Reticulocytes II: Reexamination of the in vivo survival of stress
reticulocytes
NA Noble, QP Xu and LL Hoge
Department of Medicine, University of Utah School of Medicine, Salt Lake
City 84132.
Very young reticulocytes are released into the circulation in response to
the stress of anemia. These stress reticulocytes have shortened in vivo
survival when transfused into normal recipients, and are generally
considered to be abnormal because they have skipped a terminal cell
division. We reevaluated one aspect of their abnormality: that of in vivo
survival. Using methodology that accounted for all cells transfused, in
vivo survival of both normal and stress reticulocytes was investigated in
both normal and anemic recipients. The experiments demonstrate that: (1)
survival of reticulocytes is normal only when normal reticulocytes are
injected into nonanemic animals; (2) intrinsic properties of stress
reticulocytes lead to their immediate removal from the circulation by
normal recipients to a significantly greater extent than by anemic
recipients; and (3) both stress and normal reticulocytes are removed at an
accelerated rate over time by anemic recipients. Taken together, the data
indicate that in the course of becoming anemic, an adaptation occurs that
allows cells produced during anemia to circulate considerably longer in
anemic animals than they could in normal nonanemic animals. Other studies
disclosed that increased reticulocyte survival in anemic animals could not
be attributed to reticuloendothelial overload, but is induced by adaptation
of the spleen, decreasing its removal of stress reticulocytes.
Volume 75,
Issue 9,
pp. 1877-1882,
05/01/1990
Copyright © 1990 by The American Society of Hematology
