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Full Protection (full + protection)
Selected AbstractsMice protected by oral immunization with Lactobacillus reuteri secreting fusion protein of Escherichia coli enterotoxin subunit proteinFEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 3 2007Chi-Ming Wu Abstract A green fluorescent protein (gfp) gene was ligated to the Lactobacillus reuteri -specific nisin-inducible expression-secretion vector pNIES, generating a pNIES-GFP vector capable of secreting the cloned gene as a GFP-fusion protein with fluorescent activity. To develop this system as a live vehicle carrying the heat-stable enterotoxin (ST) and heat-labile enterotoxin B (LTB) of the enterotoxigenic Escherichia coli (ETEC), a recombinant 5,- ST - LTB -3, DNA fragment was cloned into pNIES-GFP. The resulting L. reuteri/pNIES-GFP:STLTB system was found to possess the capability of adhering to the mice gut, secreting GFP:STLTB product at 0.14 and 0.026 pgcell,1 under induced and noninduced conditions, respectively. Further analysis of the GFP:STLTB product confirmed its ganglioside-binding ability, LTB antigenicity and relative freedom from the ST-associated toxicity, making it suitable for use as an oral vaccine in mice. Oral inoculation of the L. reuteri/pNIES-GFP:STLTB culture in mice elicited significant (P<0.01) serum IgG and mucosal IgA antibodies against the STLTB antigen. These immunized mice were subsequently challenged with ETEC and showed full protection against the fluid influx response in the gut. This is the first report of using L. reuteri as a vaccine carrier to induce complete immunologic protection against ETEC. [source] Protection against acetaminophen hepatotoxicity by clofibrate pretreatment: Role of catalase induction,JOURNAL OF BIOCHEMICAL AND MOLECULAR TOXICOLOGY, Issue 5 2002Chuan Chen Abstract Mice pretreated with the peroxisome proliferator clofibrate (CFB) are highly resistant to acetaminophen (APAP)-induced hepatotoxicity. The objective of the present study was to investigate whether the increase in hepatic catalase activity following CFB pretreatment plays a role in this hepatoprotection. An irreversible inhibitor, 3-amino-1,2,4-triazole (3-AT), was used to modulate catalase activity. Hepatic catalase activity in mice pretreated with CFB (500 mg/kg, i.p., for 10 days) was significantly inhibited by 3-AT (100 or 500 mg/kg, i.p.). In addition, the lower dose of 3-AT (100 mg/kg) had minimal effect on biliary and urinary excretion of APAP metabolites generated from a nontoxic dose, suggesting that APAP metabolism was not modulated by this dose of 3-AT. The mortality rate of corn-oil-pretreated mice challenged with APAP (800 mg/kg, p.o.) was significantly increased by 3-AT (100 mg/kg, i.p.) given 1 h before APAP. As expected, CFB pretreatment conferred full protection against APAP-induced hepatotoxicity. The same 3-AT treatment, however, did not abolish hepatoprotection in CFB-pretreated mice, despite the marked inhibition of hepatic catalase activity. In conclusion, these results indicate that elevated catalase activity in mice exposed to CFB does not appear to mediate the hepatoprotection, suggesting that other cellular defense mechanisms are involved. © 2002 Wiley Periodicals, Inc. J Biochem Mol Toxicol 16:227,234, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.10043 [source] THE AMBIGUITY OF THE EMBRYO: ETHICAL INCONSISTENCY IN THE HUMAN EMBRYONIC STEM CELL DEBATEMETAPHILOSOPHY, Issue 2-3 2007KATRIEN DEVOLDER Abstract: We argue in this essay that (1) the embryo is an irredeemably ambiguous entity and its ambiguity casts serious doubt on the arguments claiming its full protection or, at least, protection against its use as a means for stem cell research, (2) those who claim the embryo should be protected as "one of us" are committed to a position even they do not uphold in their practices, (3) views that defend the protection of the embryo in virtue of its potentiality to become a person fail, and (4) the embryo does not have any rights or interests to be protected. Given that many are willing to treat the embryo as a means in other practices, and that human embryonic stem cell (hESC) research holds great potential to benefit many people, one cannot but conclude that hESC research is permissible and, because of its immense promise for alleviating human suffering, even obligatory. [source] DNA vaccination against foot-and-mouth disease via electroporation: study of molecular approaches for enhancing VP1 antigenicityTHE JOURNAL OF GENE MEDICINE, Issue 9 2006Suk-Am Kim Abstract Background Foot-and-mouth disease virus (FMDV) affects susceptible livestock animals and causes disastrous economic impact. Immunization with plasmid expressing VP1 that contains the major antigenic epitope(s) of FMDV as cytoplasmic protein (cVP1) failed to elicit full protection against FMDV challenge. Materials and methods In this study, mice were immunized via electroporation with four cDNA expression vectors that were constructed to express VP1 of FMDV, as cytoplasmic (cVP1), secreted (sVP1), membrane-anchored (mVP1) or capsid precursor protein (P1), respectively, to evaluate whether expression of VP1 in specific subcellular compartment(s) would result in better immune responses. Results Electroporation enhanced immune responses to vectors expressing cVP1 or P1 and expedited the immune responses to vectors expressing sVP1 or mVP1. Immunization of mice via electroporation with mVP1 cDNA was better than sVP1 or cVP1 cDNA in eliciting neutralizing antibodies and viral clearance protection. Vaccination with P1 cDNA, nonetheless, yielded the best immune responses and protection among all four cDNAs that we tested. Conclusions These results suggest that the antigenicity of a VP1 DNA vaccine can be significantly enhanced by altering the cellular localization of the VP1 antigen. Electroporation is a useful tool for enhancing the immune responses of vectors expressing VP1 or P1. By mimicking FMDV more closely than that of transgenic VP1 and eliciting immune responses favorably toward Th2, transgenic P1 may induce more neutralizing antibodies and better protection against FMDV challenge. Copyright © 2006 John Wiley & Sons, Ltd. [source] Surface-exposed expression of Edwardsiella tarda EseB in live attenuated Vibrio anguillarum based on novel surface display systemsAQUACULTURE RESEARCH, Issue 13 2009Qiyao Wang Abstract Live, attenuated Vibrio anguillarum strains can serve as vectors for the delivery of heterologous antigens for development of multivalent recombinant vaccines. Based on the outer membrane anchoring elements of V. anguillarum, we have previously constructed several efficient surface display systems Lpp-Omporf1, Lpp-OmpU, Lpp-Omp26La, Wza-Omporf1, Wza-OmpU and Wza-Omp26La. In this study, with these constructed surface display systems, a putative antigen protein EseB from pathogenic Edwardsiella tarda was successfully expressed on the surface of an attenuated V. anguillarum strain to get multivalent vaccine candidates. Further immune protection evaluation in zebra fish (Danio rerio) demonstrated that the V. anguillarum EseB-display strain AV/pW-26La-B could trigger full protection against V. anguillarum infection and early protection against E. tarda infection in the immunized fish. These results suggest that surface display of heterologous protective antigens in attenuated V. anguillarum could be used as a tool to develop potential V. anguillarum vector vaccine. [source] The protective role of Visudyne eyeglass® against VEGF synthesis after photodynamic therapy with verteporfinACTA OPHTHALMOLOGICA, Issue 8 2009Peykan Türkçüo Abstract. Purpose:, We aimed to determine the extent of protection provided by Visudyne eyeglass® against vascular endothelial growth factor (VEGF) synthesis following photodynamic therapy (PDT). Methods:, Three groups with 14 rabbits in each were established. These consisted of a control (dextrose infusion) group, an infusion (verteporfin infusion) group and an irradiation (verteporfin infusion + irradiation) group. One eye in each animal was closed with Visudyne eyeglass® and the other by eyelid sutures. The rabbits were exposed to daylight for 30 mins at 2 and 48 hours after the infusion was administered. Half the animals in each group were killed on day 5. The remaining animals were killed on day 10. Levels of VEGF in homogenized retina and choroids were analysed with an ELISA (enzyme-linked immunosorbent assay). Results:, Mean VEGF levels, in pg/mg protein, on days 5 and 10 in the control + glass, control + suture, infusion + glass, infusion + suture, irradiation + glass and irradiation + suture subgroups were, respectively: 1.69 ± 0.67, 1.91 ± 0.44; 1.75 ± 0.69, 1.93 ± 0.53; 2.30 ± 0.77, 3.47 ± 2.02; 1.90 ± 1.00, 2.93 ± 0.16; 4.39 ± 2.74, 13.63 ± 5.25; 3.38 ± 1.05, 7.37 ± 2.12. On day 10, VEGF levels were significantly higher in the infusion and irradiation groups compared with the control group (p < 0.05). There were no statistically significant differences between glass and suture samples on days 5 and 10 in the infusion group, or on day 5 in the irradiation group. However, on day 10, the mean VEGF level in eyes closed with Visudyne eyeglass® in the irradiation group was significantly higher than in sutured eyes (p = 0.011). Conclusions:, Visudyne eyeglass® offers full protection against VEGF increases caused by verteporfin infusion but is only partially protective in eyes exposed to sensitizing light. [source] | ||||||||||