摘要:

SummaryThe course of primary infections withNippastrongylus brasiliensiswas followed in nude (CBH/R nu/nu) and heterozygote(CBH/R nu/+) rats. In both nude and heterozygote rats peak egg production byN. brasiliensisoccurred on days 7 and 8 post‐infection. However, whereas in heterozygote rats egg production declined rapidly thereafter and ceased completely by day 14 post‐infection, in nude rats high numbers ofN. brasiliensiseggs were still seen on day 27 post‐infection, when the experiment was terminated, in comparison with the nude rats, heterozygote rats had a 5‐fold greater loss of weight by day 9 post‐infection and a 4‐fold higher incidence of diarrhoea. Furthermore, infected heterozygote rats became anaemic whereas uninfected rats and infected nude rats showed no evidence of anaemia. Free radical generation was measured in infected (9 days) and uninfected rats. Leucocytes from infected heterozygote rats were able to generate copious quantities of free radicals in response toN. brasiliensiswhereas leucocytes from infected nude rats produced only slightly more free radicals than uninfected rats. Thus, worm rejection, weight loss, diarrhoea, anaemia and free radical generation in response toN. brasiliensisinfection arc all T‐cell dep

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1991.tb00553.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

SummaryMonospecitic rabbit an user a obtained through experimental immunization with previously purified proteins were used in the structural localization of two hydatid fluid antigens, antigen 5 and antigen B, in cyst membranes and protoscoleces ofE. granulosusfrom human origin. The antigen‐antibody reaction was revealed by an avidin‐biotin‐peroxidase technique. Antigen 5 was not evident in the laminated membrane of the cyst wall, but it was associated with the germinal membrane of the cyst wall and brood capsules. The parenchyma of invaginated and evaginated protoscoleces was heavily labelled. The tegument, the calcareous corpuscles, the suckers and the hooks did not contain antigen 5. Degenerated protoscoleces were also labelled. Antigen B localization was essentially identical to antigen 5. but degenerated protoscoleces were not recognized by anti‐antigen B anliserum. Technical aspects and differences with previously published work arc di

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1991.tb00554.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

SummaryThe 20 kDa calcium binding protein ofSchistosoma mansoni, Sm20. is expressed in all stages of the life cycle from the cercaria to the adult worm and in the egg, with equal levels of Sm20 present in adult male and female worms. Localization of Sm20 by immuno‐electron microscopy using Sm20‐specjric antisera and the protein A gold technique demonstrated that the majority of Sm20 is expressed in muscle but that it may also be expressed at low levels in the tegument. These results suggest that Sm20 plays a role in the calcium mediated regulation of muscle contraction. However, it is not clear whether Sm20 acts as a reservoir for calcium in muscle or is directly involved in the regulatory mechanisms of contract

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1991.tb00555.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

SummaryCattle infested with the tickBoophitus microplusproduce antibodies lo intrinsic membrane glycoproteins of the lick, as well as to Bm86. a well characterized antigen from the tick gut. Several factors explain how cattle could produce antibody to such antigens, which one would expect to be ‐concealed from the host's immune system, during natural infestation. Il has been shown that the carbohydrate determinants on many tick glycoproteins are cross‐reactive immunologically and that the reaction of bovine antibodies with intrinsic membrane glycoprotein is at least partially blocked by low molecular weight carbohydrate. Further, antisera from cattle exposed to licks read with a glycosylated, native Bm86 but not with a non‐glycosylated, recombinant Bm86. Thus the reaction of concealed antigens with antibodies produced as a result of lick infestation appears to be due lo a relatively non‐specific reaction with carbohydrate determinants on tick glycoprotein. Evidence is also presented that antibodies directed against carbohydrate determinants of Bm86 arc not protective. Care must therefore be exercised in interpreting the results of antibody reaction with glycoproteins in such complex or

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1991.tb00556.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

SummaryParasitological and immune‐logical responses of genetically resistant and random‐bred lambs to primary and secondary infection withH. contartus were studied. Resistant lambs had higher faecal egg counts and total worm burdens than the random‐bred lambs Following the primary infection. As there were no significant differences in serum and antibody levels, mucosal mast cells, circulating and tissue eosinophils between the two groups, it is inferred that what ever the underlying mechanism it was an innate characteristic. In contrast to primary infection, resistant lambs had significantly lower faecal egg counts and worm burdens than the random‐bred lambs on secondary infection. Resistant lambs also exhibited significantly higher antibody levels, mucosal mast cell hyperplasia and mucosal eosinophilia in response to a challenge infection than the random‐bred lambs. Furthermore, levels of mast cell hyperplasia and anti‐Haemonchusantibodies correlated positively with the resistance status of the host. Taken together these results suggest that the genetic resistance of sheep toH. contoriusresults from the expression of an acquired immune response, and that anti‐parasite antibodies and mast cell‐derived mediators may play an important role in genetically determined resistance of sheep

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1991.tb00557.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

SummaryThis study examines the age‐dependency of the relationships between human infection with whipworm (Trichuris trichiura) and parasite‐specific antibody level measured by ELISA against an extract of adult worms after preincubation of the sera withAscaris lumbricoidesadult worm extract. The convex age‐profile of parasite infection intensity is shown to be mirrored ban ase‐dependent change in age‐class mean levels of IgG (all subclasses except IgG3). IgA. IgM and IgE. Mean antibody levels rise with increasing acquisition of infection in childhood and decline as the intensity of infection falls in adulthood. Immunobiot analysis of selected sera from different age‐classes indicates that antigen recognition is simitath dependent on infection intensity. In individual children, antibody levels correlate positively with acquisition of infection, consistent with a simple model of antigen dosage specifying the magnitude of the humoral immune response. In adults, Igd correlates positively and IgA negatively with intensity of infection, suggesting involvement of these isolypes in functional roles of immune blockade or effector mechanisms, r

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1991.tb00558.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

SummaryThe degree of resistance to a localLeishmania amazonensischallenge has been compared in lines of mice obtained by selective breeding for high or low immunoresponsheness: High and Low antibody responder mice of Selections I and II (H1, H11and L1L11lines) and high and low responder mice to T mitogen PHA (Hi/PHA and Lo/PHA). The aim of this preliminary study was to focus attention on genetic differences related with well defined immune characteristics. Clear‐cut results were obtained, both H1and H11mice developed large and disseminating lesions, the rale of symptom aggravation being faster in H11, while L1and LM proved resistant to parasites, only small and transient lesions being observed for them during a 150 days follow up. The outcome of infection also differs in Hi/PHA and Lo/PHA mice, Hi/PHA having a resistant and Lo/PHA a susceptible phenotyp

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1991.tb00559.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

SummaryAthymic nude mice of the outbred Zur:ICR‐nu and inbred BALB/c strain and scid mice were infected with a cloned human isolate ofGiardia lamblia(GS M‐83‐H7). Changes in the expression of the major surface epilope of the intestinal trophozoites (characterized by the binding capacity of monoclonal antibody MoAbG 10/4) as well as cellular and humoral immune parameters of the hosts were followed during the course of infection. Self‐cure was observed in hetcrozygous (nu/+) BALB/c mice by day 22 post‐infection (p.i.) and in heterozygous (nu/+) Zur:ICR‐nu strain by day 65 p.i. Homozygous (nu/nu) mice of both strains remained chronically infected until end of the experiments (day 45 p.i. for BALB/c mice and day 122 p.i. for Zur:ICR‐nu mice, respectively). Only heterozygous (nu/+) mice were able to mount a gut‐associated (Peyer's patch) lymphoproliferative response toG. lambliaantigen. Therefore, T‐cell dependent mechanisms were necessary for a self‐cure. Antigenic variation occurred in all nu/+ and nu/nu animals of both strains. Trophozoiles expressing the major surface epitope (assessed by direct immunofluorescence with FITC‐labelled MoAb G10/ 4) decreased to zero by day 22 p.i. In contrast, the proportion of trophozoites expressing the major surface epitope in infectedscidmice remained at the initial level (>99%) until termination of the experiment (day 25 p.i.); therefore, antigenie variation did not occur. All nu/nu and nu/+ mice but notscidmice demonstrated a humoral immune response toG. lambliaantigen. These experiments suggest functional B‐cell dependent mechanisms are most likely responsible for the surface antigen switch. Transfer of infection occurred naturally from experimentally infectedscid‐mice to their mother, proving the initial antigenic surface variant remains unchanged after encystment and subsequent excystmenl followed b

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1991.tb00560.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

SummaryTreatment of membrane antigens of the midgut (GM) of the cattle tick,Boophilus micropluswith sodium metaperiodate (periodate). pronase and lipase significantly inhibited the reactivity of the GM with antibodies in the sera of 57 cattle vaccinated with GM. Treatment of GM with periodate only removed the correlation between antibody reactivity of sera and protection against infestation with licks. A monoclonal antibody (MoAb QU13). which recognises protective antigens solubilized from GM (Lee&Opdebeeck 1991), did not react with GM treated with penodate. Cattle vaccinated with GM extracts were significantly protected against infestation with cattle licks (P<005), whereas cattle vaccinated with either GM extracts treated with periodate or with antigens precipitated from GM extracts with MoAb QU13 and also treated with periodate, were not protected against infestation. These studies provide preliminary evidence that protective antigens in the lick midgut membrane either are carbohydrate or arc dependent on carbohydrate for their specificity.

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1991.tb00561.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

SummaryIn order to evaluate the relationship between fever and macrophage activation in vivax malaria, serum inierferon‐gamma (IFN‐y) and urinary neopterin concentrations were determined in That adults withPlasmodlum vivaxparasitaemia. Magnitude of fever, after controlling for parasite density, was found to be positively correlated with both IFN‐y(r = 0‐47) and neopterin (r = 0‐57). In the 26 febrile patients, neopterin excretion increased further during the first two days of chemotherapy (P=0‐0002). Mean neopterin values for both groups had fallen to within the normal range by the sixth day post‐trealmem. Thus, the fever of vivax malaria was associated with IFN‐y induced macrophage activation, as reflected by neop

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1991.tb00562.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY