摘要:

SummaryPeritoneal exudate cells (PEC) from normal jirds (Meriones unguiculatus) showed adherence toBrugia pahangimicrofilariae, and subsequent cytotoxicity in the presence of antimicrofilarial antisera. Heat inactiviation of the antisera diminished both adherence and cytotoxicity, but readdition of fresh normal jird sera only partially restored the reactions. Macrophages were the predominant adherent cell type. Circulating immune complexes precipitated with polyethylene glycol (PEG) from the sera of jirds with an 8‐month infection inhibited both of these reactions. Complement consumption by the precipitated complexes was found not to be the cause of inhibition. Blocking of adherence and cytotoxicity by circulating immune complexes may be preventing the trapping of microfilariaein vivo, and may play a role in the persistence of microfilaraemia in the jir

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1982.tb00415.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

SummaryImmunodepression phenomena in infections with protozoan and metazoan parasites have raised a great deal of interest because of the apparent lack of immunological control in a primary infection. Therefore, this phenomenon has been proposed as a working hypothesis to explain the successful association. However, the role that immunodepression can play in parasitic infections as a mechanism to assure an equilibrium between the host and its parasite has never been evaluated. The immunodepression to SRBC in Trichinella‐infected mice was removed by treating mice with low doses of cyclophosphamide (CY). The elimination of immunodepression resulted in a significantly lower number of encysted muscle larvae. In the absence of immunodepression, a higher number of circulating eosinophils was counted. The results of these experiments are discussed firstly with regard to the mechanisms which could explain immunodepression in trichinellosis and secondly, the role that immunodepression plays in the relationship between the host and the parasite during a primary infectio

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1982.tb00416.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

SummaryFerritin‐labelling techniques at the ultrastructural level have shown that antiserum from August rats immune toP. bergheiinfection contains antibodies which bind to the surfaces of parasitized reticulocytes but not to uninfected cells. Two antibody specificities have been demonstrated by comparing antisera i absorbed with infected reticulocytes, ii absorbed with uninfected reticulocytes, and iii unabsorbed. Ferritin labelling was much increased with antiserum preabsorbed with uninfected reticulocytes, and also with heat‐inactivated serum, indicating a blocking effect on parasite‐specific antibody binding by cold‐reacting anti‐erythrocyte isoantibodies known to be present. Energy‐dependent aggregation, shedding and endocytosis of labelled material was observed at the surfaces of unfixed infected re

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1982.tb00417.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

SummaryCulture of murine lymph node cells together with living protoscolices ofEchinoccus granulosusis described. The presence of the parasite induced potent blastic transformation in lymphocytes of unimmunized mice as indicated by tritiated thymidine incorporation. The response was markedly reduced by killing the parasite immediately prior to culture. No blastogenic activity was detectable in supernatants from living parasites cultured alone. Protoscolices from artificially infected syngeneic mice were effective stimuli, as were protoscolices from naturally infected horse and sheep. Stimulation was not detectably reduced by maintenance of the parasitein vitrofor 72 h at 37°C or for 46 days at 4°C prior to culture. It is concluded that unprimed lymphocytes are stimulated to transform by surface contact with a stimulator synthesized, but not secreted, by the parasite. The biological significance of the reaction and its possible contribution to immunosuppression are discusse

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1982.tb00418.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

SummaryHumoral and cellular immune responses have been evaluated in two inbred strains of mice which differ markedly in their susceptibility to infection withGiardia muris.Serum IgG and IgA antibody levels and IgA levels in intestinal washes were determined by a solid‐phase radioimmunoassay usingG. murisantigen prepared by sonication of trophozoites, while cell‐mediated immunity was assessed by a radiometric ear‐assay for delayed‐type hypersensitivity. Following infection of BALB/c mice (resistant) and C3H/He mice (susceptible), the IgG and IgA antibody levels in serum progressively increased over the period of study with C3H/He mice having significantly higher titres of IgA antibodies than BALB/c late in the infection. Systemic immunization withG. muristrophozoites resulted in high titres of IgG antibodies in the serum. IgA antibodies were detected in intestinal washes 2 weeks after infection with a subsequent fall in levels in BALB/c mice but a progressive increase in levels in C3H/He mice. Prior immunization resulted in IgA antibodies being detected earlier in the intestinal washings after a challenge infection. Delayed‐type hypersensitivity toG. murisantigens could not be detected during an infection but a positive response was elicited following antigen priming in mice pretreated with cyclophosphamide. The immune responses evaluated in this study were assessed using a wholeG. muristrophozoite sonicate and variations in the quantitative aspects of the responses did not account for observed differences in the course of infection in the two strain

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1982.tb00419.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

SummaryAnti‐thymocyte‐serum (ATS) treated Wistar rats infected with 100 cysticercoids of the rat intestinal cestodeHymenolepis diminutashowed a delayed destrobilation and expulsion of the worms compared with saline‐treated infected rats. This result strengthens previous evidence of an immunological nature of the destrobilation and expulsion in lumen‐dwelling cestodes—even in their most susceptible hosts. The migration of the worms in the small intestine during the first 20 days of a primary 100‐worm infection is described and the anterior migration of the destrobilated worms to the first 10% of the pylorus is emphasized and compared with similar migrations of the nematodeNippostrongylus brasiliensisin the rat. No serum antibodies were detected using passive cutaneous anaphylaxis and the indirect immunofluorescence test, although the thymus‐independent areas of the mesenteric lymph nodes showed an increase in pyroninophilic cells. In the small intestine, no response to the tapeworm infection could be detected in pyroninophilic cells and globule leucocytes, but mast cell and eosinophilic cell numbers were increased in the saline‐treated infected rats. Although the host responses toH. diminutaare shown to be thymus‐dependent, the possibility of thymus‐independent activity in the host reactions

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1982.tb00420.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY