BIOLOGY AND CLINICAL-APPLICATIONS OF LONG-TERM BONE-MARROW CULTURES

A number of clonogenic assays for short-term bone marrow culture is no w available for the quantitative analysis of the various hematopoietic progenitor cell classes. The short-term assays are not suitable to an alyse either stem cell self-renewal or interactions of hematopoietic p rogenitors with stromal cells, especially those requiring direct cell- to-cell or cell-to-matrix contact. The technique of long-term bone mar row culture (LTBMC) allows a sustained production of myeloid cells whe n marrow is placed in liquid culture at relatively high cell concentra tion, with appropriate supplements, temperature and feeding conditions . A peculiar feature of LTBMC is that the stromal cells promote self-r enewal as well as differentiation of the stem cells, without the need to add exogenous growth factors. The LTBMC system offers an approach a ble to investigate not only the proliferative and differentiative even ts but also sustained cell production and self-renewal of any clonogen ic cell types. In the last years, the technique of LTBMC has been incr easingly used by several groups to investigate hematopoietic regulatio n, stromal cell function and the interactions among stromal and hemato poietic cells. In the present report, the biology of LTBMC and their p ossible clinical applications will be reviewed.