[Detection of binding capability of targeted KDR ultrasound contrast agent in vitro for evaluating endometrial receptivity].
OBJECTIVE
To prepare a new targeted liposome ultrasonic contrast agent with anti-KDR antibody that binds specifically with KDR as the main receptor of VEGF and evaluate its physical characteristics, biological activity and specific binding capability in vitro.


METHODS
A sonicator was used to prepare the biotinylated lipid micro-bubbles (MB-B), and biotin-avidin-mediated technique was used for attachment of anti-mouse KDR monoclonal antibody to the micro-bubble shell to generate MB-BAB-KDR. MB-BAB-KDR was incubated with fluorescent second antibody to assess the link condition, and the control groups were the MB-B and micro-bubbles with the antibody alone (MB-B-KDR). A parallel plate flow chamber system was used to characterize micro-bubbles attachment efficiency to KDR Fc.


RESULTS
The surface of the micro-bubbles could carry KDR antibody through the biotin-avidin bridge and MB-BAB-KDR were spherical and well-distributed. After incubation with the second antibody, MB-BAB-KDR could be observed to emit bright green fluorescence (Grade II) as compared with little or weak fluorescence in the control MB-B group (Grade 0) and MB-B-KDR group (Grade I). Targeted micro-bubbles bound to KDR Fc increased as the KDR Fc concentration increased (P<0.05).


CONCLUSIONS
The targeted liposome contrast agent linked with KDR antibody by biotin-avidin bridge we prepared shows an increased binding number as the KDR Fc concentration increases, which provides a novel approach to molecular imaging study of endometrial receptivity.
Department of Ultrasound, Third Affiliated Hospital, Southern Medical University, Guangzhou 510630, China.E-mail: lmeihong@fimmu.com.
Hongmei
H
Liu
Xiaohua
X
Han
Li
L
Yang
Lijing
L
Ji
Sushu
S
Li
D000818:Animals; D000911:Antibodies, Monoclonal; D003287:Contrast Media / Q000737:chemistry*; D004717:Endometrium / Q000502:physiology; D005260:Female; D008081:Liposomes / Q000737:chemistry*; D051379:Mice; D045423:Microbubbles; D057054:Molecular Imaging; D013010:Sonication; D014463:Ultrasonography; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000276:immunology*
D000911:Antibodies, Monoclonal; D003287:Contrast Media; D008081:Liposomes; D040301:Vascular Endothelial Growth Factor Receptor-2