Spleen Weight as a Measure of Marrow Cell Growth in Irradiated Mice.

SummaryC57BL, C3H, C57BL/6, and DBA/2 parental marrow cells were injected at varying doses into lethally irradiated BC3F1 and B6D2F1 mice. Spleen weight in recipients was compared to spleen colony formation and Fe59 uptake. Results showed that increased spleen weight was proportional to formation of increased numbers of splenic nodules and percentage of Fe59 uptake. Data suggest that spleen weight, spleen colony formation, and Fe59 uptake are equally suitable assays, within appropriate limits, for studies on proliferation of marrow cell transplants in irradiated mice. Spleen weight is a useful index of growth for doses of transplanted marrow cells which promote recovery of hematopoietic injury in lethally irradiated mice.