Establishment Of Tissue Factor-positive Microparticles Detecting With Flow Cytometry And Its Clinical Significance In The Patients With Hematological Malignant Diseases

Objective:(1)To establish the method of tissue factor-positivemicroparticles(TF+MPs) detecting with flow cytometry （FCM）.(2)To illustrate thealteration and clinical significance of TF+MPs in the patients with thrombotic disease andacute promyelocytic leukemia (APL) complicated with blood coagulation disorder.(3)Todetermine the value of the TF+MPs and endothelial microparticles (EMPs) intransplantation-related complications during the allogeneic hematopoietic stem celltransplantation (allo-HSCT), which contribute to early discovery of diagnosis oftransplantation-associated thrombotic disease.Methods:(1)Venous blood was anticoagulated with sodium citrate (1:9) in themorning. The TF+MPs and EMPs were detected by FCM using phycoerythrin(PE)-conjugated monoclonal antibodies to CD142for tissue factor (TF) and PE-cogjugatedmonoclonal antibodies to CD62E for endothelial cells, respectively. Forward scatter wasset in scale using fluorescent microspheres of0.8μm. Standard fluorescent microbeads(0-0.8μm) in diameter were used to set the microparticles gate.(2)TF+MPs were detectedin20cases with thrombotic disease and25cases with APL (17cases complicated withovert disseminated intravascular coagulation (DIC)). The differences of TF+MPs in variousgroups were analyzed.(3)The91allo-HSCT patients were enrolled in this study.According to the occurrence of transplantion-associated complications, thesetransplantation patients were divided into four groups: thrombotic group (VOD n=5, TMAn=1), acute graft-versus-host disease (aGVHD) group (n=27), infection group (n=41) andnon-complication group (n=17). Alterations of serum concentration of TF+MPs and EMPswere analyzed by FCM during the process of conditioning treatment and the early stagepost transplantation. Retrospective analyses were performed for the microparticles and thecomplications. Results:(1)The level of TF+MPs(123.28±197.03/μL) in the patients with thromboticdisease was significantly higher than that in the control group（33.27±16.14/μL）(P<0.05).Simultaneously, The TF+MPs level（75.24±104.58/μL）was increased in the patient withAPL than that in the control group, especially in course before therapy (P<0.01), but therewas no difference between the patients with APL after therapy and the control group.Among these patients with APL, the level of TF+MPs in the18patients who arecomplicated with overt DIC was also different before and after treatment (P<0.05), but thelevel of TF+MPs in the other7APL patients was similar before and after treatment.(2)TF+MPs and EMPs levels of patients undergoing allo-HSCT were higher than those ofnormal controls before conditioning treatment (P<0.01), but the TF+MPs and EMPs levelsafter conditioning treatment did not significantly changed(P>0.05). During transplantation,patients with thrombotic complications showed higher TF+MPs and EMPs compared withthe complications of aGVHD group, infection group and non-complication group (P<0.05).TF+MPs and EMPs had increased tendency in patients of aGVHD, thrombosis andinfection, but no significant difference was observed in the patients with aGVHD andinfection (P>0.05).Conclusion:(1) The method of TF+MPs measurement by FCM is feasible. It is usefulfor the diagnosis of thrombotic disorder, and helpful for the prognosis of APL patients whoare complicated with overt DIC.(2)The increase in the TF+MPs and EMPs may be onespecific mark for transplantation-associated thrombotic complications. The extremeelevation of TF+MPs and EMPs facilitates the early diagnosis of thrombosis from othertransplantation-associated complications. Monitoring TF+MPs and EMPs levels contributesto early discovery of thrombotic complications.