Fluorescence imaging of APP in Alzheimer's disease with quantum dot or Cy3: a comparative study
10.3969/j.issn.1672-7347.2010.09.001
- VernacularTitle:量子点及Cy3免疫荧光染色标记阿尔茨海默病转基因细胞模型APP的比较研究
- Author:
Li FENG
;
Shuyu LI
;
Bo XIAO
;
Si CHEN
;
Renkai LIU
;
Yong ZHANG
- Publication Type:Journal Article
- Keywords:
Alzheimer's disease;
quantum dot;
β-amyloid precursor protein;
molecular imaging
- From:
Journal of Central South University(Medical Sciences)
2010;35(9):903-909
- CountryChina
- Language:Chinese
-
Abstract:
Objective To compare the fluorescence intensity and duration of qdots streptavidin conjugate (QDs-SA) with Cy3 as the molecular probe of β amyloid precursor protein (APP), and to provide evidence for early molecular imaging and diagnosis of Alzheimer's dissease (AD). Methods With the help of laser scanning confocal microscope and flow cytometry, the flurescence probe based on the QDs-SA was used to detect APP in HEK293 cells stably transfected pcDNA3.1/APP, and to compare with conventional fluroimmunoassay Cy3. Results The immunofluorescence staining detection indicated APP expression was mainly located in the plasma membrane. The mean fluorescence intensity of QDs-SA (34.2336±4.2455) was greater than that of Cy3 (21.6023±3.0102)under the confocal fluorescence microscope (P<0.05). After persistent exciting for 12 min, the fluorescence intensity of APP stained by QDs-SA decreased by 27.87%. The other stained by Cy3 decreased by 79.60%. The positive rate of APP staining had no significant difference between the QDs-SA(54.4700±3.4433)% and Cy3 (54.3800±8.5229)% by flow cytometry, but the mean fluorescence intensity had statistical significance(P<0.05). The QDs-SA (1 045.4167±47.3623) was significantly higher than the mean fluorescence intensity of Cy3 (658.5467±55.0591). Conclusion QDs-SA fluorescence probes can effectively recognize APP and are sensitive and exceptionally photostable, suggesting that QDs-SA fluorescence probes could be a potential method in APP detection and offer a novel way for the diagnosis of Alzheimer's disease.
