Controlled Environment Culture of Bone Marrow Explants from Human Myelom&

After obtaining informed consent, biopsy specimens of bone were obtained from the posterior iliac crest of patients with myeloma or other neoplastic diseases with a Wester man Jenson needle. These biopsy specimens ranged from 0.3 to 0.6 cm long. The bone explants were cultured in 2 thin-film culture systems (7-9); (a) an automated unit capa ble of being programmed for proportional media exchange on cultures (this unit will be referred to as the 552 culture system) and (b) a modified Leighton tube equipped with a 10-mI capacity side arm that permitted the culture of a small piece of tissue with maintenance of proper fluid tissue ratio (this unit will be referred to as the AT culture system). For the AT system, the specimens were quickly and asept ically placed on the flat surface of the modified Leighton tubes. Ten ml of culture media were pipetted into the reser voir of the tubes, which were then closed by silicone rubber stoppers that contained glass tubing ports for gas ex change. The culture tubes were then attached to the tube rocking device and were individually gassed in an incubator at 37°. The tube platforms were automatically rocked with a traverse of 45° for 30 sec of each 3-mm cycle. Thus, the film of culture fluid over the explant was exchanged 20 times/hr with media from the reservoir. About a 0.5-mI aliquot of the culture media was aspirated dail@,pH measurements of the fluid served as a monitored function and thus indicated time for media renewal in the auxiliary reservoir. In experiments where specimens were cultured in the SS system, a bone explant was placed in a roller tube that contained 1.5 ml of culture media. The culture tube was connected to the feed and drain manifolds of the tray prior