Journal of Nuclear Medicine | |
The Advantage of Antibody Cocktails for Targeted Alpha Therapy Depends on Specific Activity | |
Roger W. Howell1  John M. Akudugu1  Jason D. Domogauer1  Jordan B. Pasternack1  Alisha Khullar1  | |
关键词: radioimmunotherapy; targeted alpha therapy; antibody cocktails; isolated tumor cells; disseminated tumor cells; flow cytometry; Monte Carlo; radionuclide; specific activity; alpha particle; | |
DOI : 10.2967/jnumed.114.141580 | |
学科分类:医学(综合) | |
来源: Society of Nuclear Medicine | |
【 摘 要 】
Nonuniform dose distributions among disseminated tumor cells can be a significant limiting factor in targeted α therapy. This study examines how cocktails of radiolabeled antibodies can be formulated to overcome this limitation. Methods: Cultured MDA-MB-231 human breast cancer cells were treated with different concentrations of a cocktail of 4 fluorochrome-conjugated monoclonal antibodies. The amount of each antibody bound to each cell was quantified using flow cytometry. A spreadsheet was developed to “arm†the antibodies with any desired radionuclide and specific activity, calculate the absorbed dose to each cell, and perform a Monte Carlo simulation of the surviving fraction of cells after exposure to cocktails of different antibody combinations. Simulations were performed for the α-particle emitters 211At, 213Bi, and 225Ac. Results: Activity delivered to the least labeled cell can be increased by 200%–400% with antibody cocktails, relative to the best-performing single antibody. Specific activity determined whether a cocktail or a single antibody achieved greater cell killing. With certain specific activities, cocktails outperformed single antibodies by a factor of up to 244. There was a profound difference (≤16 logs) in the surviving fraction when a uniform antibody distribution was assumed and compared with the experimentally observed nonuniform distribution. Conclusion: These findings suggest that targeted α therapy can be improved with customized radiolabeled antibody cocktails. Depending on the antibody combination and specific activity of the radiolabeled antibodies, cocktails can provide a substantial advantage in tumor cell killing. The methodology used in this analysis provides a foundation for pretreatment prediction of tumor cell survival in the context of personalized cancer therapy.
【 授权许可】
Unknown
【 预 览 】
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RO201912010199032ZK.pdf | 1218KB | download |