Effect of donor age on the growth in vitro of cells obtained from human trabecular bone.

The proliferation of human bone-derived cells (BDCs) was assessed in vitro, using [3H]thymidine incorporation and cell counting in a haemacytometer. The cells were cultured from human trabecular bone from 87 patients aged 2-88 years. The in vitro growth of these cells was unaffected by the chronological age of the donor. However, the cell number at confluence was shown to decrease with increasing donor age, this trend being most marked after 60 years of age. Other assays of the metabolic efficiency of the BDCs, namely, total protein, osteocalcin, and alkaline phosphatase synthesis, did not show any change with increasing donor age. These results suggest that while the ability of individual cells to divide and to perform specific synthetic activities is unimpaired with increasing age, other subtler changes may occur, leading to a decrease in the bone's osteogenic capacity.