Developmental potential of hematopoietic stem cells determined using
retrovirally marked allophenic marrow
G Van Zant, JJ Chen and K Scott-Micus
Department of Cell Biology and Anatomy, Texas Tech University Health
Sciences Center, Lubbock 79430.
Genetic markers of two general types have been used to assess the number of
simultaneously productive stem cells in vivo, retrovirus markers and enzyme
or hemoglobin variants. Use of the two techniques has led to different
conclusions regarding stem-cell population organization, kinetics, and
usage. To better understand this discrepancy, we have combined the two
methods by retrovirally marking and transplanting stem cell populations of
allophenic mice in which all tissues, including the hematopoietic system,
are chimeric. Hematopoietic and lymphoid tissues of engrafted recipients
were analyzed by Southern blotting to determine the number and extent of
participation of individually marked stem cells. Genotypic chimerism of the
same tissues was determined by quantitating electrophoretic variants of
glucose phosphate isomerase. This procedure permitted the genotypic
identification of individual stem-cell clones. The results demonstrate the
participation of few pluripotent stem cells in the repopulation and
maintenance of engrafted hematopoietic and lymphoid tissues. Furthermore,
stem cells used during the period of early engraftment tended to be of one
genotype (DBA/2), whereas stem cells used for long-term maintenance tended
to be of the other, coexistent genotype (C57BL/6). We propose that this
genotypic specificity reflects functional differences in stem-cell
subpopulations and their relative prevalence in different mouse strains
suggests a genetic component in the organization and usage of stem cells.
Volume 77,
Issue 4,
pp. 756-763,
02/15/1991
Copyright © 1991 by The American Society of Hematology
