The Study Of Correlation Between Tissue Factor Expression And Microvessel Density In Bone Marrow Of Acute Leukemia Patients

Objective Bone marrow of ninteen patients with newly diagnosed acute leukemia and twelve normal man were analyzed by flow-cytometry for tissue factor, microvessel density in marrow was evaluated using von Wille-brand factor as the endothelial marker to understand whether tissue factor expression may correlate with microvessel density in bone marrow in acute leukemia patientsMethods Ninteen patients with newly diagnosed acute leukemia and twelve normal man or ITP patients were enrolled. three of the patients had acute myeloid leukemia (AML)-MO , 2 had AML-M1, 3 had AML-M2, 3 had AML-M3, 3 had AML-M4, 2 had AML-M5, 3 had ALL . bone marrow aspirates and bone marrow biopsies were taken prior to chemotherapy treatment. The Microvessel density (MVD) was assessed based on the method as recommended: Slides were immuriostained with anti-VWF antibody, MVD is calculated as microvessel count within 1mm~2 of slides under high power magnificent,tissue factor expression was measured by flow cytometry (FCM) : Mono-nuclear cells were isolated from heparinized bone marrow over Ficoll-Isopaque, FITC-conjugated anti-TF were added , measured in 24 hours.Results The percentage of mononuclearcell in acute leukemia patients borrow which express tissue factor is 54±13%, while it was not detected in control group compare with the control group (9. 2±2.4/×400field) , microvessel density in borrow marrow of acute leukemia patient (20.8± 7.5/×400 field) is higher.. (p<0.05) .Tissue factor expression was positively correlated with MVD value (r=0.7601,p<0.01).Conclusions As most kinds of tumor, angiogenesis is common in acute leukemia. angiogenesis may play an important role in pathophysiology of acute leukemia. Tissue factor , which is expressed at a low level on the surface of some kinds cell usually , expressed at a high level on leukemia cells. Tissue factor expression was positively correlated with MVD value, it may priming the angiogenic switch to form new blood vessel as an factor which facilitate the formation of blood vessel. Anti-angiogenesis drugs which use tissue factor as target or to unite with chemotherapeutics may raise curative effect of acute leukemia.