Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 4 de 4
Filter
Add more filters










Database
Language
Publication year range
1.
Clin Vaccine Immunol ; 15(4): 659-67, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18305105

ABSTRACT

Infection of cattle with Neospora caninum protozoa, the causative agent of bovine protozoal abortion, results in robust cellular and humoral immune responses, particularly CD4(+) T-lymphocyte activation and gamma interferon (IFN-gamma) secretion. In the present study, N. caninum SRS2 (NcSRS2) T-lymphocyte-epitope-bearing subunits were incorporated into DNA and peptide preparations to assess CD4(+) cell proliferation and IFN-gamma T-lymphocyte-secretion immune responses in cattle with predetermined major histocompatibility complex (MHC) genotypes. In order to optimize dendritic-cell processing, NcSRS2 DNA vaccine was delivered with granulocyte macrophage-colony-stimulating factor and Flt3 ligand adjuvant. The synthesized NcSRS2 peptides were coupled with a palmitic acid molecule (lipopeptide) and delivered with Freund's adjuvant. Cattle vaccinated with NcSRS2 DNA vaccine alone did not induce T-lymphocyte activation or IFN-gamma secretion, whereas subsequent booster inoculation with NcSRS2-lipopeptides induced robust NcSRS2-specific immune responses. Compared to the response in control animals, NcSRS2-lipopeptide-immunized cattle had significantly increased NcSRS2-specific T-lymphocyte proliferation, numbers of IFN-gamma-secreting peripheral blood mononuclear cells, and immunoglobulin G1 (IgG1) and IgG2a antibody levels. The findings show that N. caninum NcSRS2 subunits bearing T-lymphocyte epitopes induced cell-mediated immune responses similar to the protective immune responses previously described against live parasite infection, namely T-lymphocyte activation and IFN-gamma secretion. The findings support the investigation of NcSRS2 immunogens for protection against N. caninum-induced fetal infection and abortion in cattle.


Subject(s)
Antigens, Protozoan/immunology , Antigens, Surface/immunology , Cattle Diseases/immunology , Coccidiosis/veterinary , Neospora/immunology , Protozoan Proteins/immunology , Protozoan Vaccines/immunology , Vaccines, DNA/immunology , Animals , Antibodies, Protozoan/immunology , Antigens, Protozoan/biosynthesis , Antigens, Protozoan/genetics , Antigens, Surface/biosynthesis , Antigens, Surface/genetics , COS Cells , Cattle , Cattle Diseases/parasitology , Cattle Diseases/therapy , Chlorocebus aethiops , Coccidiosis/immunology , Coccidiosis/parasitology , Coccidiosis/therapy , Dendritic Cells/immunology , Female , Interferon-gamma/immunology , Lipoproteins/immunology , Male , Neospora/isolation & purification , Protozoan Proteins/biosynthesis , Protozoan Proteins/genetics , Protozoan Vaccines/pharmacology , T-Lymphocytes/immunology , Vaccines, DNA/pharmacology
2.
Vaccine ; 26 Suppl 6: G29-33, 2008 Dec 19.
Article in English | MEDLINE | ID: mdl-19178890

ABSTRACT

Susceptible dairy cattle were immunized with attenuated, live calf-derived, in vitro-cultured or biologically cloned Babesia bovis, with non-viable exoantigens, or with recombinant rhoptry-associated protein 1 (rRAP1). Antibody response assessed by the indirect fluorescent assay (IFA) and by the growth inhibition activity in vitro showed that seroconversion correlated with neutralization activity in vitro in all immunized groups, but not with protective immunity in vivo. The protective responses elicited by immunization with completely avirulent biologically cloned live parasites, or by the exoantigens were sufficient for highly susceptible dairy cattle, in which prime immunization with blood-derived attenuated parasites cause clinical babesiosis. Upon challenge with virulent live parasites all immunized calves were solidly protected, but only partial protective immunity was acquired by rRAP1 immunization.


Subject(s)
Babesia bovis/immunology , Babesiosis/prevention & control , Cattle Diseases/prevention & control , Protozoan Proteins/administration & dosage , Protozoan Vaccines/administration & dosage , Vaccines, Attenuated/administration & dosage , Animals , Antibodies, Protozoan/blood , Antigens, Protozoan/administration & dosage , Antigens, Protozoan/immunology , Babesia bovis/pathogenicity , Babesiosis/immunology , Babesiosis/parasitology , Cattle , Cattle Diseases/immunology , Cattle Diseases/parasitology , Dairying , Protozoan Proteins/genetics , Protozoan Proteins/immunology , Protozoan Vaccines/immunology , Recombinant Proteins/administration & dosage , Recombinant Proteins/genetics , Recombinant Proteins/immunology , Treatment Outcome , Vaccination/veterinary , Vaccines, Attenuated/immunology
3.
Exp Appl Acarol ; 29(1-2): 141-9, 2003.
Article in English | MEDLINE | ID: mdl-14580066

ABSTRACT

Friesian cattle were immunized with two inoculations of anti-tick Bm86 (Tick-GARD) vaccine and were challenged 30 or 90 d later with Boophilus annulatus larvae derived from 1.2 g of eggs. No nymphs or adult ticks were found on the immunized cattle during four weeks after challenge. Repeated infestations (2 to 4) with larvae on three other calves during a period of 160 and 390 d after the immunization did not result in development of nymphal and adult stages. In control, non-immunized cattle infested with corresponding batches of larvae 1380 to 4653 replete adult female ticks were collected. Larvae issued from Babesia bovis-infected female ticks transmitted the infection to Bm86-immunized cattle, but the progeny of B. bigemina-infected females did not. Since B. bigemina is transmitted exclusively by nymphal stages of Bo. annulatus these results support the observation that immunity induced by Bm86 affects the larval stage of this tick.


Subject(s)
Cattle Diseases/prevention & control , Immunization/veterinary , Ixodidae/immunology , Membrane Glycoproteins/immunology , Recombinant Proteins , Tick Infestations/immunology , Tick Infestations/veterinary , Vaccines/immunology , Animals , Babesia bovis/immunology , Babesiosis/immunology , Babesiosis/prevention & control , Babesiosis/transmission , Cattle , Cattle Diseases/immunology , Cattle Diseases/parasitology , Female , Ixodidae/parasitology , Tick Infestations/prevention & control , Tick-Borne Diseases/immunology , Tick-Borne Diseases/prevention & control , Tick-Borne Diseases/transmission , Vaccines/therapeutic use
4.
Vet Parasitol ; 106(1): 35-43, 2002 May 30.
Article in English | MEDLINE | ID: mdl-11992709

ABSTRACT

Neospora caninum is a coccidian parasite identified as a major cause of abortion in cattle. A combined infection of N. caninum with another taxonomically related parasite of cattle, Besnoitia besnoiti can occur in geographical areas endemic for both species. Both infections are routinely diagnosed serologically, and incorrect diagnosis could occur if immunological cross-reactivity exists between the two parasites. To investigate the possible degree of cross-reactivity, we compared results obtained with two serological techniques, immunofluorescent antibody test (IFA), and Western blot analysis on known positive and negative sera. The test sera were derived from naturally infected cattle and from experimentally infected Mongolian gerbils. In IFA of bovine sera, no cross-reactvity was detected at the commonly used serum dilution cutoffs of 1:200 for N. caninum and 1:256 for B. besnoiti. However, at 1:64 dilution of both cattle and gerbil sera, anti-N. caninum sera reacted with B. besnoiti antigen in some individual samples. Anti-B. besnoiti serum did not react with N. caninum antigen at any dilution. This low level one directional cross-reactivity was confirmed by Western blot analysis. B. besnoiti antigen showed two immunoreactive bands when probed with anti-N. caninum serum, while no bands appeared when N. caninum antigen was probed with B. besnoiti antiserum. Immunization and challenge experiments in the highly susceptible Mongolian gerbil (Meriones unguiculatus) showed essentially no cross-protection between N. caninum and B. besnoiti.


Subject(s)
Cattle Diseases/immunology , Coccidiosis/veterinary , Neospora/immunology , Sarcocystidae/immunology , Animals , Antibodies, Protozoan/blood , Blotting, Western , Cattle , Cattle Diseases/diagnosis , Cattle Diseases/parasitology , Coccidiosis/diagnosis , Coccidiosis/immunology , Coccidiosis/parasitology , Female , Fluorescent Antibody Technique, Direct , Gerbillinae , Immunization , Male
SELECTION OF CITATIONS
SEARCH DETAIL
...