摘要:

We have made a comparative analysis of human cellular and antibody responses to membrane associated adult worm antigens (Mb‐A), soluble adult worm antigens (SWAP) and soluble egg antigens (SEA) derived fromSchistosoma mansoni. Chronically infected patients with the intestinal (I) and hepatosplenic (HS) forms of the disease as well as non‐infected putative immune ‘endemic normals’ (EN), were studied. We observed that the cellular responses, of individuals, to the two adult worm preparations, SWAP and Mb‐A, may be distinct and can be related to the occurrence of resistance or pathology. The resistant group (EN) presented higher levels of both cellular proliferation, and IFN‐γ production, in response to Mb‐A as compared with SWAP whereas HS individuals presented higher levels of cellular proliferation to SWAP as compared with Mb‐A. Individuals with intestinal disease had similar levels of proliferation to both antigens. The response to SEA by all groups was generally similar, and not predictive of any clinical form. The specific antibody response to the three antigens were in general higher among infected patients than in resistant EN individuals. These results support the hypothesis that the response to adult worm antigens may be pivotal in determining both the development of resistance and sev

ISSN:0141-9838    

DOI:10.1046/j.1365-3024.1996.d01-49.x

出版商:Blackwell Science Ltd    

年代:1996

数据来源: WILEY

摘要:

Immunomodulation of macrophage activity by in vitro secretions ofMesocestoides cortihas been previously demonstrated. The modifying activity secreted byM. cortihad the effect of reducing the normal accessory function of macrophages in a Con‐A‐activated lymphocyte proliferation assay. This paper describes the purification of the modifying activity by FPLC techniques and the generation of a monoclonal antibody (MoAb) to this molecule in mice. The MoAb bound immunomodulatory FPLC fractions ofM. cortiin an ELISA. When MoAb was applied in conjunction with immunomodulatory parasite secretions to macrophagesin vivoorin vitro, the modifying effect of the secretions was abolished. This profound effect of the MoAb should help to elucidate the mechanisms by which metacestode parasites avoid host immune responses and may enable therapeutic intervent

ISSN:0141-9838    

DOI:10.1046/j.1365-3024.1996.d01-48.x

出版商:Blackwell Science Ltd    

年代:1996

数据来源: WILEY

摘要:

The efficacy of cyclosporin A (CsA) treatment againstSchistosoma mansoniin mice was compared with treatments that included co‐administration of one of two anti‐sera (infected rabbit serum (IRS) obtained by repeated infection and a worm membrane antigen anti‐serum (WSS) obtained by immunization with worm surface supernatants). These two sera recognized a number of worm antigens but differed in precise detail. Administration of CsA alone to mice harbouring mature infections ofS. mansonireduced worm burdens and preferentially targeted female worms. Sera administered alone had no effect on worm burdens. Co‐administration of worm membrane antigen anti‐serum (WSS) with CsA reduced worm burden significantly compared with drug treatment alone. Male worms were more susceptible to this combined treatment regime. Anti‐infection serum (IRS) had a lesser stimulatory activity in combination with CsA which was not statistically different from the effects of CsA alone on worm burdens. The data suggest that CsA‐induced surface damage to the parasite may reveal specific antigens that were previously unavailable fo

ISSN:0141-9838    

DOI:10.1046/j.1365-3024.1996.d01-53.x

出版商:Blackwell Science Ltd    

年代:1996

数据来源: WILEY

摘要:

Serum from cats(Felis catus)that were repeatedly infected withBrugia pahangiand had become amicrofilaraemic (mf‐ve) was injected intravenously into microfilaraemic (mf + ve) cats. If more than 1 μl of immune serum per 1000 mf was injected, microfilarial counts fell dramatically within minutes and, in some cats, mf completely disappeared. In most cases mf reappeared 21–44 days later. However, in two experiments mf never reappeared and circulating antigen (indicative of the presence of living adults) could not be detected. At autopsy no adult worms were found, but in one cat 6 mf/ml were detected by filtration of cardiac blood. Passive transfer of single Ig isotypes showed that IgG is the immunoglobulin responsible for the mf killing effect of immune serum, and that IgGl is probably the most active isotype. Mf killing and destruction, occurred in the lungs in an antibody dependent cell mediated reaction involving neutrophils, eosinophils and mononuclear cells. Three of the 20 recipient cats died from what appeared to be anaphylactic shock while under anaesthesia probably due to the sudden release of inflammatory mediato

ISSN:0141-9838    

DOI:10.1046/j.1365-3024.1996.d01-50.x

出版商:Blackwell Science Ltd    

年代:1996

数据来源: WILEY

摘要:

The production of high levels of IgG1, by mice chronically infected with the parasitic nematodeHeligmosomoides polygyrus, has been documented for a number of years. In order to investigate this phenomenon, naive lymphocytes from B10.D2 mice were incubatedin vitrowithH. polygyrusadult worm homogenate (AWH) and the culture supernatants examined for immunoglobulin production. Stimulation of pooled naive splenocytes by AWH was found to produce IgG1, but not IgM, in an antigen dose dependent manner. Identical stimulation of splenocytes of individual inbred mice, indicated that this effect was reproducible but with considerable variation between mice. When the IgG1 produced was tested for specificity, it was found that there was little evidence that the immunoglobulin produced was able to bind to the inducing parasite antigens. Analysis of purified T cells reconstituted with splenocytes, demonstrated that T cells were the target lymphocytes of the stimulating molecule, contained within AWH. These results show thatH. polygyrusAWH can induce the production of non‐parasite specific IgG1 from naive splenocytes and that this production is crucially dependent upon the cell content of thein vitroculture. Furthermore, the production of IgG1 is not proportional to the degree of lymphocyte proliferation. It is suggested that at least part of the hypergammaglobulinaemia produced during a primaryH. polygyrusinfection, is due to this non‐specific stimulation of mouse lymphocytes by the paras

ISSN:0141-9838    

DOI:10.1046/j.1365-3024.1996.d01-52.x

出版商:Blackwell Science Ltd    

年代:1996

数据来源: WILEY

摘要:

Immunization of mice with irradiatedOnchocerca volvulusinfective stage larvae (L3) has been demonstrated to confer protection against challenge infections with these larvae. Additionally, cytokine level measurements and cytokine depletion studies have shown that both IL‐4 and IL‐5 are important in generating a protective immune response againstO. volvuluschallenge infections, thus suggesting a dependency of protective immunity on IgG1, IgE and/or eosinophils. In the present study, we examined the humoral responses of immunized mice toO. volvulusL3 antigens. ELISA measurements of total serum antibody levels indicated that IgE was the only antibody isotype elevated in mice immunized withO. volvulusL3. IgM from immunized mice was the only isotype that recognized surface antigens on intactO. volvulusL3. IgG1, IgG3, IgE and IgA recognized internal parasite antigens onO. volvulusL3 frozen sections. Western blot analysis of L3 proteins showed that in serum from mice immunized withO. volvulusL3 IgG1, IgG2a/2b, IgA, and IgE, as well as IgM, recognized unique L3 proteins. Antibodies in serum from L3 immunized mice were able to detectO. volvulusadult antigens in a pattern similar to the recognition found inO. volvulusL3. Some L3 antigens were shared by adults, while other antigens were L3 specific. The ELISA, immunohistochemistry and Western blot findings thus demonstrate a complex pattern of antigen recognition of parasite antigens by antibodies found in mice immune to the L3 ofO. vo

ISSN:0141-9838    

DOI:10.1046/j.1365-3024.1996.d01-51.x

出版商:Blackwell Science Ltd    

年代:1996

数据来源: WILEY

摘要:

Pfs48/45, a sexual stage parasite protein doublet ofP. falciparum, is a target of antibodies which inhibit the development of the parasite in the mosquito. Twenty‐eight (54%) out of 52 sera of gametocyte carriers from Cameroon reduced infectivity in the mosquito membrane feeding bioassay to less than 20% of the controls. These 52 sera were analysed by competition ELISAs for the presence of antibodies capable of competing the binding of six monoclonal antibodies (MoAbs) directed against five different epitopes on Pfs48/45. The percentage of these 52 Cameroon sera that competed with one of the MoAbs ranged from 13% (epitope I) to 33% (epitope IIc). Comparison of activity in the transmission‐blocking assay ( ≥80%) and in the Pfs48/45 competition ELISA show a relative specificity of 100% (24 of 24) and a relative sensitivity of 75% (21 of 28). Non‐blocking sera showed no competition with any of the MoAbs. These MoAbs were further used to study the diversity of epitopes among isolates ofP. falciparumusing a two‐site ELISA. MoAbs against epitope I, III and V reacted with four different isolates whereas epitope II could be subdivided into three epitopes. None of the isolates reacted with MoAb 3G12 (epitope IV). Using these four different isolates, the competition ELISA titre varies from 1/20 to 1/80 and no significant differences are found between the isolates except for epitope II where only three out of 11 positives for epitope IIa were also positive for

ISSN:0141-9838    

DOI:10.1046/j.1365-3024.1996.d01-54.x

出版商:Blackwell Science Ltd    

年代:1996

数据来源: WILEY