Distribution of granulocytopoietic committed stem cells in mice with tumor induced neutrophilia.

The skeletal distribution of granulocytopoietic committed stem cells (CFUc) was studied in mice bearing a granulocytosis inducing tumor. The total number of CFUc per mouse was estimated and compared with control mice. In both the axial skeleton (vertebrae, skull, tail) and new areas of marrow development in the peripheral skeleton (radii and ulnae), there was an increased incidence of CFUc, while central appendicular long bones (humeri, femora and tibias) CFUc were unchanged. The study indicated that the total number of CFUc in tumor bearing mice increased, additional data supporting the previous observation and the granulocytosis in this animal model is due to an increase in cell production. The study also indicated that inferences about total CFUc numbers of granulocyte production based on CFUc assay from a single long bone should be interpreted with caution.