[Research on expansion of CD34+ cells from umbilical cord blood using different cytokine groups in vitro].

OBJECTIVE: To investigate the expansion of the CD34+ cells of umbilical cord blood in vitro culture comprising different cytokines and the potential hematopoiesis function of the expanded CD34+ cells. METHOD: Expanding the purified CD34+ cells from the fresh umbilical cord blood for 6 days in vitro with the use of different combination of FL, SCF, TPO, IL-3 and IL-6. Getting one better combination by analyses of the results from flowcytometry, LTC-IC, and progenitor clonogenic assays. RESULTS: The numbers of CD34+ cells expanded by use of different combination of cytokines were 3.1-8.6 times as large as the numbers of ordinary ones, thus making 16 cases of insufficient CD34+ cells become able to satisfy the needs of the adults weighing 50 kg. No significant difference was observed between the function of the expanded cells and the original ones in hematopoiesis. Meanwhile, it was proved that TPO in combination with other cytokines could strengthen the expansion of CD34+ cells, but using TPO alone for long time culture would cause more CD34+ cells to be megalocaryocytes. CONCLUSION: The combination of FST36 cytokines can expand the CD34+ cells of the umbilical cord blood to meet the adults' needs in laboratory's methods.