bluuebunny/crossref_metadata_2025_split huggingface dataset:
Antibody responses to invariant antigens of Trypanosoma congolense in cattle of differing susceptibility to trypanosomiasis
Authors: AUTHIÉE EDITH , MUTETI DAVID K. , WILLIAMS DIANA J. L. 
Published: October 2007

SummaryFive trypanotolerant N'Dama (Bos taurus) and five susceptible Boran (Bos indicus) cattle were challenged by tsetse flies infected with Trypanosoma congolense IL 13‐E3. These animals had experienced five previous infections with T. congolense, each terminated by drug therapy. Immunoblotting and ELISA were used to determine isotype and specificity of antibody responses to trypanosome invariant antigens. Both IgM and IgG1 were elicited, but the IgG1 responses were directed against a greater diversity of antigens. A 69 kD antigen was the major invariant antigen which elicited IgM antibodies in both breeds, but the N'Damas also responded with high levels of specific IgG1. Analysis of isotypic responses to whole trypanosome extract also revealed lower levels of IgG1 and higher levels of IgM in the Borans than in the N'Damas, suggesting that a dysfunction in the switch from IgM to IgG might occur in infected Boran cattle. A 33 kD antigen appeared to elicit only IgG1. Sera from all five N'Damas and the two Borans which were most resistant to the disease reacted with this antigen prior to and following re‐infection. Furthermore, during the primary T. congolense infection in the same animals, anti‐33 kD antibodies were detectable in all five trypanotolerant N'Damas, but in none of the five susceptible Borans. Thus, the presence of antibodies to the 33 kD antigen ofT. congolense appeared to be associated with a capacity to control the disease.
Host genetics and resistance to acute Trypanosoma cruzi infection in mice. I. Antibody isotype profiles
Authors: POWELL MALCOLM R. , WASSOM DONALD L. 
Published: October 2007

SummarySome strains of inbred mice survive acute infection with Trypanosoma cruzi while others die within a few weeks after infection. Mice which express B10 background genes and either the H‐2q or H‐2d haplotypes are resistant and survive. However, mice which share the B10 genetic background but express H‐2k alleles die, usually within 4 weeks following infection. These data confirm that at least 1 gene in the major histocompatibility complex can determine whether an animal lives or dies during the acute phase. Expression of the H‐2q haplotype on the B10 genetic background or in DBA/l mice is associated with resistance, but H‐2q mice expressing the C3H background are susceptible. Therefore, at least I gene in the genetic background also influences resistance. Our data suggest that genes associated with resistance must be present in both the MHC and the genetic background or the animal will die. The isotypes and specificities of parasite reactive antibodies found in the serum of different inbred mouse strains were assessed during acute infection. Levels of IgM were higher in sera from mice which express the resistant B10 background than in sera from mice expressing the susceptible C3H background. Conversely, mice which share the C3H background genes produced high levels of anti‐parasite IgG2a when compared to B10 congenic strains. Antigen specificity, however, may be influenced by both background and MHC genes, as congenic strains expressing different MHC haplotypes recognized different constellations of T. cruzi antigens. These data suggest a correlation between genes which influence antibody specificity or isotype and the genes which determine the ability of various inbred mouse strains to survive acute infection with T. cruzi.
Synthetic peptides based on conserved Plasmodium falciparum antigens are immunogenic and protective against Plasmodium yoelii malaria
Authors: CHAUHAN VIRANDER S. , CHATTERJEE SHYAMA , JOHAR PARAMJEET K. 
Published: October 2007

SummaryTwo synthetic polypeptides containing multiple B‐ and T‐cell epitopes derived from the conserved regions of two vaccine candidate antigens namely MSA‐1 and RESA of human malarial parasite P. falciparum were studied for immunogenicity and protectivity. Both constructs elicited strong antibody and lymphocyte proliferation responses in BALB/c mice immunized with the carrier‐free peptides. In an ELISA, these peptides also bound antibodies present in the sera from the P. vivax infected humans as well as from the P. yoelii infected mice. Significantly, our data showed that immunization of mice with these P. falciparum peptide could impart partial protection against P. yoelii challenge infection. Our finding that synthetic peptides representing portions of P. falciparum antigens were capable of stimulating protective immune responses against rodent malaria suggests that murine malaria model P. yoelii may provide a suitable system for primary screening of potentially protective synthetic immunogens.
Anisakis simplex: antigen recognition and antibody production in experimentally infected mice
Authors: IGLESIAS R. , LEIRO J. , UBEIRA F. M. , SANTAMARINA M. T. , SANMARTÍN M. L. 
Published: October 2007

SummaryThe kinetics of antibody response to intraperitoneal infection of mice with third stage larvae of Anisakis simplex was investigated by ELISA. Maximum antibody response to excretion‐secretion (ES) antigens was reached before maximum response to somatic (SA) antigens. Total immunoglobulin (Ig) production (consisting mainly of IgM and IgG1 isotypes) was very similar in both cases. Immunoblotting was used to characterize the antigens recognized by the host in the presence or absence of the metabolic products released by the parasite in vivo. Sera from mice infected with live larvae (anti‐L3 L serum) and immunized with dead larvae (anti‐L3 D serum) recognized a similar pattern of bands in immunoblots of ES and SA antigen preparations. In the latter, however, three bands at 14, 17 and 18 kD were only recognized by the anti‐L3 L serum. A possible explanation is that these low molecular weight antigens are ES products released only in vivo. Finally, the immune response in mouse was compared using ELISA and immunoblotting with the response of a human anisakiasis reference serum, and was found to display considerable similarities. This suggests that the mouse may be a useful model for studying the immunobiology of A. simplex in man.
IgE responses in cats infected with Brugia pahangi
Authors: BALDWIN C. I. , DE MEDEIROS FILOMENA , DENHAM D. A. 
Published: October 2007

SummaryPassive cutaneous anaphylaxis tests were used to examine the IgE responses of cats repeatedly infected with the filarial nematode Brugia pahangi. Specific IgE was usually detected only in those cats that killed their adult worms and rarely in those cats in which adult worms survived for long periods. We suggest that this specific IgE is actively involved in killing adult worms in the lymphatics.
Influence of genes within the MHC on mortality and brain cyst development in mice infected with Toxoplasma gondii: kinetics of immune regulation in BALB H‐2 congenic mice
Authors: BLACKWELL JENEFER M. , ROBERTS CRAIG W. , ALEXANDER JAMES 
Published: October 2007

SummaryPrevious work has shown that genes within the major histocompatibility complex (MHC) of the mouse influence resistance and susceptibility to Toxoplasma gondii infection. Initial studies presented here using B10 H‐2 congenic and recombinant haplotype mice inoculated via the oral route with the low virulence Beverley strain of T. gondii confirm the D region localization of MHC‐linked control of brain cyst number. All B10 mice were, however, exquisitely sensitive to minor changes in virulence of the parasite inoculum resulting in high mortality during the early acute phase of infection. Further experiments examining mortality and brain cyst number in BALB MHC congenic mice inoculated via different routes indicated that the BALB background would provide a more favourable genetic environment in which to analyse kinetics of MHC controlled immune regulation following infection via the natural (oral) route. In studies comparing d and k haplotype mice a dramatic inverse relationship between splenic CD4:CD8 T cell ratios and brain cyst number was observed, particularly in the strain (BALB/K; H‐2k) most susceptible to high brain cyst numbers and subsequent toxoplasmic encephalitis. Of particular interest was the observation that splenomegaly and the relative increase in the splenic CD8 T cell population preceded and accompanied the very dramatic and rapid increase in brain cyst formation. The results suggest that the too rapid development of a potent anti‐parasite response in the viscera may drive the parasite to encyst in the brain.
Ablation of eosinophils with anti‐IL‐5 antibody enhances the survival of intracranial worms of Angiostrongylus cantonensis in the mouse
Authors: SASAKI OSAMU , SUGAYA HIROKO , ISHIDA KAZUTO , YOSHIMURA KENTARO 
Published: October 2007

SummaryEffects of depressed eosinophilia on the development of Angiostrongylus cantonensis in the mouse were studied using monoclonal rat anti‐mouse‐interleukin‐5 antibody (anti‐IL‐5). The administration of anti‐IL‐5 strongly depressed peripheral, cerebrospinal fluid (CSF) and medullary eosinophilic responses in mice infected with A. cantonensis, when compared with groups treated with phosphate‐buffered saline solution (PBS) alone or isotype‐matched rat IgG. There was no significant difference in A. cantonensis antigen specific IgG and IgE antibody responses between rat IgG treated and anti‐IL‐5 treated mice. Intracranial worm recovery in anti‐IL‐5 treated mice was consistently high throughout the course of the study and some worms migrated from the brain to the lungs. By contrast, almost all the intracranial worms in the mouse groups treated with PBS alone or rat IgG died before day 32. These data clearly indicate that IL‐5 is essential for eosinophil responses in A. cantonensis infected mice and also that eosinophils serve as a potential effector cell in the killing of the intracranial worms in mice.
Epitope specificity and capacity to inhibit parasite growth in vitro of human antibodies to repeat sequences of the Plasmodium falciparum antigen Ag332
Authors: AHLBORG NIKLAS , FLYG BIRGITTA WÅHLIN , IQBAL JAMSHAID , PERLMANN PETER , BERZINS KLAVS 
Published: October 2007

SummaryIt has earlier been shown that the Plasmodium falciparum‐reactive human monoclonal antibody 33G2 inhibits parasite growth in vitro as well as cytoadherence of infected red blood cells to melanoma cells in vitro. MoAb 33G2 recognizes an epitope of the P. falciparum antigen Ag332 and cross‐reactive determinants in Pf 155/RESA and Pf 11.1 located in repetitive regions containing sequences of regularly spaced pairs of glutamic acid. To study whether antibodies of this specificity frequently occur in human immune sera and if they could be of importance for protective immunity, antibodies were affinity purified on MoAb 33G2 reactive Ag332 peptides. The epitope specificity of the affinity purified antibodies, determined by the Pepscan method, resembled that of MoAb 33G2, but showed differences in fine specificity. The antibodies cross‐reacted to some extent with Pf 11.1 and Pf 155/RESA repeat peptides as detected by peptide ELISA and Pepscan. In indirect immunofluorescence all purified antibodies displayed a dotted pattern of staining of late stage infected red blood cells of two lines of the P. falciparum strain FCR3, including a Pf 155/RESA deficient line. The in vitro growth of these two lines was efficiently inhibited by the affinity purified antibodies, indicating that their inhibitory effect was mainly due to reactivity with antigens other than Pf 155/RESA. This, and the fact that Pf 11.1 has been shown not to be expressed by the asexual stages suggests that Ag332 may be an important target for potentially protective antibodies in vivo and that Ag332 based immunogens are of interest for development of malaria subunit vaccines.
Immunological relationships during primary infection with Heligmosomoides polygyrus (Nematospiroides dubius): downregulation of specific cytokine secretion (IL‐9 and IL‐10) correlates with poor mastocytosis and chronic survival of adult worms
Authors: BEHNKE J. M. , WAHID F. N. , GRENCIS R. K. , ELSE K. J. , BEN‐SMITH A. W. , GOYAL P. K. 
Published: October 2007

SummaryMice were infected either with Trichinella spiralis (day 0). Heligmosomoides polygyrus (day – 14) or concurrently with both species and were killed in groups, together with naïve control mice, on 2 occasions (day 8 and 15 post infection with T. spiralis, corresponding to days 22 and 29 p.i. with H. polygyrus). The expulsion of T. spiralis was slowed significantly in concurrently infected mice and this was associated with a reduced mastocytosis and lower serum mucosal mast cell protease levels. Mesenteric lymph node (MLN) lymphocytes from all three experimental groups secreted IL‐3 and IL‐4 in copious amounts when stimulated in vitro by Concanavalin A (Con‐A), but the secretion of high levels of IL‐9 and IL‐10 was essentially confined to mice infected with T. spiralis alone. It is suggested that adult H. polygyrus selectively modulate cytokine secretion by Th2 cells within the MLN during infection and that this is brought about as a direct consequence of the mechanism employed by H. polygyrus to depress mucosal inflammatory responses in order to facilitate its own survival.
The effect of irradiation on the third stage larvae of Brugia pahangi
Authors: DEVANEY E. , BANCROFT A. , EGAN A. 
Published: October 2007

SummaryThe effect of irradiation on the third stage larvae of the filarial nematode Brugia pahangi was investigated. Labelling with 33S methionine of control or irradiated L3, post‐infective L3 or L4 revealed no consistent alterations in the pattern of proteins synthesized. The only significant difference observed was in 125I labelling, where the specific activity of labelling of soluble cuticular proteins was lower in irradiated than in control parasites. This difference may be related to the reduced size of irradiated parasites rather than to a specific effect of irradiation on the expression of cuticular proteins. Irradiated parasites recovered on day 14 post‐infection were significantly shorter than control parasites. Irradiation also appeared to have a lethal effect on male parasites, as no recognizable males were recovered from animals given irradiated L3, nor were microfilariae ever observed in these animals. The mechanisms by which irradiation may enhance the immunogenicity of L3 of filarial nematodes are discussed.
Antibody responses to a 33 kDa cysteine protease of Trypanosoma congolense: relationship to ‘trypanotolerance’ in cattle
Authors: AUTHIÉ EDITH , DUVALLET GÉRARD , ROBERTSON CHRIS , WILLIAMS DIANA J. L. 
Published: October 2007

SummaryA cysteine protease of Trypanosoma congolense (congopain) elicited IgG1 antibodies in those cattle which exhibited a degree of resistance to disease during experimental infections (Authié et al. 1992, 1993). The aim of the present study was to investigate further the association between anti‐congopain antibodies and resistance to trypanosomiasis, and to provide a lead into the mechanisms responsible for the differential responses to congopain in cattle. Isotype characteristics and kinetics of the antibody response to congopain were studied in three N'Dama (trypanoresistant) and three Boran (susceptible) cattle during primary infection with T. congolense ILNat 3.1. In both groups an IgM response to congopain was elicited, thus demonstrating that congopain is antigenic in both types of cattle. Most of the IgM appeared to be incorporated into immune complexes. IgG was detected as free antibody; IgG1 but not IgG2 was detected. All three N'Dama, but none of the three Boran cattle, mounted a significant IgG response to congopain. Sera from 70 primary‐infected cattle belonging to five breeds of differing susceptibility were tested for their reactivity to congopain. High levels of IgG to congopain were observed in the two trypanotolerant breeds, whereas the three susceptible breeds had lower levels of these antibodies. Crosses between N'Dama and Boran cattle, which exhibit an intermediate susceptibility, had intermediate levels of antibodies. Thus, the results from experimental infections confirmed our initial observations. However, under natural tsetse challenge, repeated infections and trypanocidal treatments in Zebu cattle stimulated as high anti‐congopain antibody levels as in non‐treated trypanotolerant taurine cattle.
Salivary gland material from the sand fly Lutzomyia longipalpis has an inhibitory effect on macrophage function in vitro
Authors: THEODOS CYNTHIA M. , TITUS RICHARD G. 
Published: October 2007

SummaryPrevious work from our laboratory demonstrated that the infectivity of the protozoan parasite Leishmania major was enhanced in mice if the infecting inoculum contained salivary gland lysates from the sand fly vector Lutzomyia longipalpis. The present study was designed to address the hypothesis that sand fly salivary gland material may function by inhibiting the host immune response. Results indicated that sand fly saliva inhibited the ability of macrophages to present leishmanial antigens to parasite‐specific T cells.
Mechanisms of eosinophilia in Toxocara canis infected mice: In vitro production of interleukin 5 by lung cells of both normal and congenitally athymic nude mice
Authors: TAKAMOTO MASAYA , SUGANE KAZUO 
Published: October 2007

SummaryMechanisms of eosinophilia were compared between in vitro bone marrow cell cultures of congenitally athymic (nu/nu) mice and their heterozygous littermates (nu/+). Cultures of 5 × 104bone marrow cells using interleukin 3 (IL‐3), IL‐5 and granulocyte‐macrophage colony‐stimulating factor showed that nu/nu and nu/+ mice mimicked each other in eosinophil production both before and after infection with Toxocara canis. Eosinophil differentiating activity (EDA) was detected in media conditioned by spleen cells and lungs of T. canis infected nu/+ mice, although nu/nu mice showed EDA only in lung‐conditioned medium. EDA, detected both in infected nu/nu and nu/+ mice, was inhibited by an anti‐IL‐5 monoclonal antibody. These results indicate that IL‐5 may be produced by lung cells of both nu/nu and nu/+ mice as well as by spleen cells of nu/+ mice infected with T. canis, which is the reason why nu/nu mice infected with T. canis exhibit blood eosinophilia.
Praziquantel‐induced exposure of Schistosoma mansoni alkaline phosphatase: drug‐antibody synergy which acts preferentially against female worms
Authors: FALLON P. G. , SMITH P. , NICHOLLS T. , MODHA J. , DOENHOFF M. J. 
Published: October 2007

SUMMARYThe efficacy of praziquantel‐treatment of murine Schistosoma mansoni‐infections can be enhanced by concurrent administration of rabbit anti‐sera with specificity for parasite antigens. Monospecific rabbit serum raised against S. mansoni worm alkaline phosphatase, that was reactive with the enzyme on the drug‐treated female surface, was found to significantly and preferentially increase the mortality of female worms by PZQ. Immunoglobulins purified from the anti‐alkaline phosphatase antiserum inhibited 54% of schistosome alkaline phosphatase enzymatic activity on the surface of praziquantel‐treated worms. We propose that synergistic antibody‐mediated death of drug‐damaged worms is a consequence of the inhibition of drug‐exposed alkaline phosphatase on the female worm surface by passively transferred antibody.
Goblet cell mucins of four genera of the subfamily Cricetinae with reference to the protective activity against Strongyloides venezuelensis
Authors: SHI B.‐B. , ISHIKAWA N. , ITOH H. , IDE H. , TSUCHIYA K. , HORII Y. , UCHIYAMA F. , NAWA Y. 
Published: October 2007

SUMMARYGoblet and mast cell responses in the jejunum of four genera, Mesocricetus auratus (Syrian hamster), Phodopus campbelli, Cricetulus griseus (Chinese hamster), and Tscherskia triton, belonging to the subfamily Cricetinae, were examined after infection with Strongyloides venezuelensis. Parasite eggs became detectable in faeces of all four genera on Day 7. Faecal egg count peaked around Day 8 in C. griseus and T. triton and around Day 14 in M. auratus and P. campbelli. In M. auratus and P. campbelli, faecal egg production persisted over 40 days, whereas that in C. griseus and T. triton rapidly terminated within 14 days. In all four genera examined, goblet cell hyperplasia and mastocytosis were observed at the time of expulsion of S. venezuelensis. However, in the comparative study of all four genera, neither the degree of goblet or mast cell hyperplasia nor the phenotype of mast cells correlated to the rapidity of the expulsion of S. venezuelensis. On the other hand, the rapidity of expulsion closely correlated with the degree of sulphation of goblet cell mucins because two genera, C. griseus and T. triton, having highly sulphated goblet cell mucins showed faster expulsion of S. venezuelensis than the other two genera, P. campbelli and M. auratus, having less sulphated mucins. These results suggest that physicochemical nature of mucins is critical for the expulsion of S. venezuelensis from the subfamily Cricetinae.
The role of adult worms in suppressing functional protective immunity toHeligmosomoides polygyrus bakerichallenge infections
Authors: PLEASS R. J. , BIANCO A. E. 
Published: October 2007

SUMMARYAdultHeligmosomoides polygyrus bakeri, radiolabelled with [35S]‐methionine were successfully transferred to naive NIH mice by oral gavage. Adult worms and radio‐label could be detected up to 45 days post‐infection. Adult worms gavaged into immune NIH mice, immunized with a drug abbreviated larval infection, were rejected within 45 days. These adult worms were unable to ablate the development of a functional protective response to a larval challenge infection in the NIH strain. In fact 50 adult worms were sufficient to significantly immunize NIH mice against a larval challenge infection. However, adult worms were able to suppress the development of a functional protective response in an outbred CFLP strain. Although a protective immune response could not be elicited to a challenge infection in CBA mice, the presence of gavaged adult worms was shown to increase the susceptibility of mice to a challenge infection. For all mouse strains, no significant difference in levels of L4 antigen‐specific serum IgG, IgG1, IgG2a, and IgA existed between immune mice and groups of mice immunosuppressed by adult worms. Levels of L4 antigen‐specific serum IgG1 were significantly lower in the poorly immunizable CBA strain compared to CFLP and NIH strains. No correlation was found across mouse strains between the intensity of the antibody response and the mean worm burdens per animal group. In addition, no correlation was found between levels of L4 antigen‐specific antibody within each mouse and the loss of worms by individual mice.