Studies of human bone marrow stromal cells in the aged Part 1. Influence of aging on composition, growing dynamics and cytokine production in human bone marrow stromal cells

Bone marrow stromal cells (BMSC) play essential roles in hemopoiesis. In the present study, bone marrow specimens obtained from 23 normal volunteers were cultured with a modified version of Dexter's long term bone marrow culture system to investigate the influences of aging on human BMSC. The composition of BMSC was analyzed by immunofluorescence. The percentage of monocyte/macrophages, adipocytes and T-cells were significantly increased in the aged. BMSC from the aged proliferated more rapidly than those from the young during the first week of culture in the growing dynamics study. Cytokine concentration in the conditioned medium was also measured in terms of BMSC function by radioimmunoasssay or enzyme-linked immunosorbent assay. The concentration of macrophage colony stimulating factor (M-CSF) on day 21 increased in the culture from the young, while interleukin-6(IL-6) concentration was higher on day 7 in the culture from the aged. These findings show no evidnece of BMSC defects in the aged. They show evidnece suggesting advanced function.