Characterization of two newly established EBV-containing lymphoblastoid cell lines from patients with myeloid...

Two spontaneous outgrowing Epstein-Barr virus (EBV)-carrying lymphoblastoid cell lines (LCLs), CG2 and CG3, have been established from bone marrow cells of myeloid leukemia patients. CG2 was derived from a patient with chronic myelomonocytic leukemia (CMMoL) and who has a 45 XO karyotype. CG3 was derived from a patient with juvenile chronic myeloid leukemia (CML) and who carries a hypotetraploid karyotype, 91XXYY. Both CG2 and CG3 cells carry the same type of translocation; t(1;19)(q23;p13). Both cell lines are of an early B cell lineage as shown by their reactivities with monoclonal antibodies OKIa, B1, B2 and B4. The combination of horizontal discontinuous agarose slab gel and Southern hybridization results show CG2 and CG3 cells are of monoclonal origin and harbor episomal EBV genomes. Approximately 50 EBV genome equivalents were contained in CG2 and CG3 cells. Immunofluorescence studies demonstrate the expression of EBV-encoded antigen (EBNA) in almost all cells of these two lines. The expression of EA and VCA is only observed in a small percentage of cells and cannot be induced by treatment with TPA and SB. Therefore, CG2 and CG3 cells are probably nonproducer cell lines for EBV. The serum samples from both patients have been shown to contain elevated IgG antibody titers to EBV antigens. Both cells are found to be nontumorigenic in nude mice. These cells may provide an important tool in analyzing molecular epidemiological aspects of EBV infections in diseases such as CMMoL and juvenile CML.