New leukemia risk factors research from Sun Yat-Sen University outlined

04-04-2007

New research, "Predominant immature CD8alpha+ dendritic cells prevent graft-vs.-host disease but do not increase the risk of leukemia recurrence," is the subject of a report. "Graft-vs.-host disease (GVHD) remains the major limitation of allogeneic bone marrow transplantation (BMT) and stem cell transplantation, and leukemia recurrence is another important complication in leukemia treatment. Immature CD8alpha+ dendritic cells (DC) have good potential in GVHD treatment and immunological tolerance studies," researchers in People's Republic of China report.

"To find a new way to prevent GVHD, not increasing the risk of leukemia recurrence, in this study, predominant CD8alpha+ immature DC were induced from murine bone marrow (BM) cells by 5 ng/mL granulocyte-macrophage colony stimulating factor (GM-CSF) plus 20-ng/mL interleukin (IL)-4, 100-ng/mL stem cell factor (SCF) and 25-ng/mL Flt3L, and 97.09 of prepared DC were CD8alpha+ on day 3. These DC were identified as morphologically and phenotypically immature CD8alpha+ DC. The suppressive function was observed in vitro, and then in vivo on allo-BMT leukemia model. The prepared predominant immature CD8alpha+ DC were weak syngeneic lymphocyte stimulators and could suppress mixed leukocyte reaction in vitro. In vivo, they prevented the pathological changes of GVHD and prolonged the surviving time of allo-BMT leukemia mice. The effect showed a dose-effect relationship. 86.7% of allo-BMT plus 1 million predominant CD8alpha+ DC leukemia mice reached long-term survival. Although predominant immature CD8alpha+ DC had the function of GVHD suppression, they did not increase leukemia recurrence," wrote L. Xu and colleagues, Sun Yat-Sen University.

The researchers concluded: "The method and findings may have important potency for GVHD treatment in clinical application."

Xu and colleagues published their study in European Journal of Haematology (Predominant immature CD8alpha+ dendritic cells prevent graft-vs.-host disease but do not increase the risk of leukemia recurrence. European Journal of Haematology, 2007;78(3):235-45).

For additional information, contact L. Xu, Center for Stem Cell Biology and Tissue Engineering, Sun Yat-sen University, Guangdong Province, China.

Publisher contact information for the European Journal of Haematology is: Blackwell Munksgaard, 35 Norre Sogade, PO Box 2148, DK-1016 Copenhagen, Denmark.

This article was prepared by Hematology Week editors from staff and other reports. Copyright 2007, Hematology Week via NewsRx.com.