Expression And Their Significance Of TRAIL And DR5 In Aplastic Anemia

Objective Aplastic anemia (AA) is a heterogeneity disease,caused the failure to the bone and in hematopoietic function by a variety of etiology, caused pancytopenia in clinical.The pathogenesis of AA is complex,concerning hematopoietic stem cell damage, dysimmunity, hemopoietic microenvironment change. The main pathogenesis is dysimmunity, especially the cells immune function exception.Haematogenesis negative regulatory factors secreted by T lymphocyte induced the apoptosis of CD34+ cells in AA patients'bone marrow increase by Fas/FasL system,and resulted in the quantity of hemopoietic stem cell decrease. However,when the way of Fas was blocked,there was still the apoptosis of bone marrow hematopoietic stem cell.It prompts activated T lymphocyte could induce the apoptosis of hematopoietic stem cell by other way except the way of Fas. In recent years,the researches showed there was a new apoptosis molecule on T lymphocyte.This new apoptosis molecule was named TNF related apoptosis-inducing ligand(TRAIL). TRAIL could combine with its death receptor to induce the apoptosis of tumor cell,transformant and virus infected cell, but it does not induce the apoptosis of most of normal cells.Therefore,there will be wide application in the future in the cure of many solid tumor.Whether this apoptosis way could also induce the apoptosis of hemopoietic stem cell is worth research and discuss.To detect the expression of TNF related apoptosis-inducing ligand(TRAIL) and its death receptor(DR5mRNA) on the bone marrow mononuclear cells in aplastic anemia patients, and approach their effect on the apoptosis of haemopoietic stem cell in aplastic anemia.Methods Flow cytometry and reverse transcriptase polymerase chain reaction (RT-PCR) were used to detect the expression of TRAIL and DR5mRNA on BMMNC in 12 aplastic anemia patients(AA group), BMMNC in 11 AA patients after cure with complete remission (CR group)and BMMNC in 12 normal persons (control group).Results①TRAIL and DR5mRNA were expressed in AA group, CR group and control group.②The level of TRAIL in AA group was (5.76±3.28)%,the level of DR5mRNA in AA group was (0.1153±0.02), but the level of TRAIL in CR group was(2.44±2.00)%,the level of DR5mRNA in CR group was (0.1018±0.01), and the level of TRAIL in control group was (3.24±2.18)%, the level of DR5mRNA in control group was (0.1026±0.01). The level of TRAIL and DR5mRNA expression in AA group was higher than that in CR group and control group(P<0.05).③There is no difference in statistics between cure group and normal group(P>0.05).Conclusion The expressions of TRAIL and DR5mRNA on BMMNC in AA patients is the highest.It prompts the apoptosis induced by TRAIL and DR5 may play an important role in the pathogenesis of aplastic anemia.