Competitive radiolabeled antibody imaging can determine the unlabeled intact antibody dose that fully blocks target binding but may be confounded by heterogeneous tumor penetration. We evaluated the hypothesis that smaller radiolabeled constructs can be used to more accurately evaluate tumor expressed receptors.
The Krogh cylinder distributed model, including bivalent binding and variable intervessel distances, simulated distribution of smaller constructs in the presence of increasing doses of labeled antibody forms.
Smaller constructs <25 kDa accessed binding sites more uniformly at large distances from blood vessels compared with larger constructs and intact antibody. These observations were consistent for different affinity and internalization characteristics of constructs. As predicted, a higher dose of unlabeled intact antibody was required to block binding to these distant receptor sites.
Small radiolabeled constructs provide more accurate information on total receptor expression in tumors and reveal the need for higher antibody doses for target receptor blockade.
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Beckman RA, Weiner LM, Davis HM (2007) Antibody constructs in cancer therapy: protein engineering strategies to improve exposure in solid tumors. Cancer 109:170–179
Beckman RA, von Roemeling R, Scott AM (2011) Monoclonal antibody dose determination and biodistribution into solid tumors. Ther Deliv 2:333–344
Thurber GM, Wittrup KD (2012) A mechanistic compartmental model for total antibody uptake in tumors. J Theor Biol 314:57–68
Kurai J, Chikumi H, Hashimoto K et al (2007) Antibody-dependent cellular cytotoxicity mediated by cetuximab against lung cancer cell lines. Clin Cancer Res 13:1552–1561
Meerten TV, van Rijn RS, Hol S et al (2006) Complement-induced cell death by rituximab depends on CD20 expression level and acts complementary to antibody-dependent cellular cytotoxicity. Clin Cancer Res 12:4027–4035
Bellosillo B, Villamor N, Lopez-Guillermo A et al (2001) Complement-mediated cell death induced by rituximab in B-cell lymphoproliferative disorders is mediated in vitro by a caspase-independent mechanism involving the generation of reactive oxygen species. Blood 98:2771–2777
Hendriks BS, Opresko LK, Wiley HS et al (2003) Quantitative analysis of HER2-mediated effects on HER2 and epidermal growth factor receptor endocytosis: distribution of homo- and heterodimers depends on relative her2 levels. J Biol Chem 278:23343–23351
Rudnick SI, Lou J, Shaller CC et al (2011) Influence of affinity and antigen internalization on the uptake and penetration of anti-HER2 antibodies in solid tumors. Cancer Res 71:2250–2259
Herter S, Herting F, Mundigl O et al (2013) Preclinical activity of the type II CD20 antibody GA101 (obinutuzumab) compared with rituximab and ofatumumab in vitro and in xenograft models. Mol Cancer Ther 12:2031–2042
Eiblmaier M, Meyer LA, Watson MA et al (2008) Correlating EGFR expression with receptor-binding properties and internalization of 64CU-DOTA-cetuximab in 5 cervical cancer cell lines. J Nucl Med 49:1472–1479
Krogh A (1919) The supply of oxygen to the tissues and the regulation of the capillary circulation. J Physiol 52(6):457–474
Thurber GM, Zajic SC, Wittrup KD (2007) Theoretic criteria for antibody penetration into solid tumors and micrometastases. J Nucl Med 48(6):995–999
Baxter LT, Jain RK (1996) Pharmacokinetic analysis of the microdistribution of enzyme-conjugated antibodies and prodrugs: comparison with experimental data. Br J Cancer 73(4):447–456
Lauk S, Zietman A, Skates S et al (1989) Comparative morphometric study of tumor vasculature in human squamous cell carcinomas and their xenotransplants in athymic nude mice. Cancer Res 49:4557–4561
Schmidt MM, Wittrup KD (2009) A modeling analysis of the effects of molecular size and binding affinity on tumor targeting. Mol Cancer Ther 8(10):2861–2871
Orcutt KD, Nasr KA, Whitehead DG et al (2011) Biodistribution and clearance of small molecule hapten chelates for pretargeted radioimmunotherapy. Mol Imaging Biol 13(2):215–221
Orlova A, Magnusson M, Eriksson TL et al (2006) Tumor imaging using a picomolar affinity HER2 binding affibody molecule. Cancer Res 66:4339–4348
Tolmachev V, Nilsson FY, Widstrom C et al (2006) 111In-benzyl-DTPA-ZHER2:342, an affibody-based conjugate for in vivo imaging of HER2 expression in malignant tumors. J Nucl Med 47:846–853
Williams LE, Wu AM, Yazaki PJ et al (2001) Numerical selection of optimal tumor imaging agents with application to engineered antibodies. Cancer Biother Radiopharm 16:25–35
Willuda J, Kubetzko S, Waibel R et al (2001) Tumor targeting of mono-, di-, and tetravalent anti-p185(HER-2) miniantibodies multimerized by self-associating peptides. J Biol Chem 276:14385–14392
Kubetzko S, Balic E, WWaibel R et al (2006) PEGylation and multimerization of the anti-p185HER-2 single chain Fv fragment 4D5: effects on tumor targeting. J Biol Chem 281:35186–35201
Tai M (1995) Targeting c-erbB-2 expressing tumors using single-chain Fv monomers and dimers. Cancer Res 55(23 Suppl):5983s–5989s
Nielsen UB, Adams GP, Weiner LM et al (2000) Targeting of bivalent anti-ErbB2 diabody antibody fragments to tumor cells is independent of the intrinsic antibody affinity. Cancer Res 60:6434–6440
Olafsen T, Kenanova VE, Sundaresan G et al (2005) Optimizing radiolabeled engineered anti-p185HER2 antibody fragments for in vivo imaging. Cancer Res 65:5907–5916
Olafsen T, Tan GJ, Cheung CW et al (2004) Characterization of engineered anti-p185HER-2 (scFv-CH3)2 antibody fragments (minibodies) for tumor targeting. Protein Eng Des Sel 17:315–323
Tsai SW, Sun Y, Williams LE et al (2000) Biodistribution and radioimmunotherapy of human breast cancer xenografts with radiometal-labeled DOTA conjugated anti-HER2/neu antibody 4D5. Biocong Chem 11:327–334
De Santes K, Slamon D, Anderson SK et al (1992) Radiolabeled antibody targeting of the HER-2/neu oncoprotein. Cancer Res 52:1916–1923
Pedley RB, Boden JA, Boden R et al (1994) The potential for enhanced tumour localization by poly(ethylene glycol) modification of anti-CEA antibody. Br J Cancer 70(6):1126–1130
Gutmann R, Leunig M, Feyh J et al (1995) Interstitial hypertension in head and neck tumors in patients: correlation with tumor size. Cancer Res 52:1993–1995
Graff CP, Wittrup KD (2003) Theoretical analysis of antibody targeting of tumor spheroids: importance of dosage for penetration, and affinity for retention. Cancer Res 63:1288–1296
Adams GP, Schier R, McCall AM et al (2001) High affinity restricts the localization and tumor penetration of single chain Fv antibody molecules. Cancer Res 61:4750–4755
Hussain S, Rodriguez-Fernandez M, Bruan GM et al (2014) Quantity and accessibility for specific targeting of receptors in tumors. Sci Rep 4:5232
Fujimori K, Covell DG, Fletcher JE et al (1990) A modeling analysis of monoclonal antibody percolation through tumors: a binding site barrier. J Nucl Med 31:1191–1198
Scott AM, Wolchok JD, Old LJ (2012) Antibody therapy of cancer. Nat Rev Cancer 12(4):278–287
Knowles SM, Wu AM (2012) Advances in immune-positron emission tomography: antibodies for molecular imaging in oncology. J Clin Oncol 30(31):3884–3892
Tichauer KM, Wang Y, Pogue BW et al (2015) Quantitative in vivo cell-surface receptor imaging in oncology: kinetic modeling and paired-agent principles from nuclear medicine and optical imaging. Phys Med Biol 60(14):R239–R269
Conflict of Interest
KDO and JH are full-time employees and stockholders of inviCRO. MS is a former employee and owns stock in inviCRO. JG is a full-time employee of Daiichi Sankyo, Inc. and owns stock in Daiichi Sankyo. MK is a full-time employee of Daiichi Sankyo. MM is a former employee and owns stock in Daiichi Sankyo. GPA and AMW are consultants to Daiichi Sankyo. GPA is a full-time employee of Viventia Bio. AMS has received funding/research support from Daiichi Sankyo. RAB is a former employee of Daiichi Sankyo and owns stock in Johnson and Johnson. This work was funded in part by Daiichi Sankyo, Inc.
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Orcutt, K.D., Adams, G.P., Wu, A.M. et al. Molecular Simulation of Receptor Occupancy and Tumor Penetration of an Antibody and Smaller Scaffolds: Application to Molecular Imaging. Mol Imaging Biol 19, 656–664 (2017). https://doi.org/10.1007/s11307-016-1041-y
- Receptor occupancy
- Tumor penetration
- Antibody imaging
- Antibody scaffolds
- Mathematical model
- Tumor antigen