CHARACTERIZATION OF DIFFERENTIATION ANTIGENS EXPRESSED IN BOVINE LYMPHOSARCOMAS

To characterize the cell-surface antigens expressed in tumour cells de rived from bovine leukosis and to determine their cell lineages, the i mmunophenotypes of the tumour cells from 13 bovine lymphosarcomas were examined with 13 monoclonal antibodies (mAbs). Of 13 cattle with lymp hosarcomas, four were identified clinically as having the thymic-type sporadic bovine leukosis (SBL) and one as having the skin-type; two ha d enzootic bovine leukosis (EEL) and six were untypable. Flow cytometr ic analysis revealed that the tumour cells from nine cases were of T-c ell lineage (BoCD(5+) BoCD(2+) or BoCD(2-)) and two were of B-cell lin eage (MHC-II+, BoCD5(+), IgM(+)); there were two bovine leukaemia viru s-infected cattle (EBL). T-cell rumours appeared to originate from imm ature (BoCD4(-), BoCD8(-)) T cells, but there was no significant relat ionship between clinical type (EEL, calf-, skin- and thymic-type) and tumour-cell immunophenotype. (C) 1997 W.B. Saunders Company Limited.