The Journal of Immunology, Vol 147, Issue 10 3336-3341, Copyright © 1991 by American Association of Immunologists

ARTICLES

Differentiation in mature T lymphoid leukemia cells is unstable and reversible to myeloid cells, without the involvement of a common stem cell

F Griesinger, B Jansen and JH Kersey
Department of Laboratory Medicine/Pathology, University of Minnesota, Minneapolis 55455.

Mechanisms for the unstable and reversible differentiation of a mature CD3+ CD7+TCR-alpha/beta+ T lymphoid leukemia into the myeloid lineage were investigated. Inasmuch as productive rearrangement of the TCR- alpha is a late determinant of T cell differentiation, the TCR-alpha rearrangement was sequenced to determine the state of differentiation of the leukemic multipotent cell. An identical productive rearrangement of J alpha C to a novel V alpha region was found in the myeloid and T lymphoid leukemic cells. Thus, a "terminally" differentiated T lymphoid leukemic cell after productively rearranging TCR-alpha and -beta continues to display potential for multilineage differentiation. Therefore, multilineage potential is due to an unstable and reversible differentiation in a mature T lymphocyte as opposed to differentiation of an uncommitted common T and myeloid precursor cell.