RESUMEN
From circulating immune complexes (ICs) of BLV-infected cattle, an antigen preparation was produced that contained some virus-specific proteins and a tumour-associated antigen. Eleven hybridoma clones were produced that secreted monoclonal antibodies (MoAbs) to this tumour-associated antigen, and two of them, MoAbs 1B4 and 1E9, were used in further studies. Most antibodies were of IgG1 subclass and showed no cytotoxic activity towards lymphocytes of BLV-positive cattle or to certain tumour cells. The MoAbs 1B4 and 1E9 recognized an antigen of about 75 kD on the cell surface of bovine lymphosarcoma cells and circulating lymphocytes from BLV-infected cattle with persistent lymphocytosis. The results presented indicate that the circulating immune complexes from BLV-positive cattle contain a tumour-associated antigen that is expressed on tumour cells and on lymphocytes from cattle with persistent lymphocytosis.
Asunto(s)
Anticuerpos Monoclonales , Complejo Antígeno-Anticuerpo/sangre , Antígenos de Neoplasias/sangre , Leucosis Bovina Enzoótica/inmunología , Animales , Anticuerpos Monoclonales/biosíntesis , Antígenos de Neoplasias/aislamiento & purificación , Bovinos , Leucosis Bovina Enzoótica/etiología , Leucosis Bovina Enzoótica/virología , Femenino , Técnica del Anticuerpo Fluorescente Indirecta , Inmunohistoquímica , Virus de la Leucemia Bovina/inmunología , Linfocitos/inmunología , RatonesRESUMEN
Calves of two breeds--Brown Latvian and Black and White, were immunized against bovine leukemia virus with an immunogen produced from short-term cultured blood lymphocytes of BLV-positive Brown Latvian cows. The immunogen contained the viral proteins gp51 and p24 as well as some cellular proteins. As determined by bioassay in sheep, it did not contain infective bovine leukemia virus. The calves were challenged by BLV-producing lymphocytes 2 weeks after the immunization procedure. Effective protection against BLV infection was induced by the tested immunogen in all Brown Latvian calves for 6 months and in 70% of the Black and White calves.