, 0.05, 0.10, 0.20, 0.50 and 1.00 mmol/L, respectively, and then the experiments were divided into 5 groups:1.00 mmol/L SNP (control group, Group A), 0.15 mmol/L FeSO4+ 1.00 mmol/L SNP (Group B), 1.00 mmol/L L-cysteine + 1.00 mmol/L SNP (Group C), 0.15 mmol/L FeSO4+ 1.00 mmol/L L-cysteine + 1.00 mmol/L SNP (Group D) and 0.15 mmol/L Hemoglobin + 1.00 mmol/L SNP (Group E). All the groups were incubated with T. spiralis muscle larvae in RPMI 1640 medium. The survivability of the muscle larvae was observed by steromicroscope and the differences of inhibition ratio among these groups were analyzed 4 d after the incubation. Results SNP 0.02 mmol/L was not cytotoxic to the muscle larvae with an inhibition of (5.50 ± 1.80) %. The mortality rates of SNP 0.05, 0.10, 0.20, 0.50, 1.00 mmol/L groups were (20.19±2.71)%, (29.21±2.12)%, (41.81±2.03)%, (47.85±3.79)%, (60.98±5.19)%, respectively, significantly higher than that of the control group[(4.93±0.25) %, all P < 0.051]. There was a positive liner correlation between the mortality of muscle larvae and SNP concentrations in the range of 0.02-1.00 mmol/L. Next, Group A, B, C, D and E led to the mortalities from (60.98±5.19)% to (49.48±1.34)%, (47.29±2.79)%, (26.28±1.37)%, (17.93±3.49)%, respectively, and all the differences between Group A and the other four groups were statistically significant (all P < 0.05). CONCLUSIONS: Exogenous nitric oxide released from SNP can kill the muscle larvae of T. spiralis. However, hemoglobin, L-cysteine, and FeSO4 can reverse the lethal effect on the parasites. The best inhibitor was hemoglobin.

Optimized codon usage enhances the expression and immunogenicity of DNA vaccine encoding Taenia solium oncosphere TSOL18 gene.

Cysticercosis due to larval cysts of Taenia solium, is a serious public health problem affecting humans in numerous regions worldwide. The oncospheral stage-specific TSOL18 antigen is a promising candidate for an anti-cysticercosis vaccine. It has been reported that the immunogenicity of the DNA vaccine may be enhanced through codon optimization of candidate genes. The aim of the present study was to further increase the efficacy of the cysticercosis DNA vaccine; therefore, a codon optimized recombinant expression plasmid pVAX1/TSOL18 was developed in order to enhance expression and immunogenicity of TSOL18. The gene encoding TSOL18 of Taenia solium was optimized, and the resulting opt-TSOL18 gene was amplified and expressed. The results of the present study showed that the codon-optimized TSOL18 gene was successfully expressed in CHO-K1 cells, and immunized mice vaccinated with opt-TSOL18 recombinant expression plasmids demonstrated opt­TSOL18 expression in muscle fibers, as determined by immunohistochemistry. In addition, the codon-optimized TSOL18 gene produced a significantly greater effect compared with that of TSOL18 and active spleen cells were markedly stimulated in vaccinated mice. 3H-thymidine incorporation was significantly greater in the opt-TSOL18 group compared with that of the TSOL18, pVAX and blank control groups (P<0.01). In conclusion, the eukaryotic expression vector containing the codon-optimized TSOL18 gene was successfully constructed and was confirmed to be expressed in vivo and in vitro. The expression and immunogenicity of the codon-optimized TSOL18 gene were markedly greater compared with that of the un-optimized gene. Therefore, these results may provide the basis for an optimized TSOL18 gene vaccine against cysticercosis.

[Deltamethrin resistance, metabolic detoxification enzyme and kdr mutation in Anopheles sinensis in region along Huaihe River in Anhui Province].

OBJECTIVE: To understand the deltamethrin resistance level, GTS and P450 metabolic detoxification enzyme activities, and mutations in the para-type sodium channel gene that confers knockdown resistance (kdr) in Anopheles sinensis mosquitoes from malaria endemic areas along the Huaihe River in Anhui Province, China. METHODS: An. sinensis adult mosquitoes were collected in Lilou, Mohekou and Tuohu townships of Bengbu City, Anhui Province from August to September, 2011. The insecticide resistance bioassays were performed on adult mosquitoes by using the standard WHO susceptibility test with diagnostic concentrations of deltamethrin 0.05%, and the mosquito resistance status was classified based on the WHO resistance classification criteria. The metabolic detoxification enzyme activities were measured in randomly selected mosquitoes, and the IIS6 region of the para-type sodium channel gene was amplified by PCR and sequenced to detect mutations at the codon 1014. RESULTS: The knockdown rates within 60 min exposure to deltamethrin test paper were 4.1%, 7.0% and 8.2%, and the mortality rates were 8.2%, 12.0% and 12.8% for mosquitoes collected from Lilou, Mohekou and Tuohu townships, respectively. These three populations were classified as highly resistant populations based on the WHO resistance classification criteria. The GST and P450 enzyme activities of the three populations were significantly higher than those of the susceptible laboratory population (P < 0.001). L1014C and L1014F mutations were detected, and the wild type homozygote kdr genotype was not found. These three populations exhibited a small but insignificant difference in kdr allele frequencies. No mutation was found in the laboratory susceptible mosquitos. CONCLUSION: The An. sinensis mosquito populations from the regions along the Huaihe River in Anhui Province are strongly resistant to pyrethroid insecticides, and exhibit significantly higher metabolic detoxification enzyme activities than the laboratory susceptible population. The high frequency of kdr mutation is identified in the mosquito populations from the region along the Huaihe River in Anhui Province, China.

Functional characterization of an arrestin gene on insecticide resistance of Culex pipiens pallens.

BACKGROUND: Continuous and excessive application of insecticides has resulted in the rapid development of insecticide resistance in several mosquito species, including Culex pipiens pallens. Previous studies in our laboratory found that arrestin gene expression was higher in the deltamethrin-resistant (DR) strain than in the deltamethrin-susceptible (DS) strain of Cx. pipiens pallens. Similarly, other studies reported that arrestin was highly expressed in permethrin-resistant Cx. quinquefasciatus and in dichlorodiphenyltrichloroethane (DDT)-resistant Drosophila melanogaster. METHODS: Full-length cDNAs of an arrestin gene were cloned from Cx. pipiens pallens via polymerase chain reaction (PCR) and rapid amplification of cDNA end (RACE). The mRNA levels of the arrestin gene in the whole life cycle of DR and DS strains of Cx. pipiens pallens were investigated via quantitative real-time PCR. In addition, the relationship between arrestin and deltamethrin (DM) resistance were identified using genetic overexpression strategies and arrestin RNAi in mosquito cells. Cell viability was analyzed with cholecystokinin octapeptide after DM treatment. Moreover, the mRNA levels of cytochrome P450 6A1 (CYP6A1) and opsin in the transfected cells and controls were analyzed. RESULTS: Complete arrestin gene sequence was cloned and expressed throughout the life cycle of Cx. pipiens pallens. Moreover, arrestin was significantly upregulated in the DR strain, compared with that in the DS strain at the egg, pupae, and adult stages. Arrestin overexpression comparably increased the mosquito cell viability, whereas arrestin knockdown by siRNA decreased mosquito cell viability with deltamethrin (DM) treatment. Meanwhile, the mRNA levels of CYP6A1 and opsin were upregulated in mosquito cells transfected with arrestin and downregulated in mosquito cells with arrestin knockdown. CONCLUSION: This study presented the first evidence that arrestin might be associated with insecticide resistance in Cx. pipiens pallens.

[Prediction and identification of Taenia solium oncosphere TSO45-4B antigen FnIII structure domain linear B cell epitopes].

OBJECTIVE: To predict and identify Taenia solium oncosphere TSO45-4B antigen Fn III structure domain linear B cell epitopes. METHODS: The B cell epitopes of TSO45-4B Fn III structure domain were predicted through the sequence analysis by using bioinformatics online tools and the protein space conformation was predicted by SWISS-MODEL. The peptides were synthesized according to the predicted linear epitopes. The immunoreactivity of sera of cysticercosis patients to the peptides synthesized was tested by using ELISA. RESULTS: Two linear B cell epitopes of TSO45-4B Fn III structure domain were predicted, and one of the predicted epitope peptides synthesized could be recognized by the sera of cysticercosis patients. CONCLUSION: Two linear B cell epitopes of TSO45-4B Fn III structure domain are predicted and one of them has been confirmed successfully.