1.T Regulatory Cell Responses to Immunization with a Soluble Egg Antigen in Schistosoma mansoni-Infected Mice.
Eman EL-AHWANY ; Ibrahim Rabia BAUIOMY ; Faten NAGY ; Rabab ZALAT ; Ola MAHMOUD ; Suher ZADA
The Korean Journal of Parasitology 2012;50(1):29-35
The aim of the study is to characterize the phenotypes of CD4+ CD25+ T regulatory cells within the liver granulomas and association with both Foxp-3 gene expression and splenic cytokines. Naive C57BL/6 mice were intravenously injected with multiple doses of the soluble egg antigen (SEA) 7 days before cercarial infection. The immunized and infected control groups were sacrificed 8 and 16 weeks post-infection (PI). Histopathology, parasitological parameters, splenic phenotypes for T regulatory cells, the FOXP-3 expression in hepatic granuloma using real-time PCR, and the associated splenic cytokines were studied. Histopathological examination of the liver revealed remarkable increase in degenerated ova within hepatic granuloma which decreased in diameter at weeks 8 and 16 PI (P<0.01). The percentage of T regulatory cells (CD4+ CD25+) increased significantly (P<0.01) in the immunized group compared to the infected control at weeks 8 and 16 PI. The FOXP-3 expression in hepatic granulomas increased from 10 at week 8 to 30 fold at week 16 PI in the infected control group. However, its expression in the immunized group showed an increase from 30 at week 8 to 70 fold at week 16 PI. The splenic cytokine levels of pro-inflammatory cytokines, IFN-gamma, IL-4, and TNF-alpha, showed significant decreases (P<0.05) compared to the infected control group. In conclusion, the magnitude and phenotype of the egg-induced effects on T helper responses were found to be controlled by a parallel response within the T regulatory population which provides protection in worm parasite-induced immunopathology.
Animals
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Antibodies, Helminth/immunology
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Antigens, Helminth/administration & dosage/*immunology
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Cytokines/genetics/immunology
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Forkhead Transcription Factors/genetics/immunology
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Granuloma/*immunology/parasitology
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Humans
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Immunization
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Mice
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Mice, Inbred BALB C
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Schistosoma mansoni/genetics/*immunology
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Schistosomiasis mansoni/genetics/*immunology/parasitology
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Spleen/immunology
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T-Lymphocytes, Regulatory/*immunology
2.Protective and Anti-Pathology Effects of Sm Fructose-1,6-Bisphosphate Aldolase-Based DNA Vaccine against Schistosoma mansoni by Changing Route of Injection.
Mohamed SABER ; Tarek DIAB ; Olft HAMMAM ; Amr KARIM ; Amina MEDHAT ; Mamdouh KHELA ; Ehab EL-DABAA
The Korean Journal of Parasitology 2013;51(2):155-163
This study aimed to evaluate the efficacy of fructose-1,6-bis phosphate aldolase (SMALDO) DNA vaccination against Schistosoma mansoni infection using different routes of injection. The SMALDO has been cloned into the eukaryotic expression vector pcDNA3.1/V5-His TOPO-TA and was used in injecting Swiss albino mice intramuscularly (IM), subcutaneously (SC), or intraperitoneally (IP) (50 microg/mouse). Mice vaccinated with non-recombinant pcDNA3.1 served as controls. Each group was immunized 4 times at weeks 0, 2, 4, and 6. Two weeks after the last booster dose, all mice groups were infected with 80 S. mansoni cercariae via tail immersion. At week 8 post-infection, animals were sacrificed for assessment of parasitological and histopathological parameters. High anti-SMALDO IgG antibody titers were detected in sera of all vaccinated groups (P<0.01) compared to the control group. Both the IP and SC vaccination routes resulted in a significant reduction in worm burden (46.2% and 28.9%, respectively, P<0.01). This was accompanied by a significant reduction in hepatic and intestinal egg counts (41.7% and 40.2%, respectively, P<0.01) in the IP group only. The number of dead eggs was significantly increased in both IP and IM groups (P<0.01). IP vaccination recorded the highest significant reduction in granuloma number and diameter (54.7% and 29.2%, respectively, P<0.01) and significant increase in dead miracidia (P<0.01). In conclusion, changing the injection route of SMALDO DNA vaccination significantly influenced the efficacy of vaccination. SMALDO DNA vaccination via IP route could be a promising protective and anti-pathology vaccine candidate against S. mansoni infection.
Animals
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Antibodies, Helminth/blood
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Disease Models, Animal
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Female
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Fructose-Bisphosphate Aldolase/genetics/*immunology
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Histocytochemistry
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Immunoglobulin G/blood
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Injections, Intramuscular
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Injections, Intraperitoneal
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Injections, Subcutaneous
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Mice
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Parasite Load
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Schistosoma mansoni/enzymology/genetics/*immunology
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Schistosomiasis mansoni/immunology/parasitology/pathology/*prevention & control
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Vaccination/methods
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Vaccines, DNA/administration & dosage/genetics/*immunology
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Vaccines, Synthetic/administration & dosage/genetics/immunology