Laxman Bharathi, Hall Daniel E, Bhojani Mahaveer Swaroop, Hamstra Daniel A, Chenevert Thomas L, Ross Brian D, Rehemtulla Alnawaz
Center for Molecular Imaging, University of Michigan Medical School, 1150 West Medical Center Drive, Medical Sciences Research Building III, Room 9303, Ann Arbor, MI 48109-0648, USA.
Proc Natl Acad Sci U S A. 2002 Dec 24;99(26):16551-5. doi: 10.1073/pnas.252644499. Epub 2002 Dec 10.
Strict coordination of proliferation and programmed cell death (apoptosis) is essential for normal physiology. An imbalance in these two opposing processes results in various diseases including AIDS, neurodegenerative disorders, myelodysplastic syndromes, ischemiareperfusion injury, cancer, autoimmune disease, among others. Objective and quantitative noninvasive imaging of apoptosis would be a significant advance for rapid and dynamic screening as well as validation of experimental therapeutic agents. Here, we report the development of a recombinant luciferase reporter molecule that when expressed in mammalian cells has attenuated levels of reporter activity. In cells undergoing apoptosis, a caspase-3-specific cleavage of the recombinant product occurs, resulting in the restoration of luciferase activity that can be detected in living animals with bioluminescence imaging. The ability to image apoptosis noninvasively and dynamically over time provides an opportunity for high-throughput screening of proapoptotic and antiapoptotic compounds and for target validation in vivo in both cell lines and transgenic animals.
细胞增殖与程序性细胞死亡（凋亡）的严格协调对于正常生理功能至关重要。这两个相反过程的失衡会导致包括艾滋病、神经退行性疾病、骨髓增生异常综合征、缺血再灌注损伤、癌症、自身免疫性疾病等在内的各种疾病。对凋亡进行客观且定量的非侵入性成像，对于快速动态筛选以及实验治疗药物的验证而言将是一项重大进展。在此，我们报告了一种重组荧光素酶报告分子的研发情况，该分子在哺乳动物细胞中表达时报告活性水平会减弱。在经历凋亡的细胞中，重组产物会发生caspase - 3特异性切割，从而导致荧光素酶活性恢复，这种活性可通过生物发光成像在活体动物中检测到。随着时间的推移对凋亡进行非侵入性动态成像的能力，为高通量筛选促凋亡和抗凋亡化合物以及在细胞系和转基因动物体内进行靶点验证提供了契机。
