EX VIVO Expansion of CD34~+ Cells in Stemline II Hematopoietic Stem Cell Expansion Medium Generates a Large Population of Functional Early and Late Progenitor Cells

摘要

Hematopoietic stem cell replacement therapy is an area of research lacking an optimal culture system that allows for the ex vivo expansion of CD34+ cells for transplant. The necessity for expansion is due to the lack of sufficient material from umbilical cord blood (UCB), the preferred source of CD34~+ cells. The final composition of the expanded cells is also very important to a successful transplant. The material must contain both early and late progenitor cells to ensure the long-term engraftmentthat is required in patients with genetic disorders and those that have gone through high dose chemotherapy. Stemline II Hematopoietic Stem Cell Expansion Medium was developed to facilitate the development of this replacement therapy. Culturing CD34~+ cells in Stemline II consistently yields higher levels of expansion than seen with other commercially available serum-free media. Analysis of the expanded material for lineage indicating markers by flow cytometry demonstrates that the material contains therequired early and late progenitors. Furthermore, NOD/SCID studies confirm that the expanded cells are capable of long-term engraftment and are therefore functional. Together, this data supports the conclusion that culturing CD34~+ cells in Stemline IIHematopoietic Stem Cell Expansion Medium is a key step in developing the optimal culture system.