OBJECTIVETo explore in vitro expansion of CD34+CD59+ cells from patients with PNH, and compare the capabilities of survival, proliferation and expansion between CD34+CD59+ cells from patients with PNH and CD34+ cells from normal control.

METHODSCD34+CD59+ cells from patients with PNH and CD34+ cells from normal control were selected from the bone marrow mononuclear cells by means of two-step sorting method with immunomagnetic microbead-flow cytometry, then underwent in vitro expansion for two weeks and semi-solid culture in vitro before and after expansion.

RESULTS(1) CD34+CD59+ cells from patients with PNH can be expanded effectively in vitro, and the biggest expansion of CD34+CD59+ cells was about 23.49 fold on the 7th day. (2) There were some similar characteristics between CD34+CD59+ cells from patients with PNH and CD34+ cells from normal control, such as: the best combination of hematopoietic factors for in vitro expansion was SCF+ IL-3 + IL-6 + FL + Tpo + Epo, and the seventh day was the most suitable in course of 4-14 days for in vitro expansion, and after in vitro expansion, the cells remained CD59 positive and strong capability of performing colony-forming. (3) CD34+ cells from normal control had better proliferation, expansion and stronger potential to survive than CD34+CD59+ cells from patients with PNH.

CONCLUSIONS(1) In vitro expansion of CD34+CD59+ cells from patients with PNH can be performed. The present study showed the possibility of performing ABMT or APBSCT clinically for patients with PNH. (2) There were some similar characteristics between CD34+CD59+ cells from patients with PNH and CD34+ cells from normal control, but the latter had better proliferation, expansion and stronger potential to survive than the former. CD34+CD59+ cells from patients with PNH were not completely normal cells.