A cell surface antigen associated with Theileria parva lawrencei-infected bovine lymphoid cells.

Attempts to produce monoclonal antibodies specific for a parasite-encoded or induced antigen on the surface of Theileria parva lawrencei-transformed bovine lymphocytes resulted in the identification of the monoclonal antibody J7. This antibody recognizes a membrane glycoprotein on some T.p. lawrencei-infected bovine lymphoid cells but not on any uninfected bovine lymphoid cells. Inoculation of allogeneic recipient cattle with T.p. lawrencei-transformed cells bearing the J7 determinant resulted in transfer of the parasite but not of the J7 epitope to the recipients' own cells. The presence of the J7 determinant could not be correlated with the parasite phenotype nor with the surface phenotype of the infected cells. It is therefore not known whether the J7 epitope is of parasite origin or whether it is a bovine differentiation antigen modified by the presence of the parasite.