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Varasteh, Zohreh
Publications (10 of 31) Show all publications
Andersson, K. G., Rosestedt, M., Varasteh, Z., Malm, M., Sandström, M., Tolmachev, V., . . . Orlova, A. (2015). Comparative evaluation of 111In-labeled NOTA‑conjugated affibody molecules for visualization of HER3 expression in malignant tumors. Oncology Reports, 34(2), 1042-1048
Open this publication in new window or tab >>Comparative evaluation of 111In-labeled NOTA‑conjugated affibody molecules for visualization of HER3 expression in malignant tumors
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2015 (English)In: Oncology Reports, ISSN 1021-335X, E-ISSN 1791-2431, Vol. 34, no 2, p. 1042-1048Article in journal (Refereed) Published
Abstract [en]

Expression of human epidermal growth factor receptor type 3 (HER3) in malignant tumors has been associated with resistance to a variety of anticancer therapies. Several anti-HER3 monoclonal antibodies are currently under pre-clinical and clinical development aiming to overcome HER3-mediated resistance. Radionuclide molecular imaging of HER3 expression may improve treatment by allowing the selection of suitable patients for HER3-targeted therapy. Affibody molecules are a class of small (7 kDa) high-affinity targeting proteins with appreciable potential as molecular imaging probes. In a recent study, we selected affibody molecules with affinity to HER3 at a low picomolar range. The aim of the present study was to develop an anti-HER3 affibody molecule suitable for labeling with radiometals. The HEHEHE-Z08698-NOTA and HEHEHE-Z08699-NOTA HER3-specific affibody molecules were labeled with indium-111 (In-111) and assessed in vitro and in vivo for imaging properties using single photon emission computed tomography (SPECT). Labeling of HEHEHE-Z08698-NOTA and HEHEHE-Z08699-NOTA with In-111 provided stable conjugates. In vitro cell tests demonstrated specific binding of the two conjugates to HER3-expressing BT-474 breast carcinoma cells. In mice bearing BT-474 xenografts, the tumor uptake of the two conjugates was receptor-specific. Direct in vivo comparison of In-111-HEHEHE-Z08698-NOTA and In-111-HEHEHE-Z08699-NOTA demonstrated that the two conjugates provided equal radioactivity uptake in tumors, although the tumor-to-blood ratio was improved for In-111-HEHEHE-Z08698-NOTA [12 +/- 3 vs. 8 +/- 1,4 h post injection (p.i)] due to more efficient blood clearance. In-111-HEHEHE-Z08698-NOTA is a promising candidate for imaging of HER3-expression in malignant tumors using SPECT. Results of the present study indicate that this conjugate could be used for patient stratification for anti-HER3 therapy.

Keywords
NOTA, indium-111, affibody molecules, HER3, molecular imaging
National Category
Cancer and Oncology
Identifiers
urn:nbn:se:uu:diva-260279 (URN)10.3892/or.2015.4046 (DOI)000357965600060 ()26059265 (PubMedID)
Funder
Swedish Cancer SocietySwedish Research Council
Available from: 2015-08-21 Created: 2015-08-18 Last updated: 2018-09-20Bibliographically approved
Varasteh, Z. & Orlova, A. (2015). Comparing the measured affinity of (111) In-labeled ligands for cellular receptors by monitoring gamma, beta, or X-ray radiation with three different LigandTracer (R) devices. Journal of Radioanalytical and Nuclear Chemistry, 304(2), 823-828
Open this publication in new window or tab >>Comparing the measured affinity of (111) In-labeled ligands for cellular receptors by monitoring gamma, beta, or X-ray radiation with three different LigandTracer (R) devices
2015 (English)In: Journal of Radioanalytical and Nuclear Chemistry, ISSN 0236-5731, E-ISSN 1588-2780, Vol. 304, no 2, p. 823-828Article in journal (Refereed) Published
Abstract [en]

LigandTracer instruments measuring high energy photons (gamma-rays), particles (electrons and positrons) and low energy photons (X-rays) are novel semiautomated devices which produce real-time radiotracer-receptor interaction data for measurement of the affinity. The affinities of two different 111 In-labeled ligands were measured in three different LigandTracer devices detecting high energy gamma, Auger and internal conversion electrons, or X-rays. The obtained similar uptake/retention patterns (binding curves) show that even at low signal-to-noise ratios (data from Auger and internal conversion electrons, and X-rays), reliable binding data can be captured. This verifies that different devices could be used as alternatives for kinetic evaluation studies for radionuclides emitting different type of radiation.

Keywords
In-111, LigandTracer Yellow, LigandTracer White, LigandTracer Grey, Binding kinetics, Affinity
National Category
Chemical Sciences
Identifiers
urn:nbn:se:uu:diva-251967 (URN)10.1007/s10967-014-3875-6 (DOI)000351857600041 ()
Available from: 2015-05-18 Created: 2015-04-28 Last updated: 2017-12-04Bibliographically approved
Varasteh, Z., Mitran, B., Rosenström, U., Velikyan, I., Rosestedt, M., Lindeberg, G., . . . Orlova, A. (2015). The effect of macrocyclic chelators on the targeting properties of the 68Ga-labeled gastrin releasing peptide receptor antagonist PEG2-RM26. Nuclear Medicine and Biology, 42(5), 446-454
Open this publication in new window or tab >>The effect of macrocyclic chelators on the targeting properties of the 68Ga-labeled gastrin releasing peptide receptor antagonist PEG2-RM26
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2015 (English)In: Nuclear Medicine and Biology, ISSN 0969-8051, E-ISSN 1872-9614, Vol. 42, no 5, p. 446-454Article in journal (Refereed) Published
Abstract [en]

Introduction

Overexpression of gastrin-releasing peptide receptors (GRPR) has been reported in several cancers. Bombesin (BN) analogs are short peptides with a high affinity for GRPR. Different BN analogs were evaluated for radionuclide imaging and therapy of GRPR-expressing tumors. We have previously investigated an antagonistic analog of BN (D-Phe-Gln-Trp-Ala-Val-Gly-His-Sta-Leu-NH2, RM26) conjugated to NOTA via a PEG2 spacer (NOTA-PEG2-RM26) labeled with 68Ga, 111In and Al18F. 68Ga-labeled NOTA-PEG2-RM26 showed high tumor-to-organ ratios.

Methods

The influence of different macrocyclic chelators (NOTA, NODAGA, DOTA and DOTAGA) on the targeting properties of 68Ga-labeled PEG2-RM26 was studied in vitro and in vivo.

Results

All conjugates were labeled with generator-produced 68Ga with high yields and demonstrated high stability and specific binding to GRPR. The IC50 values of natGa-X-PEG2-RM26 (X = NOTA, DOTA, NODAGA, DOTAGA) were 2.3 ± 0.2, 3.0 ± 0.3, 2.9 ± 0.3 and 10.0 ± 0.6 nM, respectively. The internalization of the conjugates by PC-3 cells was low. However, the DOTA-conjugated analog demonstrated a higher internalization rate compared to other analogs. GRPR-specific uptake was found in receptor-positive normal tissues and PC-3 xenografts for all conjugates. The biodistribution of the conjugates was influenced by the choice of the chelator moiety. Although all radiotracers cleared rapidly from the blood, [68Ga]Ga-NOTA-PEG2-RM26 showed significantly lower uptake in lung, muscle and bone compared to the other analogs. The uptake in tumors (5.40 ± 1.04 %ID/g at 2 h p.i.) and the tumor-to-organ ratios (25 ± 3, 157 ± 23 and 39 ± 4 for blood, muscle and bone, respectively) were significantly higher for the NOTA-conjugate than the other analogs.

Conclusions

Chelators had a clear influence on the biodistribution and targeting properties of 68Ga-labeled antagonistic BN analogs. Positively charged [68Ga]Ga-NOTA-PEG2-RM26 provided a low kidney radioactivity uptake, high affinity, high tumor uptake and high image contrast.

National Category
Radiology, Nuclear Medicine and Medical Imaging
Identifiers
urn:nbn:se:uu:diva-232120 (URN)10.1016/j.nucmedbio.2014.12.009 (DOI)000353369000005 ()25684649 (PubMedID)
Funder
Swedish Cancer SocietySwedish Research Council
Available from: 2014-09-12 Created: 2014-09-12 Last updated: 2019-07-17Bibliographically approved
Andersson, K. G., Varasteh, Z., Rosestedt, M., Malm, M., Sandström, M., Tolmachev, V., . . . Orlova, A. (2014). 111In-labeled NOTA-conjugated Affibody molecules for visualization of HER3 expression in malignant tumors. Paper presented at Annual Congress of the European-Association-of-Nuclear-Medicine (EANM), OCT 18-22, 2014, Gothenburg, SWEDEN. European Journal of Nuclear Medicine and Molecular Imaging, 41(S2), S311-S311, Article ID OP681.
Open this publication in new window or tab >>111In-labeled NOTA-conjugated Affibody molecules for visualization of HER3 expression in malignant tumors
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2014 (English)In: European Journal of Nuclear Medicine and Molecular Imaging, ISSN 1619-7070, E-ISSN 1619-7089, Vol. 41, no S2, p. S311-S311, article id OP681Article in journal, Meeting abstract (Other academic) Published
National Category
Radiology, Nuclear Medicine and Medical Imaging
Identifiers
urn:nbn:se:uu:diva-247687 (URN)000348841900497 ()
Conference
Annual Congress of the European-Association-of-Nuclear-Medicine (EANM), OCT 18-22, 2014, Gothenburg, SWEDEN
Available from: 2015-03-24 Created: 2015-03-23 Last updated: 2017-12-04Bibliographically approved
Altai, M., Wållberg, H., Honarvar, H., Strand, J., Orlova, A., Varasteh, Z., . . . Tolmachev, V. (2014). 188Re-ZHER2:V2, a promising affibody-based targeting agent against HER2-expressing tumors: preclinical assessment. Journal of Nuclear Medicine, 55(11), 1842-1848
Open this publication in new window or tab >>188Re-ZHER2:V2, a promising affibody-based targeting agent against HER2-expressing tumors: preclinical assessment
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2014 (English)In: Journal of Nuclear Medicine, ISSN 0161-5505, E-ISSN 1535-5667, Vol. 55, no 11, p. 1842-1848Article in journal (Refereed) Published
Abstract [en]

Affibody molecules are small (7 kDa) nonimmunoglobulin scaffold proteins with favorable tumor-targeting properties. Studies concerning the influence of chelators on biodistribution of 99mTc-labeled Affibody molecules demonstrated that the variant with a C-terminal glycyl-glycyl-glycyl-cysteine peptide–based chelator (designated ZHER2:V2) has the best biodistribution profile in vivo and the lowest renal retention of radioactivity. The aim of this study was to evaluate 188Re-ZHER2:V2 as a potential candidate for radionuclide therapy of human epidermal growth factor receptor type 2 (HER2)–expressing tumors.

Methods:

ZHER2:V2 was labeled with 188Re using a gluconate-containing kit. Targeting of HER2-overexpressing SKOV-3 ovarian carcinoma xenografts in nude mice was studied for a dosimetry assessment.

Results:

Binding of 188Re-ZHER2:V2 to living SKOV-3 cells was demonstrated to be specific, with an affinity of 6.4 ± 0.4 pM. The biodistribution study showed a rapid blood clearance (1.4 ± 0.1 percentage injected activity per gram [%ID/g] at 1 h after injection). The tumor uptake was 14 ± 2, 12 ± 2, 5 ± 2, and 1.8 ± 0.5 %IA/g at 1, 4, 24, and 48 h after injection, respectively. The in vivo targeting of HER2-expressing xenografts was specific. Already at 4 h after injection, tumor uptake exceeded kidney uptake (2.1 ± 0.2 %IA/g). Scintillation-camera imaging showed that tumor xenografts were the only sites with prominent accumulation of radioactivity at 4 h after injection. Based on the biokinetics, a dosimetry evaluation for humans suggests that 188Re-ZHER2:V2 would provide an absorbed dose to tumor of 79 Gy without exceeding absorbed doses of 23 Gy to kidneys and 2 Gy to bone marrow. This indicates that future human radiotherapy studies may be feasible.

Conclusion:

188Re-ZHER2:V2 can deliver high absorbed doses to tumors without exceeding kidney and bone marrow toxicity limits.

National Category
Radiology, Nuclear Medicine and Medical Imaging
Identifiers
urn:nbn:se:uu:diva-211593 (URN)10.2967/jnumed.114.140194 (DOI)000344209200015 ()25278516 (PubMedID)
Available from: 2013-12-03 Created: 2013-11-27 Last updated: 2017-12-06Bibliographically approved
Varasteh, Z. (2014). Bombesin Antagonists for Targeting Gastrin-Releasing Peptide Receptor-Positive Tumors: Design, Synthesis, Preclinical Evaluation and Optimization of Imaging Agents . (Doctoral dissertation). Uppsala: Acta Universitatis Upsaliensis
Open this publication in new window or tab >>Bombesin Antagonists for Targeting Gastrin-Releasing Peptide Receptor-Positive Tumors: Design, Synthesis, Preclinical Evaluation and Optimization of Imaging Agents
2014 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

This thesis is focused on the development, preclinical evaluation, and optimization of radiotracers for the detection of gastrin-releasing peptide receptor (GRPR)-expressing tumors. The work is divided into three distinct parts: (1) the development of bombesin (BN) antagonist (RM26)-based imaging radiotracers for the detection of GRPR-expressing tumors using different positron emission tomography (PET) and single photon emission computed tomography (SPECT) radionuclides (68Ga, 18F and 111In), (2) the establishment of a method to monitor the ligand-G protein-coupled receptor (GPCR) interaction in real time without requiring purification and stabilization of the receptors, and (3) the evaluation of radiopeptide structure-related factors (length of mini-PEG linker and composition of chelator for metal labeling) affecting the in vitro and in vivo characteristics of RM26-based tracers.

We demonstrated the possibility of high-contrast in vivo imaging of GRPR-expressing xenografts despite the physiological expression of GRPR in abdominal organs. Fast radioactivity clearance from the blood and healthy organs, including receptor-positive organs, and long retention in the tumors resulted in high tumor-to-background ratios. A novel real-time assay for measuring the kinetics of the radiotracers targeting GPCR was evaluated. Living cells were used instead of purified receptors in this technology, bringing the developmental work one step closer to the true target environment (imaging in living systems). The comparative study of 68Ga-labeled NOTA-PEGn-RM26 with di-, tri-, tetra- and hexaethylene glycol chains demonstrated that the addition of only a few units of ethylene glycol to the spacer is insufficient to appreciably affect the biodistribution of the radiopeptide. Finally, a comparative study of 68Ga-labeled PEG2-RM26 analogs N-terminally conjugated to NOTA, NODAGA, DOTA or DOTAGA highlighted the influence of the chelator on the targeting properties of the radiopeptide.

The main conclusion that can be drawn from this thesis is that 68Ga-NOTA-PEG2-RM26 has favorable biodistribution properties, such as rapid clearance from blood and tissues with physiological GRPR expression levels and long retention in GRPR-expressing tumors, and that this radiopeptide is potentially suitable for initial clinical investigation.

Place, publisher, year, edition, pages
Uppsala: Acta Universitatis Upsaliensis, 2014. p. 66
Series
Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Pharmacy, ISSN 1651-6192 ; 191
Keywords
Bombesin, Gastrin-releasing peptide receptor (GRPR), Antagonist, Radionuclide molecular imaging
National Category
Pharmaceutical Sciences
Identifiers
urn:nbn:se:uu:diva-232123 (URN)978-91-554-9039-3 (ISBN)
Public defence
2014-10-31, Rudbecksalen, Dag Hammarskjölds väg 20, Uppsala, 09:00 (English)
Opponent
Supervisors
Available from: 2014-10-10 Created: 2014-09-12 Last updated: 2018-01-11
Strand, J., Varasteh, Z., Eriksson, O., Abrahmsen, L., Orlova, A. & Tolmachev, V. (2014). Gallium-68-labeled affibody molecule for PET imaging of PDGFR beta expression in vivo. Paper presented at Annual Congress of the European-Association-of-Nuclear-Medicine (EANM), OCT 18-22, 2014, Gothenburg, SWEDEN. European Journal of Nuclear Medicine and Molecular Imaging, 41(S2), S262-S262, Article ID OP469.
Open this publication in new window or tab >>Gallium-68-labeled affibody molecule for PET imaging of PDGFR beta expression in vivo
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2014 (English)In: European Journal of Nuclear Medicine and Molecular Imaging, ISSN 1619-7070, E-ISSN 1619-7089, Vol. 41, no S2, p. S262-S262, article id OP469Article in journal, Meeting abstract (Other academic) Published
National Category
Radiology, Nuclear Medicine and Medical Imaging
Identifiers
urn:nbn:se:uu:diva-247706 (URN)000348841900331 ()
Conference
Annual Congress of the European-Association-of-Nuclear-Medicine (EANM), OCT 18-22, 2014, Gothenburg, SWEDEN
Available from: 2015-03-25 Created: 2015-03-23 Last updated: 2017-12-04Bibliographically approved
Strand, J., Varasteh, Z., Eriksson, O., Abrahmsen, L., Orlova, A. & Tolmachev, V. (2014). Gallium-68-Labeled Affibody Molecule for PET Imaging of PDGFRβ Expression in Vivo. Molecular Pharmaceutics, 11(11), 3957-3964
Open this publication in new window or tab >>Gallium-68-Labeled Affibody Molecule for PET Imaging of PDGFRβ Expression in Vivo
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2014 (English)In: Molecular Pharmaceutics, ISSN 1543-8384, E-ISSN 1543-8392, Vol. 11, no 11, p. 3957-3964Article in journal (Refereed) Published
Abstract [en]

Platelet-derived growth factor receptor β (PDGFRβ) is a transmembrane tyrosine kinase receptor involved, for example, in angiogenesis. Overexpression and excessive signaling of PDGFRβ has been observed in multiple malignant tumors and fibrotic diseases, making this receptor a pharmaceutical target for monoclonal antibodies and tyrosine kinase inhibitors. Successful targeted therapy requires identification of responding patients. Radionuclide molecular imaging would enable determination of the PDGFRβ status in all lesions using a single noninvasive repeatable procedure. Recently, we have demonstrated that the affibody molecule Z09591 labeled with 111In can specifically target PDGFRβ-expressing tumors in vivo. The use of positron emission tomography (PET) as an imaging technique would provide superior resolution, sensitivity, and quantitation accuracy. In this study, a DOTA-conjugated Z09591 was labeled with the generator-produced positron emitting radionuclide 68Ga (T1/2 = 67.6 min, Eβ + max = 1899 keV, 89% β+). 68Ga-DOTA-Z09591 retained the capacity to specifically bind to PDGFRβ-expressing U-87 MG glioma cells. The half-maximum inhibition concentration (IC50) of 68Ga-DOTA-Z09591 (6.6 ± 1.4 nM) was somewhat higher than that of 111In-DOTA-Z09591 (1.4 ± 1.2 nM). 68Ga-DOTA-Z09591 demonstrated specific (saturable) targeting of U-87 MG xenografts in immunodeficient mice. The tumor uptake at 2 h after injection was 3.7 ± 1.7% IA/g, which provided a tumor-to-blood ratio of 8.0 ± 3.1. The only organ with higher accumulation of radioactivity was the kidney. MicroPET imaging provided high-contrast imaging of U-87 MG xenografts. In conclusion, the 68Ga-labeled affibody molecule Z09591 is a promising candidate for further development as a probe for imaging PDGFRβ expression in vivo using PET.

National Category
Medical Biotechnology
Identifiers
urn:nbn:se:uu:diva-235390 (URN)10.1021/mp500284t (DOI)000344307700020 ()24972112 (PubMedID)
Funder
Swedish Cancer SocietySwedish Research Council
Available from: 2014-11-01 Created: 2014-11-01 Last updated: 2017-12-05Bibliographically approved
Orlova, A., Malm, M., Rosestedt, M., Varasteh, Z., Andersson, K., Selvaraju, R. K., . . . Löfblom, J. (2014). Imaging of HER3-expressing xenografts in mice using a (99m)Tc(CO) 3-HEHEHE-Z HER3 08699 affibody molecule. European Journal of Nuclear Medicine and Molecular Imaging, 41(7), 1450-1459
Open this publication in new window or tab >>Imaging of HER3-expressing xenografts in mice using a (99m)Tc(CO) 3-HEHEHE-Z HER3 08699 affibody molecule
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2014 (English)In: European Journal of Nuclear Medicine and Molecular Imaging, ISSN 1619-7070, E-ISSN 1619-7089, Vol. 41, no 7, p. 1450-1459Article in journal (Refereed) Published
Abstract [en]

PURPOSE: Human epidermal growth factor receptor type 3 (HER3) is a transmembrane receptor tyrosine kinase belonging to the HER (ErbB) receptor family. Membranous expression of HER3 is associated with trastuzumab resistance in breast cancer and the transition to androgen independence in prostate cancer. Imaging of HER3 expression in malignant tumors may provide important diagnostic information that can influence patient management. Affibody molecules with low picomolar affinity to HER3 were recently selected. The aim of this study was to investigate the feasibility of HER3 imaging using radiolabeled Affibody molecules.

METHODS: A HER3-binding Affibody molecule, Z08699, with a HEHEHE-tag on N-terminus was labeled with (99m)Tc(CO)3 using an IsoLink kit. In vitro and in vivo binding specificity and the cellular processing of the labeled binder were evaluated. Biodistribution of (99m)Tc(CO)3-HEHEHE-Z08699 was studied over time in mice bearing HER3-expressing xenografts.

RESULTS: HEHEHE-Z08699 was labeled with (99m)Tc(CO)3 with an isolated yield of >80 % and a purity of >99 %. Binding of (99m)Tc(CO)3-HEHEHE-Z08699 was specific to BT474 and MCF7 (breast cancer), and LS174T (colon cancer) cells. Cellular processing showed rapid binding and relatively quick internalization of the receptor/Affibody molecule complex (70 % of cell-associated radioactivity was internalized after 24 h). The tumor targeting was receptor mediated and the excretion was predominantly renal. Receptor-mediated uptake was also found in the liver, lung, stomach, intestine, and salivary glands. At 4 h pi, tumor-to-blood ratios were 7 ± 3 for BT474, and 6 ± 2 for LS174T xenografts. LS174T tumors were visualized by microSPECT 4 h pi.

CONCLUSIONS: The results of this study suggest the feasibility of HER3-imaging in malignant tumors using Affibody molecules.

National Category
Pharmaceutical Sciences
Identifiers
urn:nbn:se:uu:diva-220474 (URN)10.1007/s00259-014-2733-7 (DOI)000337286200021 ()24622956 (PubMedID)
Available from: 2014-03-15 Created: 2014-03-15 Last updated: 2018-01-11Bibliographically approved
Tolmachev, V., Varasteh, Z., Honarvar, H., Hosseinimehr, S. J., Eriksson, O., Jonasson, P., . . . Orlova, A. (2014). Imaging of platelet-derived growth factor receptor β expression in glioblastoma xenografts using affibody molecule 111In-DOTA-Z09591. Journal of Nuclear Medicine, 55(2), 294-300
Open this publication in new window or tab >>Imaging of platelet-derived growth factor receptor β expression in glioblastoma xenografts using affibody molecule 111In-DOTA-Z09591
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2014 (English)In: Journal of Nuclear Medicine, ISSN 0161-5505, E-ISSN 1535-5667, Vol. 55, no 2, p. 294-300Article in journal (Refereed) Published
Abstract [en]

The overexpression and excessive signaling of platelet-derived growth factor receptor β (PDGFRβ) has been detected in cancers, atherosclerosis, and a variety of fibrotic diseases. Radionuclide in vivo visualization of PDGFRβ expression might help to select PDGFRβ targeting treatment for these diseases. The goal of this study was to evaluate the feasibility of in vivo radionuclide imaging of PDGFRβ expression using an Affibody molecule, a small nonimmunoglobulin affinity protein.

Methods

The PDGFRβ-binding Z09591 Affibody molecule was site-specifically conjugated with a maleimido derivative of DOTA and labeled with 111In. Targeting of the PDGFRβ-expressing U-87 MG glioblastoma cell line using 111In-DOTA-Z09591 was evaluated in vitro and in vivo.

Results

DOTA-Z09591 was stably labeled with 111In with preserved specific binding to PDGFRβ-expressing cells in vitro. The dissociation constant for 111In-DOTA-Z09591 binding to U-87 MG cells was determined to be 92 ± 10 pM. In mice bearing U-87 MG xenografts, the tumor uptake of 111In-DOTA-Z09591 was 7.2 ± 2.4 percentage injected dose per gram and the tumor-to-blood ratio was 28 ± 14 at 2 h after injection. In vivo receptor saturation experiments demonstrated that targeting of U-87 MG xenografts in mice was PDGFRβ-specific. U-87 MG xenografts were clearly visualized using small-animal SPECT/CT at 3 h after injection.

Conclusion

This study demonstrates the feasibility of in vivo visualization of PDGFRβ-expressing xenografts using an Affibody molecule. Further development of radiolabeled Affibody molecules might provide a useful clinical imaging tool for PDGFRβ expression during various pathologic conditions.

National Category
Medical and Health Sciences
Identifiers
urn:nbn:se:uu:diva-218568 (URN)10.2967/jnumed.113.121814 (DOI)000330926200047 ()24408895 (PubMedID)
Available from: 2014-02-12 Created: 2014-02-12 Last updated: 2017-12-06Bibliographically approved
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