[Impact of instantaneous uniformity of SonoVue microbubbles on binding characteristics of a new contrast agent targeted to choriocarcinoma cells in vitro].

BACKGROUND & OBJECTIVE: At present, the investigation of microbubble contrast agents is a hot spot. Although these contrast agents can increase the ultrasound detection rate of tumor vessels, they lack tissue specificity. This study was to evaluate the impact of instantaneous uniformity of SonoVue microbubbles on binding characteristics, including the adhesion rate and stability, of a new contrast agent targeted to choriocarcinoma cells (JARs) in vitro, in order to establish a foundation to explore targeted ultrasound imaging for localization of tumor cell antigens and increase the early diagnostic rate for tumors.

METHODS

The objects were divided into three groups: the uneven microbubble group (n=10), the uniform microbubble group (n=10) and the tiny microbubble group (n=10). The rosette formation rate was counted. JARs were calculated by flow cytometry (FCM). The shape of the rosette was recorded. The targeted contrast agent was prepared by mixing SonoVue microbubbles of different uniformity with rabbit anti-human chorionic gonadotrophin (HCG) antibody. The binding rates of the contrast agent to JARs before and after PBS rinse were analyzed.

RESULTS

The binding rate was significantlylower in the uneven microbubble group (60.4+/-1.5)% than in the uniform microbubble group (84.3+/-5.5)% and the tiny microbubble group (90.6+/-6.8)% (P<0.05). The binding rates of different microbubbles to JARs before and after PBS rinse were different. The uniform microbubbles were the most stable ones, with the binding rate of (84.3+/-5.5)% and (82.4+/-3.7)% before and after PBS rinse (P>0.05). The binding rates of the targeted microbubbles labeled with fluorescence to JARs were 72.9%, 81.03% and 88.5% in the uneven microbubble group, the uniform microbubble group and the tiny microbubble group, respectively (P<0.05).

CONCLUSIONS

The binding capacity of the targeted SonoVue microbubbles to JARs is related to instantaneous uniformity of the microbubble, which is determined by the shaking method before preparation. Improving instantaneous uniformity of SonoVue microbubbles may increase the binding rate and stability of targeted microbubbles to JARs, thus to improve the image of JARs.