Cytogenetic and immunologic identification of clonal expansion of stem
cells into T and B lymphocytes in one Atomic-bomb survivor
Y Kusunoki, Y Kodama, Y Hirai, S Kyoizumi, N Nakamura and M Akiyama
Department of Radiobiology, Radiation Effects Research Foundation,
Hiroshima, Japan.
Chromosome aberration frequency in peripheral blood lymphocytes is elevated
in radiation-exposed people, and identical karyotypic changes are not
infrequently encountered in one blood sample as well as in separate samples
from the same donor. Such clonal propagation originates either from a
single immature stem cell able to expand and differentiate into several
cell types or from a single mature lymphocyte able to expand after antigen
stimulation in vivo. In the present study, a total 71 T-lymphocyte and 58
B-lymphocyte colonies were established from one atomic-bomb survivor, who
showed a persistent clonal aberration t(4;6), t(5;13) in phytohemagglutinin
culture of peripheral lymphocytes. Nearly 10% of the colonies (6
T-lymphocyte and 7 B-lymphocyte colonies) showed the same chromosome
abnormality. Southern blot analyses of the T-cell-receptor or Ig
heavy-chain gene showed all different rearrangement patterns among T- or
B-lymphocyte colonies, respectively. Thus, the chromosome aberration
occurred in a precursor cell before differentiation into T and B lineages
and was not derived from monoclonal proliferation of mature T or B
lymphocytes in the periphery. To confirm the issue, cells from erythroid
burst-forming unit (BFU-E) colonies were examined by the
chromosome-painting method. Two translocations, one between chromosomes 5
and 13 and the other between chromosomes 4 and one of group C, perfectly
consistent with the t(4;6), t(5;13), were found in about 10% of the cells.
The results imply that a single stem cell of an adult is capable of
generating long- lived myeloid and lymphoid progeny amounting to several
percent of the total population of circulating lymphocytes and
hematopoietic progenitors.
Volume 86,
Issue 6,
pp. 2106-2112,
09/15/1995
Copyright © 1995 by The American Society of Hematology
