摘要:

SUMMARYA comparative study of the cellular response toSchistosoma japonicumeggs was conducted in order to explore its significance, using hosts with differing susceptibilities to the parasite. In experimentally induced, synchronized hepatic granuloma formation, animal species formed each characteristic feature of the granulomas, and the magnitude of tissue reaction was significantly larger in highly susceptible hosts, such as mice and hamsters, while less susceptible hosts, such as rats and quails, formed smaller granulomas. Confluent neutrophils were seen within the tissue lesions for mice and hamsters, while rats and quails showed obviously scanty neutrophils. Guinea pigs failed to develop any granulomas. When splenic cells and bone marrow cells were used forin vitrogranuloma formation, bone marrow cells showed markedly higher reactions than splenic cells from naive or sensitized animals and the reactivities of bone marrow cells from susceptible hosts, mice and hamsters, were clearly higher than those from rats, indicating similar results to those ofin vivogranuloma formation. This study indicates that thein vivoandin vitrocellular response toS. japonicumeggs varies greatly according to the host's susceptibility, independent of whether the host is a naive or sensitized animal. Our results seem to support the concept that the parasites exploit the host immune system in order to complete their life‐spa

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1996.tb01026.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

SUMMARYThe cross‐reactive idiotype (Hu‐SJ‐CRIM) is defined by polyclonal human anti‐idiotypic antibodies derived from chronically S. japonicum infected patients. The present study shows that serum levels of Hu‐SJ‐CRIMexpressed by antibodies to S. japonicum soluble egg antigen (SEA) are associated with acute infection and hepatosplenic disease. Xenogeneic anti‐idiotypic antisera (anti‐Hu‐SJ‐CRIM) suppressed human lymphocyte blastogenesis to SEA in vitro by 47–82% (P<005). These anti‐idiotypic antibodies also suppressed in vitro granuloma formation induced by SEA coated beads in a dose dependent manner. This immunosuppression was antigen specific in that mitogen (PHA) or non‐related antigen (PPD) induced blastogenic responses were not suppressed. Surprisingly, anti‐idiotypic antibodies (anti‐SJ‐CRIM), which describe the mouse correlate CRIMwere not suppressive in the human blastogenesis or in vitro granuloma formation assays. These data indicate a dichotomy in the function and specificity of the idiotype/anti‐idiotype human and murine immune networks in S. japonicum infection. Thus, only the patient derived molecules and serology form the basis for an immunoregulatory ne

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1996.tb01027.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

SUMMARYThe role of MHC class II in the presentation ofHeligmosomoides polygyrusantigens has been investigated, using a number of T cell hybridomas produced in A and E positive and negative mice. By using fixed and irradiated antigen presenting cells (APC), further evidence has emerged, to support earlier data, that there can be differential processing requirements during the presentation ofH. polygyrusantigens by A and E molecules. In concordance with these earlier observations, this work provides further evidence that individual T cells can respond to antigen when presented by more than one MHC molecule. Previously, this evidence has been restricted to individual MHC molecules of the same haplotype, hut these data show thatH. polygyrusproduces antigens which can he presented by both syngeneic and allogeneic MHC molecules. These antigens do not appear to be synonymous with the previously describedH. polygyrussuperantigen, as presentation is restricted to specific MHC haplotypes. It is proposed thatH. polygyrusmay produce these antigenic molecules as part of its strategy to manipulate the host immune system.

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1996.tb01028.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

SUMMARYEchinococcus granulosusis the causative agent of hydatid disease in humans and animals. Natural transmission of the parasite occurs between dogs as definitive hosts and animal intermediate hosts. There is an urgent need for improved methods to control the parasite's transmission. Here we describe the development of a vaccine based on a cloned recombinant antigen from the parasite egg (oncosphere). Sheep vaccinated with the antigen, designated EG95, are protected (mean 96–98%) against hydatidosis developing from an experimental challenge infection withE. granulosuseggs. The vaccine will provide a valuable new tool to aid in control of transmission of this important human pathogen. It also has the potential to prevent hydatid disease directly through vaccination of human

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1996.tb01029.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

SUMMARYSpecific and non‐specific parasite‐induced changes in lymphocyte responses were analysed in C57BL/6J mice after intrahepatic infection with Echinococcus multilocularis. Spleen cells harvested at selected times after infection were in vitro stimulated with mitogens or a crude soluble parasitic extract (EmAg) at an optimized dose. Cell proliferative responses to Con‐A were not modified by the infection over the first 22 weeks. In contrast, LPS‐induced responses were decreased from the 13th week. A strong CD4+proliferative T‐cell response to the parasitic extract of infected mouse spleen cells was observed at the early stage of infection. This response then progressively decreased but remained significantly higher than that of control mice until the 19th week of infection. Cytokine production was investigated after in vitro EmAg stimulation of spleen cells. IFN‐γ, IL‐2. IL‐5 were produced within the first weeks after infection whereas the detection of IL‐10 was slightly delayed. Thus, the promotion of the disease does not appear associated with the expansion of one rather than another T‐cell subset in C57BL/6J mice. A general immunosuppression affecting both mitogenic and parasite‐specific T‐cell responses was observed at

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1996.tb01030.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

SUMMARYGlutathione‐s‐transferase activity was determined in filarial parasites. The activity was detected in adult stages of cattle parasiteSetaria digitata.It was absent in other stages of Setaria and also in infective larval stages ofWuchereria bancroftiandBrugia malayi.The activity was enhanced about twenty five fold following purification of adult setaria extracts on glutathione agarose column. Antibody (IgG and IgM) levels to the affinity purified proteins (SdGBP) were detected predominantly (90%) inWuchereria bancroftiinfected individuals compared with normal residents of endemic regions. IgA and IgE responses could not be detected. Filarial sera in contrast to non‐filarial caused reduction in the enzymatic activities of Sd GBP. Micro‐filaraemic sera after dielhylcarhamazine treatment resulted in enhanced reduction of enzymatic a

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1996.tb01031.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

SUMMARYDiethylcarbamazine (DEC) induced clearance of microfilaraemia in loiasis is associated with severe posttreatment reactions. To define the switch from hypo‐ to hyper‐responsiveness associated with DEC treatment, phenotypic alterations of T‐lymphocytes, characterized by flow cytometry, and cytokines, determined by enzyme linked immunosorbent assay, were monitored in a microfilaraemic patient. In contrast to reports on onchocerciasis and lymphatic filariases, no elevation of interleukin (IL)‐6 and tumour necrosis factor (TNF)‐α was observed. The most severe side effects coincided with an elevation of interferon (IFN)‐γ on day 3, followed by IL‐10, transforming growth factor (TGF)‐β2 and macrophage inflammatory protein‐1α (MIP‐1α) peaking on day 5. Phenotypieally, T‐cell activation markers CD38, CD54 and CD25 were significantly expressed before treatment, with high CD38 expression still existing one year after clearance of microfilaraemia. Treatment‐related increases were observed with anti‐CD 122, anti‐HLA‐DR and anti‐CD69. CD28 was expressed before treatment on almost 100% qf'CD4+and CD8+T cells and dropped to 20% by day 5, reaching again baseline levels on day 21. Furthermore, there emerged 20% TCRαβ‐/CD3+T cells and 10%) anti‐βV5(e)+T cells, altogether indicating a specific pattern of T‐helper (Th)1 and Th2 cytokines as well as expansion of certain pauciclonal T‐cell pop

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1996.tb01032.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY