THE DEVELOPMENT OF FIBROBLAST COLONIES IN MONOLAYER CULTURES OF GUINEA‐PIG BONE MARROW AND SPLEEN CELLS

TLDR

In guinea‑pig bone marrow and spleen monolayer cultures, fibroblast colonies appear between days 9–12. The number of colonies increases linearly with cell density, indicating clonal origin, with a colony‑forming cell concentration of ~10⁻⁵; bone marrow fibroblasts can spontaneously form bone in diffusion chambers, while spleen fibroblasts cannot, but both cell types can be induced to osteogenesis by transitional epithelium.

Abstract

ABSTRACT In monolayer cultures of guinea‐pig bone marrow and spleen the development of discrete fibroblast colonies takes place on days 9–12. The linear increase in the number of colonies with increasing numbers of explanted cells and the distribution of male and female cells in mixed cultures support the view that fibroblast colonies are clones. The concentration of colony‐forming cells in bone marrow and spleen is approximately 10 ‐5 . Bone marrow culture (but not spleen culture) fibroblasts are capable of spontaneous bone formation in diffusion chambers. Fibroblasts from both bone marrow and spleen cultures are inducible to osteogenesis in diffusion chambers in the presence of transitional epithelium.