B-CLL CELLS WITH UNUSUAL PROPERTIES

In studies concerning the interaction of B-CLL cells and Epstein-Barr virus (EBV), we encountered one patient whose cells had several unusua l properties, In addition to the B-cell markers, the CLL cells express ed the exclusive T-cell markers CD3 and CD8 and carried a translocatio n t(18,22)(q21;q11), involving the bcl-2 and Ig lambda loci. The patie nt represents the 4th reported CLL case with this translocation. The C LL cells could be infected and immortalized by the indigenous and by t he prototype B958 virus in vitro. The T-cell markers were not detectab le on the established lines. In all experiments the immortalized lines originated from the CLL cells, Their preferential emergence over viru s-infected normal B cells may be coupled to the high expression of the bcl-2 gene due to the translocation. In spite of the sensitivity of C LL cells to EBV infection in vitro, no EBNA-positive cells were detect ed in the ex vivo population. In vitro, we could generate cytotoxic fu nction in T-lymphocyte cultures which acted on autologous EBV-infected CLL cells. Therefore we assume that if such cells emerged in vivo the y were eliminated by the T-cell response. (C) 1997 Wiley-Liss, Inc.