Desoxyribonucleic acid synthesis by bone marrow cells in vitro

The incorporation of C¹⁴-formate into thymine is described as a method formeasuring desoxyribonucleic acid synthesis by bone marrow cells in vitro. Themethod is satisfactorily reproducible and permits measurement of DNA synthesis over short periods of time with small amounts of bone marrow.

Normal serum was found to be essential for rapid rates of DNA synthesis andcould not be replaced by supplemented media. The rate of DNA synthesis wasalmost constant during the first 4-6 hours of incubation, but fell off rapidlythereafter. The ability to promote DNA synthesis was found to differ from onenormal serum to another. The optimal pH for DNA synthesis was approximately7.8.

Because DNA synthesis is vitally concerned with cell duplication, measurementof the rate of its synthesis should be a valuable tool for measuring viability ofthose marrow cells young enough to proliferate.

Submitted on May 3, 1957 Accepted on July 23, 1957