Reduced Blood and Marrow Neutrophils and Granulocytic Colony-Forming Cells in Sl/Sl d Mice 1

Abstract

Summary

The Sl/Sl^d mouse has been shown to have anemia and reduced megakaryocytes, but neutrophil levels in blood and marrow have not been studied previously to our knowledge. It proved to be neutropenic with reduced neutrophils and neutrophil precursors in marrow. The concentration of marrow cells forming granulocytic colonies in semisolid media was normal in young mice, but the total number per humerus was reduced. In vitro growth appeared normal in both semisolid and liquid culture, and peritoneal cells produced colony-stimulating activity normally. These results are compatible with previous studies indicating the Sl/Sl^d defect lies in the hematopoietic microenvironment rather than being a primary cellular defect, and suggest feedout from the pluripotent stem cell compartment may be reduced.