Frequent exposure of mice to crude Brucella abortus proteins down-regulates immune response.
Mice repeatedly immunized via the intraperitoneal route with a Brucella abortus antigen lost their ability to develop a strong in vitro lymphoproliferative response. This result correlates with a decreased tendency of the lymphoid population to produce interferon-gamma when stimulated in culture with the immunizing antigen. With respect to the humoral response, as the number of immunizations increased, the animals produced more specific immunoglobulin M and immunoglobulin G1 antibodies. It is postulated that the long-term exposure of an animal to Brucella antigen changes the nature of the immune response from a T-cell-mediated response to a humoral response favouring the establishment of the disease.
Department of Microbiology, Faculty of Biological Sciences, Universidad de Concepción, PO Box 152-C, Concepción, Chile. aonate@udec.cl
A
A
Oñate
E
E
Andrews
A
A
Beltran
G
G
Eller
G
G
Schurig
H
H
Folch
D000818:Animals; D000942:Antigens, Bacterial / Q000008:administration & dosage / Q000276:immunology; D001426:Bacterial Proteins / Q000008:administration & dosage* / Q000276:immunology; D002003:Brucella abortus / Q000276:immunology* / Q000472:pathogenicity; D002006:Brucellosis / Q000276:immunology / Q000662:veterinary*; D004195:Disease Models, Animal; D015536:Down-Regulation; D005260:Female; D007107:Immune System / Q000276:immunology*; D007114:Immunization / Q000379:methods / Q000662:veterinary*; D007274:Injections, Intraperitoneal / Q000662:veterinary; D051379:Mice; D008807:Mice, Inbred BALB C
D000942:Antigens, Bacterial; D001426:Bacterial Proteins