摘要:

SummaryIn the present paper, we have characterized the specificity of a series of monoclonal antibodies (MoAbs) against Plasmodium berghei sporozoites, selected for their lack of reactivity with the repeat domain of the circumsporozoite (CS) protein. We found that these MoAbs recognize Pb44, the mature membrane form of the CS protein, but they do not react with Pb54, its precursor. Furthermore, these MoAbs do not react with any of the synthetic peptides representing the linear sequence of the P. berghei CS protein nor do they react with a recombinant CS (rCS) protein. These observations indicate that the epitope recognized by these antibodies is expressed only after the processing of the CS protein has occurred. This ‘processing dependent epitope’ is present in sporozoites of P. berghei, and also in those of P.falciparum, P. yoelii and P. brasilianum. It is not present in sporozoites of the P. cynomolgi‐P. vivax complex and of P. gallinaceum. These anti‐sporozoite MoAbs strongly inhibit sporozoite invasion of hepatoma cells, in vitro, however, they displayed no protective effect in an in viv

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1992.tb00020.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

SummaryThe Plasmodium falciparum zygote ookinete surface protein, Pfs25, persists in the oocyst wall throughout its development. Anti‐25 kD transmission blocking antibody, given to infectedAnopheles stephensiorA. gambiaemosquitoes in an additional bloodmeal, 3–6 days after being fed gametocyte infected blood, penetrated the oocyst and reacted with the 25 kD protein within it. This reaction caused a significant reduction in the number of developing sporozoites. Mouse serum containing antibodies raised by immunization with a recombinant 25 kD yeast product showed a similar eff

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1992.tb00021.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

SummaryAn immunocytochemical peroxidase test (ICPT) has been developed to allow serological measurement of the antibody response to Plasmodium vivax by light microscopy. Acetone fixedP. vivaxerythrocyte stages were used as source of antigen. The immunofluorescent antibody test (IFAT) was used as reference test. In testing sera from individuals infected withP. vivaxin southeastern Venezuela a high correlation (100%) was obtained between the ICPT and the IFAT. There were cross reactions with sera from patients with malaria byP. falciparumbut not with those from patients with other parasitic diseases. Antibody titres as measured by the ICPT showed a positive correclation with pastP. vivaxmalarial experiences.

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1992.tb00022.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

SummaryA study is described in which the role of carbohydrate epitopes in the generation of protective immunity toTrichinella spiraliswas investigated. Antigen preparations were treated with increasing molar concentrations of sodium periodate, which is known to degrade carbohydrate moieties by cleaving one side of the hexose ring, and a suitable protocol was established for the selective degradation of carbohydrates with the retention of protein integrity. Using excretory/secretory (ES) proteins, both sodium periodate treated and in their native form, vaccination experiments have shown that sodium periodate treated antigens are as effective as native ES proteins in the generation of both active and passive immunity. This indicates that peptide epitopes alone can induce protective immunity toT. spiralis.

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1992.tb00023.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

SummaryHypodense eosinophils are observed in peripheral blood and tissue from patients with eosinophilia due to helminthic infections. In this study, the variation in eosinophil density was examined in rats duringTrichinella spiralisinfection. Hypodense eosinophils were observed in the peripheral blood in association withTrichinellainfection. In peritoneal fluid, which was representative of tissue fluid, a majority of eosinophils were hypodense regardless of the infection. During the course of tissue eosinophilia after the infection, there was a particular increase in the lowest dense cells in the population of hypodense eosinophils. Eosinophils with lower density, demonstrated larger diameters and had more potent cytotoxic activity.

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1992.tb00024.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

SummaryUV‐irradiated and gamma‐irradiated schistosomula ofSchistosoma mansoniinduce high levels of resistance to challenge infection in experimental hosts. It was observed that both types of irradiation severely inhibited protein synthesis by the parasite larvae. Schistosomula were treated with the metabolic inhibitor actinomycin D to simulate this effect of irradiation. The ability of these drug‐treated larvae to induce immunity was tested in animal protection experiments. Our results suggest that inhibition of protein synthesis may help to generate the enhanced immunogenicity of irradiated schistosomula. In explanation, we propose that irradiated schistosomula may be such potent immunogens because they express antigens in disrupted, abnormal conformations. Inhibition of protein synthesis may both directly create such modified antigens, and also ensure that they persist and accumulate for presentation to the host immune s

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1992.tb00025.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

SummaryAn ELISA and a lymphocyte proliferation assay were used for the detection of anti‐Leishmaniaantibodies and parasite specific cellular immunity respectively in a preliminary study of canine leishmaniasis in Oporto, Portugal. A high rate of infection was found considering the comparatively small group sampled. Of 34 dogs examined two had anti‐leishmanial antibodies but their lymphocytes did not proliferate in the presence ofLeishmania infantum. Conversely two dogs demonstrated antigen specific lymphocyte proliferation in the absence of any detectable anti‐parasite antibodies. To our knowledge this is the first time that cellular immunity and presumably resistance of dogs to leishmanial infection has been demonstrated. These results suggest that there may be a spectrum of canine leishmaniasis similar to that observed in the human di

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1992.tb00026.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

SummaryAntibody‐mediated mechanisms that could be important in controlling microfilaraemia inLoa loainfected amicrofilaraemic adults (mf‐ve) were studied. These subjects were selected as having a verified ocular passage of an adultL. loabut being amicrofilaraemic and without recent diethylcarbamazine treatment. Sera from 37 mf‐ve subjects were compared to 14 sera from heavily (>4000 mf/ml) infected subjects (mf+ve) and 9 sera from Caucasian control subjects for their reactions withL. loamf (mf). Many mf‐ve sera (22/37) were strongly positive in immunofluorescence (IFAT) on living mf. Mf+ve sera were negative, or only weakly positive, and Caucasian sera were negative. Clinical signs were not significantly different between IFAT reactive and non‐reactive mf‐ve subjects. Approximately half of the IFAT positive, mf‐ve sera were also able to agglutinate mf: no other sera were active in this test. Titres ranged from log2 3–6 and in most cases, 9/11, the agglutination reaction was mercaptoethanol‐sensitive. Antibody‐dependent cellular adherence was studied using mf and leukocytes from uninfected donors. Using cryopreserved mf many heat‐inactivated mf‐ve sera gave strong reactions with obvious adherence by 4 h and few motile mf remained by 16 h but when fresh mf were employed these reactions were weak. However, addition of complement to many (10/11) mf‐ve sera considerably enhanced adherence to fresh mf. The effect of various treatments on the complement source indicated a role for both the classical and alternative pathways. The cells attached to mf were mainly neutrophils (83%) with some eosinophils (15%) and few mononuclear cells (2%). The common occurrence of antibodies able to mediate complement‐dependent adherence of polymorphonuc‐lear leukocytes toL. loamf in the sera of mf‐ve subjects may indicate that such a mechanism is important in con

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1992.tb00027.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

SummaryMice were immunized with one of twoSchistosoma mansoniantigens, Sm20 and Sm50, expressed as fusion proteins withSchistosoma japonicum26 000 Dalton glutathione‐S‐transferase (GST) or with GST alone. Antibody responses to GST were shown to be critically dependent on the adjuvant used. In Sm20‐GST immunized mice, we noted a striking bias to respond either to Sm20 or to GST according to the adjuvant used and responses to both in the same individual were rare. Fusion with Sm50, which is relatively non‐immunogenic, appeared to down‐regulate respons

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1992.tb00028.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY