Thalassemic serum panel reaction antibody inhibits proliferation and differentiation of cord blood hematopoetic stem cells in children patients

Jianpei FANG; Wenjun WENG; Yanfeng WU; Xingge YANG; Luhong XU; Honggui XU; Jing WEI

ABSTRACT

BACKGROUND:

Panel reaction antibody (PRA) plays an important role in rejection of recipients undergoing solid organ transplantation, which has a positive effect on nonfunction of implant.

OBJECTIVE:

To evaluate the effect of thalassemic serum-specific PRA on the proliferation and differentiation of umbilical cord blood hernatopoetic stem/progenitor cells (HSC/HPCs) in children patients with thalassemia. DESIGN, TIME AND

SETTING:

The in vitro cytology experiment was performed at the Experimental Research Center, Second Affiliated Hospital, Zhongshan University from January 2006 to August 2007. MATERIALS Five samples of umbilical cord blood from healthy full-term birth puerperants (each 80 100 mL) were used in this study. PRA serum samples of children patients with thalassemia after repetitive blood transfusion, five samples of AB blood grouping serum, and six samples of positive anticoagulation vein blood (10 mL) were used in the study.

METHODS:

Mononuclear cells were harvested from umbilical cord blood by Ficoll-Hypaque gradient centrifugation. 1 × 105 rnononuclear cells from umbilical cord blood were incubated with different levels of experimental or AB control serum (0, 50, 100 μ L) from healthy children. The mixture mentioned above was incubated with rabbit complement for semisolid colony culture.MAIN OUTCOME

MEASURES:

Colony-forming units (CFU) were counted and observed after 7 days and 14 days of culture under an inverted microscope.

RESULTS:

After incubation with HSC/HPCs PRA serum, total number of CFUs and varied CFUs decreased to different extents, of which the total number of CFUs and CFU- granulocyte-rnacrophages (CFU-GM) had significant differences (P < 0.01). Moreover, there were negative correlations between different levels of serum PRA and the followings number of total colonies, CFU- GM, CFU- granulocyte-erythrocyte-monocyte-megakaryocytes, CFU-erythroids, burst forming unit-megakaryocytes, and CFU-megakaryocytes (P < 0.05).

CONCLUSION:

The thalassemic serum PRA has an apparent inhibitory effect on the proliferation and differentiation of cord blood HSC/HPCs in vitro, an effect that may be pronounced with increasing serum PRA.