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Objective:To study the method of measuring iodine content in urine with automatic iodine element analyzer.Methods:The iodine content in urine was measured by automatic iodine element analyzer DAT-50S, and the applicability of the method was tested, including the standard curve and detection limit, precision test, standard substance determination test, standard addition recovery test, and method comparison test.Results:Within the range of iodine content 0 - 800 μg/L, the correlation coefficient of the standard curve was - 0.999 7, and the detection limit was 6.2 μg/L. Precision: the relative standard deviation ( RSD) values of three urine samples with low, medium and high iodine contents within the range of the standard curve were 1.6%, 1.1% and 0.7%, respectively ( n = 8). Accuracy: the measured values of two urine iodine standard substances measured by the automatic iodine element analyzer were all within the reference value range; the average recovery rate of three urine samples with low, medium and high iodine contents within the range of the standard curve was 99.6%, and the recovery rate ranged from 97.6% to 101.2%. Method comparison test: there was no statistically significant difference between the results of 20 urine samples determined by arsenic-cerium catalytic spectrophotometry (WS/T 107.1-2016) and the automatic iodine element analyzer ( t = 0.984, P > 0.05). Conclusion:The precision and accuracy of urinary iodine determination using the automatic iodine element analyzer are high, the operation is simple, and it is suitable for popularization and application in grassroots disease control institutions.
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Toll-like receptor 4 (TLR4), a type Ⅰ transmembrane protein, has been extensively studied in the Toll-like receptor family at present. TLR4 ligands include lipopolysaccharides ( LPS) present in the outer membrane of gram-negative bacteria and monophosphoryl lipid A ( MPLA) which is a derivative of LPS. TLR4 agonists, alone, as a major component of compound adjuvants or in combination with other TLRs agonists, have been widely used as adjuvants in various vaccines and demonstrated great potential in vaccine development. This review addressed the discovery, application, features and prospect of novel vac-cine adjuvants based on TLR4 agonists, aiming to provide reference for rational use of adjuvants and further development.
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Objective To compare the adjuvant activity of oil-in-water emulsion MF59 and aluminum hydroxide on immune responses to HIV-1 multi-epitope protein MEP1 in BALB/c mice. Methods HIV-1 multi-epitope protein MEP1 with MF59 or aluminum was prepared to intramuscularly vaccinate female BALB/c mice for three times. Serum and splenocytes were isolated from the mice 10 d after the first and last vaccination. Specific anti-MEP1 antibodies and the subclasses in serum were detected by ELISA. The num-bers of splenic lymphocytes secreting IFN-γ and IL-4 were measured by ELISPOT. Differences in humoral and cellular immune responses induced by the two different adjuvants were compared. Results After a sin-gle-dose immunization, aluminum adjuvant promoted early humoral and cellular immune responses to MEP1 compared with MF59. After the three-dose immunization, both aluminum adjuvant and MF59 promoted MEP1 to induce Th2-biased humoral immune response, while MF59 also enhanced a balanced Th1/Th2 cel-lular immune response. Conclusions Aluminum adjuvant was a more suitable adjuvant than MF59 for HIV-1 multi-epitope protein MEP1.
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Objective To express a recombinant protein TFPR1 ( the functional region of the snake venom proteins from Trimeresurus flavoviridis) in Pichia pastoris expression system. Methods The target gene was codon-optimized and synthesized according to the sequence of the conserved structural do-main of triflin and then cloned into the Pichia pastoris expression vector pPICZαA to construct the recombi-nant expression plasmid pPICZαA-TFPR1. The recombinant plasmid pPICZαA-TFPR1 was electroporated into the yeast strain X33. The transformed strains carrying expression plasmid were screened out with Zeocin and then induced by methanol to express the recombinant protein TFPR1. ELISA was performed for the screening of positive clones. SDS-PAGE and Western blot were used for further identification of the ex-pressed products. Results The recombinant plasmid pPICZαA-TFPR1 was successfully constructed. The recombinant protein TFPR1 was expressed in a secreted form at a molecular weight of 16×103. Conclusion The recombinant protein TFPR1 was successfully expressed in Pichia pastoris expression system, which laid a foundation for further researches on its biological function and application as an adjuvant.
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Objective To analyze and compare the pathological changes of lung tissue in mice infected with the novel H7N9 influenza virus and 2009 pandemic H1N1 influenza virus, respectively, and to preliminarily study the mecha-nisms of acute lung injury induced by those virus infection .Methods SPF 6-week old BALB/c mice ( body weight 18-20 g, male∶female=1∶1) (n=3 in each subgroup) were intranasally infected with H7N9 virus and H1N1 virus, respec-tively.The behavior and survival time of mice after virus infection were observed and the survival rates were analyzed .The heart, liver, spleen, lung, kidney, intestines, and brain were collected at indicated time points for histopathological exami-nation using H&E staining .The distribution of virus antigen was detected by immunohistochemistry .The neutrophil infiltra-tion was also observed .The correlation of lung injury with virus replication and host immune responses was analyzed .Re-sults The lung and spleen injury of mice infected with H 7N9 virus was slighter and their survival rate (100%) was high-er than those of mice infected with H1N1 virus.The damages of the lung and spleen in H1N1virus-infected mice were more severe than that in H7N9 virus-infected mice, and all the 10 mice in this group died within 9 days after virus inoculation . The distributions of both the virus antigens were mainly in the bronchial epithelial cells , a few stromal cells and alveolar ep-ithelial cells .The levels of virus replication in the two groups were not significantly different .There were more intense neu-trophil infiltration in the lung and inflammatory response in the H 1N1 virus-infected mice than those in the H7N9 virus-in-fected mice .Conclusions There are some differences of the pathological characteristics and extent of lung injury in the mice infected with H7N9 virus and H1N1 virus, respectively.The virus replication is a precipitating factor but not the deci-sive factor of the lung injury , and there is a close relationship between the host immune responses and acute lung injury .
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Objective To obtain Chinese hamster ovary (CHO) cell lines that stably express a targeting complement inhibitor CR2-CD59.Methods The recombinant plasmid PEE14.1-CR2-CD59 was constru-cted by cloning the DNA fragment CR2-CD59 into plasmid PEE14.1,and the obtained plasmid was transfected into CHO cells by FuGENE 6.The clones with stable high expression of target fragment were selected by methionine sulfoximine (MSX),the expression of CR2-CD59 was analyzed by ELISA,SDS-PAGE and Western blotting analysis.Results Several stable expression clones were obtained,and CR2-CD59 was highly expressed in the secret form in CHO cells.SDS-PAGE analysis showed that the molecular weight of the recombined protein CR2-CD59 was consistent with the predicted one.ELISA and Western blotting results revealed that the CR2-CD59 could react with both anti-human CR2 and anti-human CD59 polyclonal antibodies.Compared with serum-containing medium,the protein was highly expressed in serum-free medium (P
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Objective:To investigate the immume mechanism and protective effect of DNA vaccine pcD flaB against pathogenic leptospira infection. Methods: DNA vaccine pcD flaB was constructed by inserting flaB into the eucaryotic expressing plasmid pcDNA3. After guinea pigs were infected with leptospira, the protective rate was observed and specific anti leptospira antibody IgG were tested by ELISA. TNF activity was tested by cell proliferation. Results:The protective rate against leptospira infection was 100%. The specific antibody IgG generated peaked at the 6th week. Activity of TNF released by macrophage of guinea pigs given DNA vaccine was higher than that not given vaccine. Conclusion:DNA vaccine pcD flaB can protect guinea pigs from leptospira challenge infection by inducing humoral immune response and increasing TNF activity.