Preparation And Targeting Study In Vitro, Imaging Study In Vivo Of P-selectin Antibody Loaded Targeted Ultrasound Contrast Agent

PART I PREPARATION AND TARGETING STUDYIN VITRO OF P-SELECTIN ANTIBODY LOADEDTARGETED ULTRASOUND CONTRAST AGENTObjective To prepare a kind of P-selectin antibody loaded targetedultrasound contrast agent, and to investigate its ability of targeting in vitro.Methods P-selectin antibody loaded targeted ultrasound contrastagent was prepared via an “biotin-avidin” bridge. Its basic property wasdetermined. Human umbilical vein endothelial cells (HUVECs) werestimulated to express P-selectin by applying different doses of recombinanthuman interleukin-4(rhIL-4) and histamine. The expression level ofP-selectin was detected by immunofluorescence technique, and exploredrhIL-4optimal stimulation dose. The experiment group was divided intothree groups, including targeted ultrasound contrast agent, isotype controlultrasound contrast agent and blank ultrasound contrast agent. Targetingabilities of three groups were observed by adhering to treated HUVECs and untreated HUVECs, respectively.Results P-selectin antibody loaded targeted ultrasound contrastagent was prepared successfully. The average diameter was(2.24±0.71)μm. The average Zeta potential was(-2.75±0.84) mV. The concentrationwas(3.0±0.3)×109／ml. The rate of antibody binding was as high as99.80％. RhIL-4and histamine could stimulate HUVECs to expressP-selectin, and optimal stimulation dose was obtained. Targetingexperiment showed that targeted ultrasound contrast agent could preferablyadhere to HUVECs stimulated by optimal dose of rhIL-4and histamine.Compared with other five groups, there were significant differences.Conclusions P-selectin antibody loaded targeted ultrasound contrastagent was prepared successfully via an “biotin-avidin” bridge. The targetedultrasound contrast agent could effectively adhere to HUVECs stimulatedby rhIL-4and histamine. PART Ⅱ ULTRASOUND MOLECULAR IMAGINGSTUDY IN VIVO OF P-SELECTIN ANTIBODY LOADEDTARGETED ULTRASOUND CONTRAST AGENTObjective To prepare a kind of P-selectin antibody loaded targetedultrasound contrast agent, and to research its ultrasound molecular imagingeffect of evaluating myocardial ischemia-reperfusion injury. Methods P-selectin antibody loaded targeted ultrasound contrastagent was prepared via an “biotin-avidin” bridge. Prepared the model ofmyocardial ischemia-reperfusion injury. Ten dogs with myocardialischemia-reperfusion were injected with P-selectin antibody loadedtargeted ultrasound contrast agent (MBp) and blank control ultrasoundcontrast agent (MBc) randomly (interval was30min), then examined bymyocardial contrast echocardiography (MCE) after10min. The imageswere stored and color-coded with DFY ultrasound imaging analysissoftware. Finally, researched the effect of ultrasound molecular imagingwith MBp in vivo.Results P-selectin antibody loaded targeted ultrasound contrastagent and model of myocardial ischemia-reperfusion were preparedsuccessfully. Color-coded showed that MBp produced significantlysignal enhancement in ischemia-reperfusion region of myocardium withMCE, and MBc produced slightly enhancement in the some region ofmyocardium with MCE.Conclusions Myocardial contrast echocardiography with P-selectintargeted ultrasound contrast agent can accurately detect ischemia-reperfusion injury after reperfusion therapy of acute myocardial ischemia.