摘要:

SummaryTwenty‐eight nonsibling sheep aged approximately 12 months and raised in a helminth‐free environment were used in two protection studies. Immunizations were conducted by two intramuscular injections 30 days apart with a synthetic 18AA cuticle collagen peptide and native cuticle collagens derived from the third‐ and fourth‐stage larvae of Haemonchus contortus. Ten days following the last immunization, the sheep were each given 500 infectiveH. contortuslarvae per day for five consecutive days by intraruminal injection. Both collagen materials induced antibodies reactive with cuticle collagens; however, neither induced reproducible protection toH. contortusinfections in vaccinated/ infected sheep. In the most extensive test, there were no statisical differences in mean faecal worm egg count for 56 days post worm challenge, in mean numbers ofH. contortusand female fecundity ratios at necropsy of immunized and unimmunized sheep. Failure to reproducibly immunize sheep with cuticle collagens may be due to the inability of antibodies or host immune cells to reach the collagen epitopes in the nematode cuticle without prior surface coat removal as postulated in human nemaiode

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1991.tb00278.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

SummaryHuman neutrophils. alone, did not killTrichomonas vaginalis.More than 90% ofT. vaginalis(105/ml) survived in the presence of 10% normal human serum (NHS) while 90% of these organisms were killed in the presence of a combination of neutrophils (106/ml) and 10% NHS. Mechanisms responsible for this serum‐mediated neutrophil killing ofT. vaginaliswere demonstrated through a process of lucigenin‐amplified neutrophil chemiluminescence. As evidenced by indirect immunonuores‐cence, NHS showed specific immunoglobulin G (IgG) titre of 1:8 forT. vaginalis.Purified IgG, at 1.6 mg/ml, showed no direct opsonizing or lytic effect on ibis organism. Formalin‐fixed trichomonads opsonized by C2 deficient human serum promote 4 times more neutrophil chemiluminescence than those opsonized by Factor B deficient human serum. With the addition of purified IgG (5 mg/ml) neutrophil chemiluminescence was increased by 4 times and further improved trichomonal killing by neutrophils (from 5 ± 4% to 78 ± 16%) via activation of the classical complement pathway, but did not alter that due to activation of the alternative complement pathway. These studies indicate that both an IgG‐enhanced classical complement pathway activation and an antibody‐independent alternative complement pathway activation provide opsonin (C3) forT. vaginalisto facilitate the neutrophil kill

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1991.tb00279.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

SummaryHybridoma antibodies (HAbs) against oocyst antigens of a human isolate ofCryptosporidium parvumwere developed by fusion of SP2/0 mouse myeloma cells and spleen cells from BALB c mice immunized with oocyst homogenates. In an indirect immunofluoreseence antibody test (IFAT), using as antigen a mixture of air‐dried sporozoites and oocysts, HAbs labelled either the oocyst wall or areas of the sporozoite, including the whole organism, the entire surface, a polar region or the interior. Most of the HAbs were specific for the sporozoite surface, and few of them recognized the oocyst wall. In Western blot analysis of oocysl antigens, sporozoite surface‐reactive monoclonal antibodies (MoAbs) recognized one or more of seven polypeptide bands with molecular weights in the range 47‐>200 kD, and all reacted with the 47 kD band. Each of four heterologous parasite isolates had a unique recognition pattern with a panel of MoAbs in IFAT. suggesting antigenic differences may exist between strains of C. panum. The ability to differentiate between parasite isolates by immunological methods might be of value in epidemiological studies of cryptosporid

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1991.tb00280.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

SummaryThe previously observed MHC‐restriction of the antibody response to an 86kDa S. mansoni antigen has been investigated in more detail. The I‐A locus of the H‐2 complex has been implicated as conferring responder or non‐responder status on mice expressing the k and b alleles respectively. Inheritance of responsiveness was dominant over non‐responsiveness. An additional level of complexity was observed in the p86 antibody responder status of individuals within a responding inbred strain. This could not be accounted for directly by the level of patent infection, but showed an inverse correlation with the level of egg output in H‐2kmice. Differential antibody responsiveness to other antigens, between individuals of the same strain, occurred independently of the differential responsive

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1991.tb00281.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

SummaryThe development of antibodies to infective stages of the filarial parasite,Wuchereria bancrofti, with age of the host human population was studied by immunofluorescence. immunoprecipitation and immunoblotting assays. Among individuals under 20 years of age, few had detectable antibodies to the infective (L3) larval surface by IFA: only 2 out of 10 scored positive. However all adults over 20 years) were positive in this assay although the utilization of isotypes varied between different individuals. Whilst antibodies to the L3 surface are therefore acquired after prolonged exposure to infection (>20 years), recognition patterns of L3 surface labelled antigens, measured by immune‐precipitation analysis iodmated proteins on SDS‐PAGE, and of somatic L3 proteins on immunoblots, were equivalent in the two age groups. Thus, a critical surface antigen recognised in an age‐dependent manner, is present on the L3 cuticle but cannot be resolved as a conventional protein or glycoprotem consti

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1991.tb00282.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

SummarySera from 49 school children in Madang, Papua New Guinea with malaria and follow‐up sera from 40 of these cases were tested by competitive ELISA for antibodies capable of inhibiting binding of eight monoclonal antibodies (MoAbs) toPlasmodium falciparumgametocytes. The proportion of sera inhibiting each MoAb ranged from 31‐2% to 85‐7%. Al follow‐up, the proportion of inhibitory sera decreased for 3 MoAbs, did not change significantly for 4 MoAbs and increased for one MoAb. When sera were grouped according to whether the follow‐up blood slide was positive or negative, further trends emerged for MoAbs against the gamete surface antigen Pfs 48/45. Antibody levels to the IA3‐B8 epitope decreased in follow‐up positive cases, but remained unchanged for follow‐up negative cases. The converse was observed for the IIC5‐Biocpitopc with an increase of antibody in follow‐up positive cases and no change in the negative cases. Amount of antibody to the 3G12/58 epitope decreased when the follow‐up was negative but not when it was positive. Increase in antibody to the 3E12/58 epitope occurred al the follow‐up sample irrespective of the blood slide result. Thus four distinct patterns of longitudinal antibody response were observed against four epitop

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1991.tb00283.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

SummarySummary The seroreactivities to Pf 155/RESA antigen and to three oligopeptides (EENV)2, EENVEHDA and K(DDEHVEEPTVA)2, which constitute repeal subunits of the RESA molecule, were investigated between 1980 and 1986 in two cohorts of children (n= 114) with and without monthly chemosuppression (pulsed reduction of parasite load) against malaria from six months to five years of age during development of protective immunity. Serum samples were collected first at half‐yearly and then yearly intervals. Positive immunofluorescence against Pf 155/ RESA (EMIF) was only found in 24% of the samples. The children with chemosuppression were more often seropositive (30%) than the non prophylactic children (17%). This was in contrast to the seroreactivity against crude parasitic antigens which was highest in the non prophylactic children. In these children, there was a general decrease of EMIF litres around two years of age. Immunosuppression by chronic parasitaemia may be suggested as a reason for this. ELISA seroreactivity was found against one, two or three oligopeptides in all children with high EMIF titres (>250) although (EENV)2appeared to best correlate (92%) with the EMIF seropositivity. While EMIF seropositivity only showed partial correlation to immunoprotection against patent parasitaemia in the non prophylactic children, the individual profiles of the seroreactivities to the different specific epitopes of the Pf 155/RESA molecule and their relevance with regards to protective immunity to malaria need to be investigated furthe

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1991.tb00284.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

SummaryA defect in an immune‐mediated, physiological reaction in the small intestine of congenitally immunosuppressed rats has been identified and corrected by recouping the immunological trigger in the mucosa with epithelial effector cells. Antigenic challenge of jejunum from euthymic rats sensitized by infection withTrichinelta spiralisevoked an anaphylactic response in vitro that was characterized by an elevation in transmural short‐circuit current (Isc) and caused by net Cl‐ secretion. In contrast, jejunum from previously infected athymic counterparts failed to respond electrophysiotogically to antigenic stimulation. Passive immunization of athymic rats with anti‐Trichinella serum restored jejunal responsiveness to antigen. Jejunal unresponsiveness to anligcnic challenge in the athymic rat compared with the euthymic rat was not due to a difference in the duration of exposure to the sensitizing antigens, mast cell numbers, inflammation‐related hislological changes nor to reduced responsiveness of epithelium to Cl‐ sccretagogues. Because the transduction of the antigenic signal into epithelial ion transport changes in euthymic rais requires IgE, mucosal mast cells, mast cell‐derived mediators and enteric nerves, the results support the conclusion that an antibody deficiency is the only functional defect preventing the antigen‐induced change in mucosal ion transport in t

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1991.tb00285.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Summary Giardia lambliaantigens which react with sera from children with G. lamblia infection were investigated by sodium‐dodecyl polyacrylamide gel electrophoresis and immunoblotting. Serum IgG, IgM and IgA response to the antigens were immunochemically characterized. Serum antibodies from all giardiasis patients, but none of the controls, was found to react with a 57‐kilodalton antigen. The 57kDa antigen elicited IgG and IgA but not IgM antibodies. The protein nature of the 57kDa antigen was demonstrated by loss of antibody recognition after trypsin treatment of G. lamblia trophozoites. Sub‐cellular fractionation of G. lamblia trophozoites followed by SDS‐PAGE and immunoblotting showed that the 57kDa antigen was probably not a component of the cytos

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1991.tb00286.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

SummaryThree bovine cell lines and four ovine cell lines infected withTheileria parvaorTheileria annulatawere examined for the production ofinierferon (IFN). Biologically active IFN was detected in the tissue culture supernaiants of four of the cell lines. Only one, a bovine cell line infected withT. parva, produced IFN‐y as measured by specific neutralization with a monoclonal antibody to bovine IFN‐y. This observation was confirmed by analysing RNA from the cell lines on Northern blots using an IFN‐y cDNA probe. The other three cell lines which produced IFN were infected with T. annulata. The IFN produced by those lines was not

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1991.tb00287.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY