H-type dimer formation of fluorophores: a mechanism for activatable, in vivo optical molecular imaging.
H-type dimer formation of fluorophores: a mechanism for activatable, in vivo optical molecular imaging.
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DOI：
10.1021/cb900089j
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发表时间：
2009-07-17
影响因子：
4
通讯作者：
Kobayashi, Hisataka
中科院分区：
文献类型：
--
作者：
Ogawa, Mikako;Kosaka, Nobuyuki;Choyke, Peter L.;Kobayashi, Hisataka
使用靶特异性可激活的“智能”探针的体内分子成像（其仅在预期靶处产生荧光）由于高的靶与背景比（TBR）而使得能够进行灵敏和特异的癌症检测。二聚化和荧光淬灭已被证明发生在各种荧光团的浓缩水溶液中。在这里，我们假设，荧光团二聚化和淬灭后，共轭靶向蛋白质可以发生在低浓度，这是合理的在体内成像探针，因为蛋白质分子可以稳定的荧光团二聚体的基础上的物理化学相互作用。这种二聚化可以被利用作为荧光激活的机制。将罗丹明衍生物与分别靶向D-半乳糖受体和HER 2/neu抗原的癌靶向分子抗生物素蛋白和曲妥珠单抗偶联。缀合后，大比例的R6 G和塔姆拉形成H-型二聚体，即使在低浓度下，但在二聚体解离成单体时可以完全去淬灭。亲脂性是促进H-二聚体形成的潜在因素。为了证明体内荧光内窥镜分子成像期间的荧光激活效应，将高度淬灭的探针抗生物素蛋白-TAMRA或最低淬灭的探针抗生物素蛋白-Alexa 488施用到卵巢转移到腹膜的小鼠中。用抗生物素蛋白-TAMRA清楚地观察肿瘤，背景荧光低;相反，抗生物素蛋白-Alexa 488的背景荧光高。因此，H-二聚体形成作为荧光猝灭的机制可用于开发用于体内分子成像的荧光可激活探针。有效的可激活的光学探针可以通过聚焦于荧光团的H-二聚体形成来设计。
In vivo molecular imaging with target-specific activatable “smart” probes, which only yield fluorescence at the intended target, enables sensitive and specific cancer detection because of high target to background ratios (TBR). Dimerization and fluorescence quenching has been shown to occur in concentrated aqueous solutions of various fluorophores. Here, we hypothesized that fluorophore dimerization and quenching after conjugation to targeting proteins can occur at low concentration, which is reasonable for in vivo imaging probes, because protein molecules can stabilize the fluorophore dimers based on physico-chemical interactions. This dimerization can be exploited as a mechanism for fluorescence activation. Rhodamine derivatives were conjugated to the cancer targeting molecules, avidin and trastuzumab, which target D-galactose receptor and HER2/neu antigen, respectively. After conjugation, a large proportion of R6G and TAMRA formed H-type dimers, even at low concentrations, but could be fully dequenched upon dissociation of the dimers to monomers. Lipophilicity was a potential factor in promoting H-dimer formation. To demonstrate the fluorescence activation effect during in vivo fluorescence endoscopic molecular imaging, a highly quenched probe, avidin-TAMRA or a minimally quenched probe, avidin-Alexa488 was administered into mice with ovarian metastases to the peritoneum. The tumors were clearly visualized with avidin-TAMRA, with low background fluorescence; in contrast, the background fluorescence was high for avidin-Alexa488. Thus, H-dimer formation as a mechanism of fluorescence quenching could be used to develop fluorescence activatable probes for in vivo molecular imaging. Effective activatable optical probes can be designed by focusing on the H-dimer formation of fluorophores.
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影响因子：
5.7
作者：
Ogawa M;Regino CA;Choyke PL;Kobayashi H
通讯作者：
Kobayashi H
影响因子：
2.8
作者：
ARBELOA, IL;OJEDA, PR
通讯作者：
OJEDA, PR
影响因子：
3.6
作者：
Fujimoto, K;Shimizu, H;Inouye, M
通讯作者：
Inouye, M
影响因子：
82.9
作者：
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影响因子：
11.5
作者：
Hama, Yukihiro;Urano, Yasuteru;Kobayashi, Hisataka
通讯作者：
Kobayashi, Hisataka