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- Akhiani, Aliasghar, 1957, et al.
(author)
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Comparative antigen analysis of different life stages of Schistosoma mansoni by crossed immunoelectrophoresis
- 1991
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In: Int Arch Allergy Appl Immunol. ; 95:2-3, s. 266-72
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Journal article (peer-reviewed)abstract
- Two-dimensional (crossed) immunoelectrophoresis was used for analysis of soluble antigen extracts obtained from the three developmental stages, cercariae, adult worms and eggs, of Schistosoma mansoni by using homologous hyperimmune sera produced in sheep. The antigenic relationships between the three stages as well as the possible relationship to the intermediate snail host were studied. Seven antigen components were shown to be shared between all three life stages of S. mansoni. Furthermore, one antigen was common to adult worm and snail, and one other antigen was shared between cercaria and snail. By using an intermediate gel containing lectin in the antigen-antibody system or by enzyme staining of the immune precipitates it was possible to identify schistosome antigens possessing lectin reactivity or enzyme activity. Characterization of enzyme activities revealed three individual precipitating antigens in adult worm of S. mansoni possessing esterase, leucyl-glycyl-glycine peptidase and phenylalanyl-leucine peptidase activities, respectively. One further precipitinogen with malate dehydrogenase activity was identified for all three life stages.
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- Akhiani, Aliasghar, 1957, et al.
(author)
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Effect of cholera toxin on vaccine-induced immunity and infection in murine schistosomiasis mansoni
- 1993
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In: Infect Immun. ; 61:11, s. 4919-24
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Journal article (peer-reviewed)abstract
- Intradermal vaccination of mice with soluble adult worm antigen (SWAP) in combination with Mycobacterium bovis BCG (Swedish strain) induced significant protection against subsequent infection with Schistosoma mansoni cercariae. When cholera toxin (CT) was used as an adjuvant in combination with SWAP or fraction A, no significant protection was observed. However, intradermal vaccination in combination with CT triggered a strong anti-SWAP antibody response and induced a strong delayed-type hypersensitivity response to schistosome antigens (SWAP or fraction A), one significantly higher than that in the SWAP-BCG group. In addition, vaccinating mice intranasally with SWAP or cercarial antigen together with CT as adjuvant failed to induce any significant protection. Surprisingly, mice given CT alone intranasally revealed a significantly enhanced worm burden. These findings suggest that mucosal application of CT may modulate the host-parasite relationship in favor of parasite survival.
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- Akhiani, Aliasghar, 1957, et al.
(author)
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Immunological cross reactivity between Schistosoma mansoni and cholera toxin
- 1997
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In: Parasite Immunol. ; 19:8, s. 355-61
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Journal article (peer-reviewed)abstract
- Intranasal administration of schistosome antigens in combination with appropriate adjuvant may be an effective route for immunization against schistosomes, since the lungs represent an important site of elimination of schistosomulae. Our previous studies have shown that in mice intranasal administration of cholera toxin (CT) before infection with Schistosoma mansoni results in an enhancement of the worm burden in comparison to nontreated infected animals. In the present study, it was shown that mice treated intranasally with CT displayed high numbers of schistosome-reactive IgM-secreting cells in the spleen as well as high levels of schistosome-reactive serum IgM antibodies, whereas no significant immunological response against two other antigens, ovalbumin (OVA) or keyhole limpet haemocyanin (KLH) was noted. Sera from mice treated intranasally with CT recognized a 22 kDA antigen on SWAP blots. This band was not demonstrable after absorption of the sera with SWAP. These findings indicate a possible cross reactivity between cholera toxin and schistosome antigens. Further analysis by Western blot revealed that a 22 kDa antigen was detected on CT blots by sera from mice and humans infected with S. mansoni. This band was not demonstrable after absorption of the mouse or the human sera with CT. The 22 kDa cross reactive antigen was heat-stable. The antibodies against the 22 kDa antigen were only found within the IgM class but not within other Ig isotypes. Our findings also indicate that the 22 kDa antigen detected by anti-S. mansoni antibodies represents the A1 fragment of the cholera toxin.
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4. |
- Akhiani, Aliasghar, 1957, et al.
(author)
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Intranasal administration of Schistosoma mansoni adult worm antigen in combination with cholera toxin induces a Th2 cell response
- 1997
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In: Parasite Immunol. ; 19:4, s. 183-90
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Journal article (peer-reviewed)abstract
- Mice immunized with soluble adult worm antigen (SWAP) in combination with cholera toxin (CT) displayed significantly larger numbers of IgG1, IgM and IgA secreting cells in the spleen and in the lungs as compared to mice which had received SWAP only. The ratio of SWAP-specific IgG1 to IgG2a antibody-secreting spleen cells was also significantly higher in the SWAP-CT group. Analysis of cytokine responses revealed that SWAP-stimulated spleen and lung cells from the SWAP-CT group produced lower levels of IFN-gamma but higher levels of IL-4 and IL-5 as compared to cells from the SWAP group. These findings indicate that intranasal administration of SWAP-CT induces a Th2 cell response in the spleen and in the lungs. Our findings also suggest that CT was responsible for induction of this Th2 cell response, since intranasal administration of SWAP alone induced a Th1 type response in the spleen and in the lungs.
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5. |
- Akhiani, Aliasghar, 1957, et al.
(author)
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Lack of interferon-gamma receptor does not influence the outcome of infection in murine schistosomiasis mansoni
- 1996
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In: Scand J Immunol. ; 43:3, s. 257-62
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Journal article (peer-reviewed)abstract
- Studies of vaccine-induced immunity in experimental schistosomiasis in mice have suggested that interferon-gamma (IFN-gamma) is an important factor for the induction of protective immunity against schistosomiasis. The present study compares some parameters during primary schistosome infection in IFN-gamma receptor deficient mice and wild type mice. No significant difference in worm burden between the two groups was found. Almost the same number of eggs in the liver as well as typical granulomas with numerous macrophages and eosinophils were observed in both groups of mice. Furthermore, IFN-gamma receptor deficient mice infected with S. mansoni displayed a significant reduction in the number of IgG2a secreting cells in the spleen and a significant enhancement of IgA secreting cells in the spleen and in the lungs. These findings suggest that the lack of IFN-gamma activity may result in an enhanced dominance of Th2 cells which, however, does not influence the development of a primary schistosome infection.
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