Host-determined differences in expression of surface marker characteristics on human and simian lymphoblastoid cell lines transformed by Epstein-Barr virus.

In an attempt to account for differences in the biologic behavior of Epstein-Barr virus in different primate species, we studied lymphocyte surface markers on primary and transformed cells. Among primary leukocytes, the distribution of cells with characteristics of bone-marrow-derived cells (B cells) was similar in humans, wooly monkeys, and cotton-top marmosets. However, after transformation by Epstein-Barr virus, cells from each species were characterically different. Transformed human umbilical cord cells expressed the complement receptor; monkey cells exhibited both this receptor and the receptor for IgG Fc (EA7S); and marmoset cells did not have either surface marker. We measured the transformation efficiency of human and marmoset leukocyte subpopulations enriched or depeleted in cells with the complement receptor. In both species the highest efficiencies of transformation were found in populations with the greatest numbers of cells with the receptor. The data therefore suggest that, in all species, a cell with the complement receptor is susceptible to transformation but that this receptor is not expressed on transformed marmoset cells. Thus, in Epstein-Barr virus-induced transformation it is necessary to distinguish between transformation of growth properties (immortalization) and transformation of cell surface properties.