摘要:

SummaryIntradermal (i.d.) injection with non‐living schistosome antigens plus bacterial adjuvant protects mice against subsequent infection withSchistosoma mansoni.This protection became apparent within 2 weeks after a single inoculation and persisted for at least 8 weeks. Administration of one or more booster immunizations enhanced the level of protection but never produced complete resistance to cercarial challenge under the conditions tested. All immunized mice recognized the Sm 97 antigen in adult worms, as measured by antibody reactivity in ELISA, although the level of reactivity did not correlate with the level of resistance. Significant protection was observed when mice were immunized in the skin of the chest, the footpad or at the base of the tail if challenge infection was administered percutaneously either on the abdomen or back. However, when mice were infected by cercarial exposure of the tail skin, the level of resistance was consistently lower regardless of the immunization site. Vaccinated mice were not resistant to infection with lung stage parasites. These results demonstrate that the i.d. vaccine induces significant and persistent resistance in mice, the level of which is strengthened by booster immunization. The resistance is unrelated to inflammation at the site of immunization. However, immune response at the challenge site may play a critical role in the effector mechanism of resistance in this mode

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1987.tb00528.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

SummaryThe ability of Plasmodium chabaudi infected erythrocytes to bind to endothelial cellsin vivoand to various murine cell linesin vitrois described. A procedure for the selective recovery of a sequestering subpopulation of schizont‐infected erythrocytes from hepatic sinusoids of BALB/c mice, using a combination of body perfusion, trypsin treatment and Percoll density centrifugation was developed. The serial subinoculation of such a subpopulation was used to select for a clone of parasites (strain AJJ) with considerably better cytoadherent characteristics than the parent line (strain AJ). In contrast, it was demonstrated that another clone (PC7), showed no cytoadherencein vivoorin vitro.This study shows that parasite induced alterations occurred on the surface of erythrocytes infected with late developmental stages ofP. chabaudi.The antigenicity of these molecules in the infected mouse was demonstrated using immune serum and affinity chromatography. Cytoadherence and surface antigenic changes inP. chabaudischizont‐infected erythrocytes were demonstrated in the absence of the submembranous ‘knobs’ associated with cytoadherence inP. fal

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1987.tb00529.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

SummaryThe MHC restriction and parasite strain specificity of cytotoxic cells elicited in a group ofTheileria parva(Muguga)‐immunized cattle following homologous challenge, were investigated. The cytotoxic cells were specific for parasitized target cells and in 9 of the 10 animals examined, they were clearly genetically restricted. Cytotoxicity could be inhibited by monoclonal antibodies (MoAb) to class I MHC molecules but not by MoAb to class II molecules, indicating that a large component of the response was restricted by class I MHC determinants. Low levels of inhibition of cytotoxicity were also obtained with a MoAb to the T‐cell subset marker BoT8, suggesting that at least part of the response was mediated by BoT8+lymphocytes. When cytotoxic cells from individual cattle were assayed on panels of parasitized target cells, there was a close correlation between susceptibility of the target cells to lysis and sharing of BoLA‐A locus‐encoded specificities with the effectors. This observation, taken together with the knowledge that within several of the sets of BoLA‐A‐matched targets the relevant BoLA‐A specificities were on different MHC haplotypes, indicated that the responses were restricted predominantly by BoLA‐A products.In individual cattle there was a striking bias in the restriction of the response to one or other BoLA‐A specificity. Among the six specificities represented, responses restricted by w6, w8 and KN18 consistently predominated over responses restricted by w7, w10 and w11. In the three cattle tested for parasite strain specificity, two showed complete specificity and one partial specificity for cells infected with the parasite stock used for immunization

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1987.tb00530.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

SummaryInfection of a relatively resistant strain of mice (C57BL/6J) with the protozoan parasiteTrypanosoma cruziresults in both the induction of parasite‐specific T‐helper cells and nonspecific suppressor cells. A time course study of the activation of help and suppression revealed that parasite‐specific T‐helper cell activity increases very early in infection (<12 days) at a time when suppression of non‐parasite‐specific responses and suppressor cell activity is increasing. Between 12 and 14 days of infection, the T‐helper cell response toT. cruzi, as measured by the antibody response to hapten‐T. cruzi in vitro, is suddenly and dramatically regulated. As reported previously, plastic and G‐10 adherent cells appear to be responsible for the regulation of antibody responses to heterologous antigen duringT. cruziinfection. These adherent suppressor cells are also responsible for the suppression of antibody responses to hapten‐T. cruzifollowing the first 2 weeks of infection. Suppressor cells continue to regulate the parasite‐specific response well into chronic infection even though the response to hapten‐T. cruziappears to return to normal levels. These results are the first to directly implicate nonspecific suppressor cells in the regulation of anti‐T. cruz

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1987.tb00531.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

SummaryA T‐cell line specific for tetrathyridial antigens of the cestode parasiteMesocestoides cortiwas generatedin vitro.The T‐cells expressed the L3T4+Ly2‐phenotype and secreted the lymphokines: interleukin‐1 (IL‐1), interleukin‐2 (IL‐2), gamma interferon (IFN‐γ), colony stimulating factor (CSF), mast cell growth factor (MCGF) and eosinophil differentiation factor (EDF) in response to antigen stimulation. The line was stable for up to 16 weeks and produced an enhanced peripheral eosinophil response and a reduced parasite burden (40–50%) when adoptively transferred into naive recipients undergoing a

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1987.tb00532.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

SummaryAn enzyme‐linked immunosorbent assay (ELISA) for sheep mast cell proteinase (SMCP) has been developed. Concentrations of SMCP in homogenates of abomasal tissue from parasite‐immune sheep (341 μg SMCP/g tissues) were raised when compared to those in normal (non‐infected) abomasa (0±145 μg SMCP/g tissue). SMCP was not detected in sera from normal animals challenged withHaemonchus contortusbut was present 1±4 ng SMCP/ml) was detected in lymph from 2/3 and 4/5 immune animals between 1 and 4 days post‐challenge with 50000 larvae, but not from normal animals. SMCP was not detected in lymph from immune animals following challenge with 1000Ostertagialarvae. The relatively low concentrations of SMCP in blood and lymph reflect the presence of proteinase inhibitor(s) which interfered wit

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1987.tb00533.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

SummaryThe proteins and antigens of different life stages ofTrichostrongylus colubriformiswere compared with those ofOstertagia circumcinctain an attempt to identify the subset of parasite molecules that is genus‐specific and that may therefore be involved in the induction of genus‐specific, host‐protective immunity. Novel short‐term culture techniques were instituted to label biosynthetically the proteins of the infective larval and adult stages of the parasites using35S‐methionine. High resolution, two‐dimensional electrophoretic profiles of the labelled proteins indicated that the majority of proteins synthesized by adults were also present in the larval stages. Qualitative differences in the levels of these common proteins were observed, indicating differences in protein expression or turnover. There was extensive homology between larvae from the different species, with only eight major differences apparent in their profiles of biosynthetically‐labelled proteins. Western blot analysis using immune sheep sera indicated that extensive homology also existed between the antigens ofT. colubriformisandO. circu

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1987.tb00534.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY