CELL-FUNCTION STUDIES IN LONG-TERM BONE-MARROW CULTURE AFTER CELL CONCENTRATION AND CRYOPRESERVATION FOR AUTOLOGOUS TRANSPLANTATION

Autologous bone marrow transplantation (ABMT) is frequently used in the treatment of neoplastic diseases. It involves several manipulations in vitro that can damage the stem cells responsible for grafting. Long-term bone marrow cultures (LTBMC) reproduce the bone marrow microenvironment and support haematopoiesis in vitro for several weeks. This technique provides information on the extent of the injury of stem cells during manipulations of bone marrow cells in vitro. We studied the effect of the usual process of bone marrow cells in vitro in autologous transplantation: cell concentration and cell cryopreservation. 28 bone marrows from healthy donors and 45 from patients who had undergone ABMT were assayed in LTBMC. The cultures were initiated after manual or automatic buffy coat cell separation or after density gradient or automatic mononucleated cells suspension. Bone marrows were studied pre- and post-cryopreservation. The results show that several manipulations can disturb normal cell behaviour in LTBMC. Following automatic mononucleated cell separation and after thawing, the development of adherent cell layer in LTBMC is anomalous. These manipulations led to a delay in covering 50% of the flask surface, absence of adypocytes in adherent cell layer and absence of haemopoietic precursors in the supernatant at the 4(th) week of culture. The results suggest that LTBMC can be used for control of the manipulations in vitro related with ABMT.