bluuebunny/crossref_metadata_2025 huggingface dataset:
Distribution of intestinal mast cell proteinase in blood and tissues of normal and Trichinella‐intected mice
Authors: HUNTLEY J.F. , GOODEN C. , NEWLANDS G.F.J. , MACKELLAR A. , LAMMAS D.A. , WAKELIN D. , TUOHY M. , WOODBURY R.G. , MILLER H.R.P.
Published: October 2007

Summary A sensitive and specific enzyme‐linked immunosorbent assay (ELISA) was developed for mouse intestinal mast cell proteinase (IMCP). Specificity was demonstrated by the absence of immunoreactivity with extracts of isolated serosal mast cells (SMC), or with high concentrations (50 μg/ml) of the antigenically similar rat mast cell proteinases I or II. The small and large intestines in normal mice were the major sources of IMCP, there being little or no IMCP in non‐mucosal tissues. Concentrations of IMCP in normal (non‐parasitized) mice were low, but were increased 100–1000‐fold in intestines of mice infected 10 days earlier with Trichinella spiralis. The kinetic response of secreted IMCP into the blood of mice following infection with T. spiralis was also studied. Systemic release of IMCP coincided with the immune expulsion of adult worms from the intestine, and peak concentrations (9.45 μg/ml IMCP) occurred 9 days after infection. The tissue distribution of IMCP, its secretion into blood, and its enteric accumulation during parasite infection, are consistent with a mucosal mast cell (MMC) source for IMCP. The results are discussed in the context of similar findings for rat mast cell proteinase II.
Humoral immune responses of Hereford cattle vaccinated with midgut antigens of the cattle tick, Boophilus microplus
Authors: JACKSON L.A. , OPDEBEECK J.P.
Published: October 2007

Summary Vaccination of cattle with midgut membrane (GM) antigen derived from the cattle tick, Boophilus microplus, injected with the adjuvant Quil A, resulted in significant increases in total immunoglobulins, mainly in the IgG1 and IgG2 fractions of the serum. Analysis of the anti‐GM antibody levels of vaccinated cattle showed that the levels of IgG, IgGl and complement‐fixing antibodies were significantly correlated to protection against infestation with cattle ticks. Anti‐GM antibodies of the IgG2 and IgM isotype were not correlated to protection against infestation with cattle ticks. Anti‐GM antibodies fixed complement (C′) in the presence of GM, larval membrane antigen and live, midgut cells, but not in the presence of live, larval cells. Anti‐GM antibodies were able to fix C′ equally well in the presence of GM antigen and live, midgut cells. None of the antigens tested activated the alternate pathway of complement under the conditions tested. Levels of anti‐GM IgG1 antibodies were used to develop a regression model for predicting levels of protection against infestation with cattle ticks in vaccinated cattle.
Humoral and cellular immune response in mice and dogs induced by a recombinant Echinococcus multilocularis antigen produced by a Salmonella typhimurium vaccine strain
Authors: GOTTSTEIN B. , MÜLLER N. , CRYZ S.J. , VOGEL M. , TANNER I. , SEEBECK T.
Published: October 2007

Summary A gene fragment (II/3–10) from the cestode Echinococcus multilocularis coding for a species‐specific antigen was expressed in the live attenuated Salmonella typhimurium vaccine strain LT2 M1C. The recombinant vaccine (S. typhimurium+ pVM II/3–10) was assessed for its potential to induce both a humoral and cell‐mediated immune response in mice and dogs. Both subcutaneous and peroral administration of the vaccine resulted in antibody synthesis and lymphocyte priming of C57BL/6J mice against S. typhimurium antigens as well as against the recombinant E. multilocularis antigen. Two vaccinated (subcutaneous and peroral) dogs showed a strong humoral immune response to S. typhimurium antigens and to the recombinant E. multilocularis antigen, but proliferation of peripheral blood lymphocytes was not detectable against the bacterial S. typhimurium antigens. Regarding the recombinant E. multilocularis antigen, borderline lymphocyte proliferation was demonstrated following subcutaneous and none following peroral administration of the recombinant vaccine to dogs.
The adoptive transfer of T‐cell dependent immunity to Plasmodium chabaudi chabaudi in CBA/Ca mice is achieved only after superinfection of immune spleen cell donors
Authors: FAVILA‐CASTILLO L. , JARRA W. , BROWN K.N.
Published: October 2007

Summary The transfer of spleen cells from CBA/Ca mice recovered from a P. c. chabaudi AS primary infection into irradiated syngeneic recipients conferred very poor protection. Neither elimination of Ly2 cells from immune spleen cells nor reinfection of the donors some days before transfer improved protection significantly. Significant protection was transferred with spleen cells from donors which had been infected 7 times prior to cell transfer. Transferred protection was reduced or eliminated by pretreatment of cells with anti‐Thy‐1 or anti‐L3T4 monoclonal antibodies but not with anti‐Ly2.
Suppression of macrophage‐mediated antibody‐dependent killing of Schistosoma mansoni larvae by concanavalin A stimulated spleen cell‐derived factor(s)
Authors: WATANABE TADASHI , YAMASHITA TAKAO , SENDO FUJIRO
Published: October 2007

Summary Culture supernatants (sup) from rat spleen cells stimulated with concanavalin A (Con A) sepharose 4B suppressed schistosomulum killing by macrophages in a system of antibody‐dependent cell‐mediated cytotoxicity (ADCC). (a) The suppressive effect of the sup was strongest when they were added to cultures at the start of the ADCC assay, and it was decreased when sup were added to cultures in which the ADCC assay had begun more than 3 h previously, (b) From the results of various experiments in ADCC reaction, it was suggested that the suppressive factor(s) inhibited at least in part the interaction between macrophages and antibodies which had been bound to schistosomula, and that the suppressive factor(s) was bound to the macrophage side, (c) The suppressive activity was partially inactivated by treatment at 56°C for 30 min, and it was lost almost completely by the treatment at 100°C for 10 min. (d) The suppressive factor(s) differed from known cytokines such as interleukin 1 (IL‐1), interleukin 2 (IL‐2), granulocyte‐macrophage‐colony stimulating factor (GM‐CSF), interferon‐γ (IFN‐γ), and tumour necrosis factor (TNF).
Establishment of Theileria‐infected bovine cell lines in scid mice
Authors: FELL A.H. , PRESTON PATRICIA M. , ANSELL J.D.
Published: October 2007

Summary Bovine cells tranformed by infection with the protozoan parasite Theileria annulata were inoculated subcutaneously or intraperitoneally into C.B.‐17 scid mice. Mice injected subcutaneously developed solid tumours at the injection site, whilst those injected intraperitoneally developed ascites. Schizont‐infected cells were found in other tissues: infected cells spread much more easily from the intraperitoneal site. Karyotyping of cells isolated from tumours showed no evidence of transfer of parasites to murine cells. These results show that the scid mouse can be used as a host for Theileria‐infected bovine cells.
An antigen specific to the liver stage of rodent malaria recognized by a monoclonal antibody
Authors: SUHRBIER A. , WINGER L. , O'DOWD C. , HODIVALA K. , SINDEN R.E.
Published: October 2007

Summary Vaccines currently being evaluated against malaria are based on proteins derived from the blood, sporozoite and sexual stages. Antigens from the liver stage, which is now recognized as the major target of protective sporozoite induced immunity, have received comparatively little attention. This paper describes the generation of a monoclonal antibody (MoAb), which recognizes an antigen specific to the liver stage of the rodent malaria Plasmodium berghei. The antigen is expressed throughout liver stage development and appears to be localized to the parasitophorous vacuole membrane. The MoAb did not affect the growth of liver stages cultured in vitro nor could protection be demonstrated in vivo following passive transfer of the antibody.
Antibody isotype responses to the Schistosoma mansoni schistosomulum in the CBA/N mouse induced by different stages of the parasite life cycle
Authors: MAZZA G. , DUNNE D.W. , BUTTERWORTH A.E.
Published: October 2007

Summary During infection with Schistosoma mansoni the extent and nature of immune reactions against schistosomula may be influenced by responses to cross‐reactive antigens in eggs or adult worms, and there is now extensive evidence for cross‐reactivity between the different stages of the parasite life cycle. In this study IgM and IgG subclass antibodies produced in (CBA/N × Balb/c) Fl male and female mice were measured over a period of time following exposure to a chronic infection, to unisexual male cercariae or to irradiated larvae. Antibody levels were also measured following immunization with antigen preparations derived from adult worms, schistosomula or eggs. (CBA/N × Balb/c) Fl male mice exhibit an X‐linked immune deficiency which results in an inability to respond to T‐independent (TI) type 2 polysaccharides. Isotype levels were measured by ELISA to detergent‐soluble schistosomulum antigen. Results showed that antigens on the different stages of the parasite life cycle have a qualitative influence on the antibody response to the larval surface, and that T‐independent type 2 polysaccharides, particularly abundant in egg. exhibit antigen‐directed isotype restriction in the form of IgM and IgG3 antibodies.
Properties of epitopes of Pfs 48/45, a target of transmission blocking monoclonal antibodies, on gametes of different isolates of Plasmodium falciparum
Authors: CARTER RICHARD , GRAVES PATRICIA M. , KEISTER DAVID B. , QUAKYI ISABELLA A.
Published: October 2007

Summary We have studied the properties of epitopes on Plasmodium falciparum gamete surface protein Pfs 48/45, a target antigen of malaria transmission blocking antibodies. Using a two site immunoradiometric assay we have defined three spacially separate, non‐repeated, epitope regions on the peptides representing this antigen. Epitope region I is a target of monoclonal antibodies (MoAbs) which strongly suppress infectivity of gametocytes of P. falciparum to mosquitoes; the effect is complement independent and is mediated as effectively by the monovalent Fab fragments as by intact MoAb. Epitope region II consists of two spacially close subregions, Ha and lib; variant forms of epitopes Ha and lib occurred in different isolates of P. falciparum. Epitope region III also showed slight structural modification between isolates. MoAbs against regions II or III were relatively ineffective in suppressing gametocyte infectivity compared to MoAbs against region I. However, certain combinations of MoAbs against regions II and III together acted synergistically to suppress infectivity to mosquitoes. All these epitopes failed to react with MoAb when the antigen was presented in reduced form. A fourth epitope, however, was identified which reacted strongly with MoAb when the antigen was presented in reduced form. The MoAb against this epitope had no effect on the infectivity of gametocytes of P. falciparum to mosquitoes.
Oxygen derived free radicals and the course of Eimeria vermiformis infection in inbred strains of mice
Authors: OVINGTON K.S. , SMITH N.C. , JOYSEY H. S.
Published: October 2007

Summary Free radical generation by peritoneal leukocytes from BALB/c and C57BL/6 mice was monitored for 18 days following infection with Eimeria vermiformis. Free radical generation occurred earlier and was quantitatively much greater in resistant BALB/c mice than in susceptible C57BL/6 mice, resistance being indicated by a much lower oocyst production and a shorter patent period of E. vermiformis. Plasma greatly enhanced free radical generation in response to a soluble antigen prepared from sporulated oocysts indicating the presence of plasma‐borne factor(s) which enhance free radical generation in response to E. vermiformis.
Increased frequency of HLA‐DR3 and complotype SC01 in Mexican mestizo patients with amoebic abscess of the liver
Authors: ARELLANO J. , GRANADOS J. , PÉREZ E. , FÉLIX C. , KRETSCHMER R.R.
Published: October 2007

Summary Our preliminary study (31 patients) of HLA frequencies and amoebic abscess of the liver (AAL) in Mexican mestizos was extended to include 110 patients with this condition. The previously found increase in H LA‐B16 was not confirmed, but the frequency of HLA‐DR3 was again found significantly increased in patients with AAL when compared to the normal, ethnically matched control population, both in its isolated (35‐5% vs 12.7%) and in the HLA‐A2, DR3 haplotypic version (20.9% vs 4.5%). Moreover, seven of the 17 HLA specificities that were found to be individually different at P (yet not at PC) level in patients with AAL when compared to the control population, were actually HLA‐DR3 containing haplotypes. HLA‐DR3 may thus encode a risk factor(s) for AAL, at least in the Mexican mestizo population. Furthermore a significant increase in the complotype SC01 and its haplotypic version SC01, DR4 were identified in 45 non selected patients with AAL when compared to normal controls (31‐1% vs 6.7% and 17.8% vs 0% respectively). Even though a relationship between allelic forms of complement components and their function has not been fully established, this complotype could represent a risk factor as well, since complement appears to play a role in host defence against amoebic invasion. Finally, no extended haplotype preference was found in these AAL palients.
Free‐living amoebae: pathogenicity and immunity
Authors: FERRANTE A.
Published: October 2007

Summary Free‐living amoebae cause three well‐defined disease entities: (i) primary amoebic meningoencephalitis. caused by Naegleria fowleri, (ii) granulomatous amoebic encephalitis and (iii) chronic amoebic keratitis, caused by species of Acanthamoeba. Both Naegieria infections and chronic amoebic keratitis occur in healthy individuals while granulomatous amoebic encephalitis is often associated with patients with acquired immunodeficiencies. The different pathogenic behaviour of these organisms is associated with differences in life cycle, amoeboidal locomotion, enzyme composition (such as phospholipase A), and cytotoxins, as well as natural host immunity. Immunity against these amoebae (whether acquired or natural) involves a combination of complement, antibody and cell‐mediated immunity. Evidence suggests that the major mechanisms of immunity against these amoebae is activation of phagocytic cells, especially neutrophils, by lymphokines and opsonization of the amoebae by antibody which promote an antibody dependent cellular destruction of the organism.
Inhibitory activity of IL‐6 on malaria hepatic stages
Authors: PIED SYLVIANE , RENIA LAURENT , NUSSLER ANDREAS , MILTGEN FRANÇOIS , MAZIER DOMINIQUE
Published: October 2007

Summary Addition of recombinant inlcrleukin‐6 (IL‐6) to Plasmodium yoelii hepatic cultures resulted in a specific dose‐dependent inhibition of parasite development. Time course experiments showed that, without any direct effect on free sporozoites, IL‐6 exerts its action during both the early phase of infection and during the subsequent maturation of the schizonts. Elicitation of the oxidative burst appears lo be one mechanism by which IL‐6 interferes with the development of hepatic phase. Catalase and superoxide dismutase, two scavengers of hydrogen peroxide and superoxide anions, reversed the IL‐6 mediated parasiticidal activity.
Characteristics and specificity of hybridoma antibodies against oocyst antigens of Cryptosporidium parvum from man
Authors: MCDONALD V. , DEER R.M.A. , NINA J.M.S. , WRIGHT S. , CHIODINI P.L. , McADAM K.P.W.J.
Published: October 2007

Summary Hybridoma antibodies (HAbs) against oocyst antigens of a human isolate of Cryptosporidium parvum were 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 cryptosporidiosis.
Age‐specific acquisition of immunity to infective larvae in a bancroftian filariasis endemic area of Papua New Guinea
Authors: DAY KAREN P. , GREGORY WILLIAM F. , MAIZELS RICK M.
Published: October 2007

Summary The 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 constiluent.
Antibody responses to Plasmodium falciparum gametocyte antigens during and after malaria attacks in schoolchildren from Madang, Papua New Guinea
Authors: GRAVES P.M. , DOUBROVSKY A. , BECKERS P.
Published: October 2007

Summary Sera 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) to Plasmodium falciparum gametocytes. 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 epitopes on the same molecule.
Serum antibody response in children with Giardia lamblia infection and identification of an immunodominant 57‐kilodalton antigen
Authors: CHAR SHOBHA , SHETTY NANDINI , NARASIMHA MAITHREYI , ELLIOTT ELIZABETH , MACADEN RAGINI , FARTHING MICHAEL J.G.
Published: October 2007

Summary Giardia lamblia antigens 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 cytoskeleton.
Direct lysis of Trypanosoma cruzi: a novel effector mechanism of protection mediated by human anti‐gal antibodies
Authors: GAZZINELU R.T. , PEREIRA M.E.S. , ROMANHA A. , GAZZINELLI G. , BRENER Z.
Published: October 2007

Summary Anti‐gal antibodies directed against a carbohydrate epitope present in mouse laminin (galactosyl α 1‐3 galactose) and detected in high levels in sera from patients in the acute phase of Chagas disease are responsible for the direct lysis (DL) of Trypanasoma cruzi blood forms independent of either the classic or alternative complement pathways. Furthermore, the lectins Euonymus europaeus (EE) specific for the carbohydrates gal α1‐3 gal present a similar lytic activity against T. cruzi at the same concentrations of purified anti‐gal antibodies. The DL activity was tested with several other lectins but Concanavalin A (Con A) specific for α‐D‐mannose and α‐D‐glucose was the only one also presenting lytic activity. The lectins and anti‐gal antibodies lytic activity can be inhibited by specific carbohydrates suggesting that this phenomenon is related to the capability of these lectins or anti‐gal antibodies to bind to a crucial surface component of T. cruzi. Moreover, the infectivity of T. cruzi blood forms to mice was clearly inactivated by incubation with acute chagasic sera (ACS) but not by ACS absorbed by immunoaffinity chromatography with mouse laminin, a strong evidence that high levels of anti‐gal antibodies participate in the decline of the parasitaemia from the acute to the chronic phase in Chagas disease.
Testosterone and other gonadal factor(s) restrict the efficacy of genes controlling resistance to Plasmodium chabaudi malaria
Authors: WUNDERLICH FRANK , MARINOVSKI PREDRAG , PETER W. , BENTEN M. , SCHMITT‐WREDE HANS‐PETER , MOSSMANN HORST
Published: October 2007

Summary The effect of circulating concentrations of testosterone (Te) on resistance to Plasmodium chabaudi malaria was investigated in the H‐2 congenic mouse strains C57BL/1, B10.A. 10.A(3R). B10.A(4R), and B10.D2. Te‐levels were determined by radioimmunoassay and resistance was expressed in terms of percent self‐healers after challenge with 106P. chabaudi‐infected erythrocytes. Our data indicate: (i) Females and castrated males reveal very similar interstrain variations of resistance. These do not correlate with the interstrain variations of the Te‐levels. This is consistent with the view that resistance to P. chaubaudi is controlled by genes of the H‐2 complex and genes of the non‐H‐2 B10‐background, (ii) The polygenic control of resistance is inefficacious at high Te‐levels. This is evident as high susceptibilities of males, Te‐treated females and Te‐treated castrated males. Moreover, high Te‐levels correlate with susceptibilities to P. chabaudi within mice of the same sex of a given strain, (iii) BlO‐males chemically castrated using buserdin display the same low Te‐leveel as those surgically castrated. The latter become resistant, while the former remain as highly susceptible to P. chabaudi is untreated B10‐males. Obviously, other gonadal factor(s), besides Te, impose restrictions on genes controlling resistance to P. chabaudi malaria.
Humoral immune responses in human infection with the whipworm Trichuris trichiura
Authors: LILLYWHITE J.E. , BUNDY D.A.P. , DIDIER J.M. , COOPER E.S. , BIANCO A.E.
Published: October 2007

Summary The humoral immune response to infection with Trichuris trichiura was investigated by ELISA and immunoblotting using human sera from the Caribbean island of St Lucia. Immunoblot analysis of the degree of cross‐reactivity with the related trichuroid Trichinella spiralis and with the other commonly co‐existent nematodes. Ascaris lumbricoides and Toxocara canis, was carried out using selected sera. The IgM, IgA, IgE, and IgG subclass antibody levels were measured in ELISA using a detergent solubilized extract of adult T. trichiura. The IgG and IgE responses were highly Trichuris specific. Anti‐T. trichiura IgM responses were totally cross‐reactive with A. lumbricoides and were completely ablated by pre‐incubation of sera with Ascaris antigen. The IgG response was predominantly of the IgG1 subclass with a minimal IgG3 response. Only 1 person out of 130 tested had a delectable IgG3 response. The IgG2 response appeared to be directed primarily against carbohydrate or polysaccharide antigens as pre‐treatment of the ELISA plates with poly‐L‐lysine was necessary before a response could be detected. These data are the first demonstration of human isotypic responses to infection with T. trichiura.
Immunochemical localization of major hydatid fluid antigens in protoscoleces and cysts of Echinococcus granulosus from human origin
Authors: SANCHEZ F. , MARCH F. , MERCADER M. , COLL P. , MUÑOZ C. , PRATS G.
Published: October 2007

Summary Monospecitic 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 of E. granulosus from 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 discussed.
Genetic control of acquired resistance to haemonchosis in Merino lambs
Authors: GILL H.S.
Published: October 2007

Summary Parasitological and immune‐logical responses of genetically resistant and random‐bred lambs to primary and secondary infection with H. 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‐Haemonchus antibodies correlated positively with the resistance status of the host. Taken together these results suggest that the genetic resistance of sheep to H. contorius results 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 to haemonchosis.
Age‐dependency of infection status and serum antibody levels in human whipworm (Trichuris trichiura) infection
Authors: BUNDY D.A.P. , LILLYWHITE J.E. , DIDIER J.M. , Simmons I. , Bianco A.E.
Published: October 2007

Summary This 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 with Ascaris lumbricoides adult 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, respectively.
Macrophage activation in vivax malaria: fever is associated with increased levels of neopterin and interferon‐gamma
Authors: BROWN ARTHUR E. , TEJA‐ISAVADHARM PAKTIYA , WEBSTER H.KYLE
Published: October 2007

Summary In 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 with Plasmodlum vivax parasitaemia. 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 neopterin excretion.
Schistosoma japonicum (Chinese strain): characterization of two monoclonal antibodies which recognized common epitopes in the tegument of adult worms and schistosomula
Authors: VIYANANT V. , SOBHON P. , UPATHAM E.S. , KUSAMRAN T.
Published: October 2007

Summary Two monoclonal antibodies have been produced that bind to the common epitopes on adult and schistosomula of S. japonicum (Chinese strain). The isotypes of these monoclonal antibodies were determined to be IgM (designated SG9‐5) and IgG2a (designed 9E7) respectively. The target epitopes of 8G9‐5 and 9E7, as analysed by immunoblolling assay, are at M, of 64 k Da and 54 kDa respectively. Indirect immunofluorescence assay using frozen sections of adult worms, intact mechanically transformed schistosomula and 5‐day‐old lung schistosomula indicated that both epitopes are located in the tegument of both stages of parasite. These epi topes appear to be two of several major immunogenic proteins on the tegument of both young and adult worms.
A specific T‐cell receptor genotype preference in the immune response to a synthetic Plasmodium falciparum malaria vaccine
Authors: MURILLO LUIS A. , TENJO FERNANDO A. , CLAVIJO OLGA P. , OROZCO MAURICIO A. , SAMPAIO SILVIA , KALIL JORGE , PATARROYO MANUEL E.
Published: October 2007

Summary In recent studies with 63 and 122 volunteers vaccinated with the SPf 66 synthetic malaria vaccine, specific antibody patterns were classified as high or low responders. Using the Polymerase Chain Reaction (PCR), a specific and selective preference was shown for the Vβ arrangement of the T‐cell receptor in the high responder group involving the Vβ‐8 gene. The low responder group showed the rearrangement of a different set of genes, and a particular association with Vβ‐10.
Changes in the protein profile and antigenicity of different Borrelia burgdorferi strains after reintroduction to Ixodes ricinus ticks
Authors: HU CHANG MIN , GERN LISE , AESCHLIMANN ANDRÉ
Published: October 2007

Summary Eight Swiss strains of Borrelia burgdorferi, with various protein profiles and the North‐American strain B31 were artificially introduced into Ixodes ricinus ticks and reisolated 10 days later. All isolates were subsequently examined by SDS‐PAGE analysis. Comparing initial isolates with the reisolates, we observed that 7 out of 9 strains changed their protein pattern with respect to the major proteins OspA, OspB and the 22 kDa protein after passage in the tick. The strains NE2, NE4 and NE83 with the initial phenotype of OspA and 22 kDa proteins changed to the phenotype of OspA and OspB, the strains B2 and NE202 with the initial phenotype of OspA acquired an additional protein of 22 kDa and the strain NE58 with the initial phenotype of OspA also acquired a protein of 22 kDa. Examination of these isolates by Western blot analysis demonstrated that the reaction with the monoclonal antibody H5332 and a monospecific polyclonal antibody PoAb/anti‐22 kDa differed between the initial isolates and the reisolates.
Monoclonal antibodies recognize a processing dependent epitope present in the mature CS protein of various plasmodial species
Authors: TSUJI MORIYA , CORRADIN GIAMPIETRO , ZAVALA FIDEL
Published: October 2007

Summary In 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 vivo assay.
Transmission blocking antibody of the Plasmodium falciparum zygote/ookinete surface protein Pfs25 also influences sporozoite development
Authors: LENSEN A.H.W. , VAN GEMERT G.J.A. , BOLMER M.G. , MEIS J.F.G.M. , KASLOW D. , Th. MEUWISSEN J.H.E. , PONNUDURAI T.
Published: October 2007

Summary The Plasmodium falciparum zygote ookinete surface protein, Pfs25, persists in the oocyst wall throughout its development. Anti‐25 kD transmission blocking antibody, given to infected Anopheles stephensi or A. gambiae mosquitoes 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 effect.
An immunocytochemical test for the diagnosis of antibodies to Plasmodium vivax
Authors: BRACHO CARMEN , PEREZ HILDA
Published: October 2007

Summary An immunocytochemical peroxidase test (ICPT) has been developed to allow serological measurement of the antibody response to Plasmodium vivax by light microscopy. Acetone fixed P. vivax erythrocyte stages were used as source of antigen. The immunofluorescent antibody test (IFAT) was used as reference test. In testing sera from individuals infected with P. vivax in southeastern Venezuela a high correlation (100%) was obtained between the ICPT and the IFAT. There were cross reactions with sera from patients with malaria by P. falciparum but not with those from patients with other parasitic diseases. Antibody titres as measured by the ICPT showed a positive correclation with past P. vivax malarial experiences.
An evaluation of the role of carbohydrate epitopes in immunity to Trichinella spiralis
Authors: JARVIS L.M. , PRITCHARD D.I.
Published: October 2007

Summary A study is described in which the role of carbohydrate epitopes in the generation of protective immunity to Trichinella spiralis was 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 to T. spiralis.
Occurrence and characteristics of hypodense eosinophils in rats infected with Trichinella spiralis
Authors: HAMADA ATSUO , WATANABE NAOHIRO , KOBAYASHI AKIO
Published: October 2007

Summary Hypodense 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 during Trichinella spiralis infection. Hypodense eosinophils were observed in the peripheral blood in association with Trichinella infection. 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.
A theoretical framework for the immunoepidemiology of helminth infection
Authors: WOOLHOUSE M.E.J.
Published: October 2007

Summary Field studies of parasitic helminths in endemically infected human communities have provided quantitative information on the relationships between parasite burdens, immune responses and age. There are considerable difficulties in the interpretation of these immunoepidemiological data due to the complexities of the biological processes generating the observed patterns. In this paper simple mathematical models are used to explore the expected patterns of variation with host age in parasite burdens, the aggregation of parasites among hosts, levels of immune response, and the correlation between parasite burdens and immune responses. These relationships reflect rates of infection, rates of parasite mortality, the strength of the immune response, and the duration of immunological memory. The models generate some complex and counterintuitive patterns. The analysis suggests that some of these patterns might serve to (i) distinguish effects due to acquired immunity from effects due to age‐dependent exposure, (ii) identify potentially protective immune responses, and (iii) identify the parasite stages important in the development of acquired immunity. The results imply that previous analyses of immunoepidemiological data may have been overly simplistic and, especially, that patterns believed to be inconsistent with protective immunity may have been incorrectly interpreted.
Plasma leakage in skin of sheep selected for resistance or susceptibility to fleece rot and fly strike
Authors: COLDITZ I.G. , WOOLASTON R.R. , LAX J. , MORTIMER S.I.
Published: October 2007

Summary The leakage of plasma into skin following injection of histamine, bradykinin, activated complement, platelet‐activating factor and serotonin was measured in sheep bred for resistance or susceptibility to fleece rot and fly strike. Genetically susceptible sheep had significantly greater plasma leakage to activated complement than genetically resistant sheep, and for all mediators there was a trend for plasma leakage to be greater in susceptible sheep. Within each genotype there was also a tendency for plasma leakage to be positively correlated with fleece rot score. In a flock of sheep of different genetic background not selected for resistance or susceptibility to fleece rot and fly strike, positive phenotypic correlations were also noted between fleece rot score and plasma leakage. Plasma leakage provides nutrition for the first instar larvae of Lucilia cuprina, the major cause of primary blowfly strike in Australia. Diminished leakage of plasma following release of endogenous permeability mediators may be one component of the mechanism that confers resistance in animals bred for resistance to fleece rot and fly strike.
Induction of macrophage activation and opsonizing antibodies by Trypanosoma cruzi subpopulations
Authors: CELENTANO ANA MARIA , CAPPA STELLA M. GONZÁLEZ
Published: October 2007

Summary Macrophage activation and production of opsonizing antibodies were studied in mice either infected with a lethal and reticulotropic Trypanosoma cruzi strain, RA, or with a non lethal and myotropic strain, CA‐I, as well as with a clone, K98 (derived from CA‐I), similar to the parental strain. Measurement of macrophage respiratory burst by chemiluminiscence disclosed that T. cruzi infection induced an enhancement of the respiratory burst, no matter the parasite subpopulation employed. But, while in mice surviving RA infection the respiratory burst was higher than during the acute period and parasitaemia was efficiently controlled, in mice infected with K98 enhanced respiratory burst coexisted with measurable levels of parasitaemia either at acute or chronic infection periods. Macrophage activation was also proved by enhanced trypanocidal activity in macrophages derived from mice infected with any of the parasite subpopulations. Sera from RA mice opsonized and lysed T. cruzi bloodstream forms efficiently, whereas sera from CA‐I or K98 mice neither lysed nor opsonized this parasite stage. All three subpopulations assayed here showed IgG bound to their membranes in vivo and similar capping kinetics, but only antibodies bound to RA parasites invariably triggered lysis. Therefore, the role played by macrophage activation in resistance and control of Pm levels is related to some features of each T. cruzi subpopulation, such as its capacity to invade macrophages and to elicit opsonizing antibodies.
Examination of murine antibody response to secondary hydatidosis using ELISA and immunoelectrophoresis
Authors: LIU D. , LIGHTOWLERS M. W. , RICKARD M. D.
Published: October 2007

Summary Antibody responses in mice with up to 64 weeks of secondary Echinococcus granulosus hydatidosis were examined by ELISA using hydatid protoscolex antigen (Px), Antigen 5 (Ag5) and Antigen B (AgB), and by immunoelectrophoresis (IEP) using sheep hydatid cyst fluid (SHCF). Anti‐Px IgG antibodies, evident from 3–5 days post infection (p.i.), increased steadily until 16 weeks and maintained a high level afterwards. Anti‐Ag5 IgG antibodies were negligible up to two weeks, but they showed a small increase around 2–3 weeks which was followed by a big increase around 16 weeks p.i. The high level of anti‐Ag5 IgG antibodies persisted to the end of experiment. The level of anti‐AgB IgG antibodies remained relatively low throughout infection. Anti‐Px IgM antibodies appeared in the early period of infection, but became insignificant as the infection proceeded. Specific IgM antibodies to Ag5 and AgB showed two waves of increase, one between 3 days to 4 weeks p.i. and the other between 16 weeks to 46 weeks p.i. The level of IgA antibodies to Ag5 and AgB was low and only a moderate amount of anti‐Px IgA antibodies was detected. Generally, a higher level of serum antibodies are associated with a larger number of mature cysts. Serum samples from 5 of 8 mice harbouring hydatid cysts formed 1–3 bands with SHCF in IEP, including Arc 5, but a precipitation arc with AgB was not observed. Analysis of hydatid cyst fluid from the infected mice (MHCF) in IEP also failed to demonstrate AgB. Despite the high levels of antihydatid antibodies generated in the infected mice, protoscoleces appeared to be unhindered in their growth to mature cysts.
Immune responses of sheep to surface antigens of infective larvae of Ostertagia circumcincta
Authors: WEDRYCHOWICZ H. , BAIRDEN K. , TAIT A. , HOLMES P. H.
Published: October 2007

Summary Immune responses to surface antigens of infective larvae of Ostertagia circumcincta were studied in 5‐month old Finn‐Dorset male lambs. The sheep were vaccinated subcutaneously with 2 doses of 25 μg/kg body weight of infective larvae surface or somatic extracts and Freund's or beryllium hydroxide adjuvants. It was found that only in lambs vaccinated with L3 surface extracts and beryllium hydroxide as an adjuvant did worm burdens differ significantly (P<0.01) from those of challenge controls (71.7% protection). Sheep vaccinated with the same antigenic preparation but administered with Freund's adjuvant or with beryllium adjuvant and somatic extracts demonstrated rather poor protection (32.4 and 30.5% respectively). All the vaccinated sheep showed a high IgG response to L3 surface antigens while significant levels of serum and bile IgA reacting with the surface extracts were only detected in those lambs vaccinated with L3 surface extracts and beryllium hydroxide. In immunofluorescence tests serum IgA of this group reacted with the whole surface of exsheathed larvae or with the site of opening of excretory pore while IgG antibodies reacted strongly with the anterior and posterior parts of the infective larvae. Both IgA and IgG responses to surface antigens were stage specific.
Alternative patterns of MHC‐restricted antibody responsiveness following intraperitoneal immunization of inbred mice with different preparations of an 86 kilodalton antigen of Schistosoma mansoni
Authors: SCHWEITZER A. NICOLA
Published: October 2007

Summary The investigation of MHC restricted antibody responses to an 86 kDa antigen (p86) during chronic Schistosoma mansoni infection has been extended to immunization with this antigen. In the absence of adjuvant, a similar pattern of responsiveness by mice expressing H‐2k and H‐2d but not H‐2b was observed following immunization with unpurified adult worm homogenate. Adjuvant selectively abrogated the capacity of H‐2d mice to respond and this was also the case when purified p86 with adjuvant was injected. Immunization with purified subfragments of p86 again demonstrated MHC restriction in the capacity to immunoprecipitate p86 in vitro translation product, the pattern varying according to the fragment used. Western blot analysis showed that in some, but not all instances of apparent ‘non‐responsiveness’ characterized by immunoprecipitation, antibody specificities capable of recognizing p86 epitopes on the nitrocellulose bound p86 were, indeed, present. Thus the fine specificity as well as the absolute capacity to respond is influenced by both the MHC haplotype of the host and the nature of the immunizing antigen.
Vaccination of dogs against Babesia canis infection using parasite antigens from in vitro culture
Authors: SCHETTERS TH. P. M. , KLEUSKENS J. , SCHOLTES N. , BOS H. J.
Published: October 2007

Summary Groups of five dogs were vaccinated with different Babesia canis vaccine formulations. It appeared that partial protection against challenge infection was obtained when using parasite antigens from in vitro culture in combination with saponin. Protection was evident as a decrease in parasitaemia after challenge and was associated with the presence of serum antibodies against Babesia parasites. In addition, parasite antigen derived from in vitro culture supernatant exhibited more protective activity than somatic parasite antigen, in that a less marked fall of haematocrit values was found after challenge infection. The fall of haematocrit value observed in the animals immunized with somatic parasite antigen was not different from that observed in the adjuvant control group.