Indium-111 radiolabelling of a brain-penetrant Aβ antibody for SPECT imaging
Abstract
Background: The development of bispecific antibodies that can traverse the blood–brain barrier has paved the way for brain-directed immunotherapy and when radiolabelled, immunoPET imaging. The objective of this study was to investigate how indium-111 (111In) radiolabelling with compatible chelators affects the brain delivery and peripheral biodistribution of the bispecific antibody RmAb158-scFv8D3, which binds to amyloid-beta (Aβ) and the transferrin receptor (TfR), in Aβ pathology-expressing tg-ArcSwe mice and aged-matched wild-type control mice.
Methods: Bispecific RmAb158-scFv8D3 (biAb) was radiolabelled with 111In using CHX-A”-DTPA, DOTA, or DOTA-tetrazine (DOTA-Tz). Affinity toward TfR and Aβ, as well as stability, was investigated in vitro. Mice were then intravenously administered with the three different radiolabelled biAb variants, and blood samples were collected for monitoring pharmacokinetics. Brain concentration was quantified after 2 and 72 h, and organ-specific retention was measured at 72 h by gamma counting. A subset of mice also underwent whole-body Single-photon emission computed tomography (SPECT) scanning at 72 h after injection. Following post-mortem isolation, the brains of tg-ArcSwe and WT mice were sectioned, and the spatial distribution of biAb was further investigated with autoradiography.
Results: All three [111In]biAb variants displayed similar blood pharmacokinetics and brain uptake at 2 h after administration. Radiolabelling did not compromise affinity, and all variants showed good stability, especially the DOTA-Tz variant. Whole-body SPECT scanning indicated high liver, spleen, and bone accumulation of all [111In]biAb variants. Subsequent ex vivo measurement of organ retention confirmed SPECT data, with retention in the spleen, liver, and bone – with very high bone marrow retention. Ex vivo gamma measurement of brain tissue, isolated at 72 h post-injection, and ex vivo autoradiography showed that WT mice, despite the absence of Aβ, exhibited comparable brain concentrations of [111In]biAb as those found in the tg-ArcSwe brain.
Conclusions: The successful 111In-labelling of biAb with retained binding to TfR and Aβ, and retained ability to enter the brain, demonstrated that 111In can be used to generate radioligands for brain imaging. A high degree of [111In]biAb in bone marrow and intracellular accumulation in brain tissue indicated some off-target interactions or potential interaction with intrabrain TfR resulting in a relatively high non-specific background signal.
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References
2. van Dyck CH, Swanson CJ, Aisen P, Bateman RJ, Chen C, Gee M, et al. Lecanemab in Early Alzheimer’s disease. N Engl J Med. 2023;388:9–21. doi: 10.1056/NEJMoa2212948
3. Budd Haeberlein S, Aisen PS, Barkhof F, Chalkias S, Chen T, Cohen S, et al. Two randomized phase 3 studies of aducanumab in early Alzheimer’s disease. J Prev Alzheimers Dis. 2022;9:197–210. doi: 10.14283/jpad.2022.30
4. Sevigny J, Chiao P, Bussiere T, Weinreb PH, Williams L, Maier M, et al. The antibody aducanumab reduces Abeta plaques in Alzheimer’s disease. Nature. 2016;537:50–6. doi: 10.1038/nature19323
5. Sims JR, Zimmer JA, Evans CD, Lu M, Ardayfio P, Sparks J, et al. Donanemab in early symptomatic Alzheimer disease: the TRAILBLAZER-ALZ 2 randomized clinical trial. JAMA. 2023;330:512–27. doi: 10.1001/jama.2023.13239
6. Swanson JD, Zhang Y, Dhadda S, Wang J, Kaplow J, Lai RYK, et al. A randomized, double-blind, phase 2b proof-of-concept clinical trial in early Alzheimer’s disease with lecanemab, an anti-Aβ protofibril antibody. Alzheimers Res Ther. 2021;17:80. doi: 10.1186/s13195-021-00813-8
7. Perl DP. Neuropathology of Alzheimer’s disease. Mt Sinai J Med. 2010;77:32–42. doi: 10.1002/msj.20157
8. Esparza TJ, Zhao H, Cirrito JR, Cairns NJ, Bateman RJ, Holtzman DM, et al. Amyloid-beta oligomerization in Alzheimer dementia versus high-pathology controls. Ann Neurol. 2013;73:104–19. doi: 10.1002/ana.23748
9. McLean CA, Cherny RA, Fraser FW, Fuller SJ, Smith MJ, Beyreuther K, et al. Soluble pool of Abeta amyloid as a determinant of severity of neurodegeneration in Alzheimer’s disease. Ann Neurol. 1999;46:860–6. doi: 10.1002/1531-8249(199912)46:6<860::aid-ana8>3.0.co;2-m
10. Englund H, Sehlin D, Johansson AS, Nilsson LN, Gellerfors P, Paulie S, et al. Sensitive ELISA detection of amyloid-beta protofibrils in biological samples. J Neurochem. 2007;103:334–45. doi: 10.1111/j.1471-4159.2007.04759.x
11. Syvanen S, Meier SR, Roshanbin S, Xiong M, Faresjo R, Gustavsson T, et al. PET imaging in preclinical anti-abeta drug development. Pharm Res. 2022;39:1481–96. doi: 10.1007/s11095-022-03277-z
12. Meier SR, Sehlin D, Roshanbin S, Falk VL, Saito T, Saido TC, et al. (11)C-PiB and (124)I-Antibody PET provide differing estimates of brain amyloid-beta after therapeutic intervention. J Nucl Med. 2022;63:302–9. doi: 10.2967/jnumed.121.262083
13. Meier SR, Syvanen S, Hultqvist G, Fang XT, Roshanbin S, Lannfelt L, et al. Antibody-based in vivo PET imaging detects amyloid-beta reduction in Alzheimer transgenic mice after BACE-1 inhibition. J Nucl Med. 2018;59:1885–91. doi: 10.2967/jnumed.118.213140
14. Sehlin D, Fang XT, Cato L, Antoni G, Lannfelt L, Syvanen S. Antibody-based PET imaging of amyloid beta in mouse models of Alzheimer’s disease. Nat Commun. 2016;7:10759. doi: 10.1038/ncomms10759
15. Sehlin D, Syvanen S. Engineered antibodies: new possibilities for brain PET? Eur J Nucl Med Mol Imaging. 2019;46:2848–58. doi: 10.1007/s00259-019-04426-0
16. Syvanen S, Fang XT, Hultqvist G, Meier SR, Lannfelt L, Sehlin D. A bispecific Tribody PET radioligand for visualization of amyloid-beta protofibrils – a new concept for neuroimaging. Neuroimage. 2017;148:55–63. doi: 10.1016/j.neuroimage.2017.01.004
17. Hultqvist G, Syvanen S, Fang XT, Lannfelt L, Sehlin D. Bivalent brain shuttle increases antibody uptake by monovalent binding to the transferrin receptor. Theranostics. 2017;7:308–18. doi: 10.7150/thno.17155
18. Kariolis MS, Wells RC, Getz JA, Kwan W, Mahon CS, Tong R, et al. Brain delivery of therapeutic proteins using an Fc fragment blood-brain barrier transport vehicle in mice and monkeys. Sci Transl Med. 2020;12(545). doi: 10.1126/scitranslmed.aay1359
19. Niewoehner J, Bohrmann B, Collin L, Urich E, Sade H, Maier P, et al. Increased brain penetration and potency of a therapeutic antibody using a monovalent molecular shuttle. Neuron. 2014;81:49–60. doi: 10.1016/j.neuron.2013.10.061
20. Yu YJ, Zhang Y, Kenrick M, Hoyte K, Luk W, Lu Y, et al. Boosting brain uptake of a therapeutic antibody by reducing its affinity for a transcytosis target. Sci Transl Med. 2011;3:84ra44. doi: 10.1126/scitranslmed.3002230
21. Syvanen S, Hultqvist G, Gustavsson T, Gumucio A, Laudon H, Soderberg L, et al. Efficient clearance of Abeta protofibrils in AbetaPP-transgenic mice treated with a brain-penetrating bifunctional antibody. Alzheimers Res Ther. 2018;10:49. doi: 10.1186/s13195-018-0377-8
22. Kissel K, Hamm S, Schulz M, Vecchi A, Garlanda C, Engelhardt B. Immunohistochemical localization of the murine transferrin receptor (TfR) on blood-tissue barriers using a novel anti-TfR monoclonal antibody. Histochem Cell Biol. 1998;110:63–72. doi: 10.1007/s004180050266
23. Gustavsson T, Syvanen S, O’Callaghan P, Sehlin D. SPECT imaging of distribution and retention of a brain-penetrating bispecific amyloid-beta antibody in a mouse model of Alzheimer’s disease. Transl Neurodegener. 2020;9:37. doi: 10.1186/s40035-020-00214-1
24. Greenwood FC, Hunter WM, Glover JS. The preparation of I-131-labelled human growth hormone of high specific radioactivity. Biochem J. 1963;89:114–23. doi: 10.1042/bj0890114
25. Price EW, Orvig C. Matching chelators to radiometals for radiopharmaceuticals. Chem Soc Rev. 2014;43:260–90. doi: 10.1039/c3cs60304k
26. Fang XT, Sehlin D, Lannfelt L, Syvanen S, Hultqvist G. Efficient and inexpensive transient expression of multispecific multivalent antibodies in Expi293 cells. Biol Proced Online. 2017;19:11. doi: 10.1186/s12575-017-0060-7
27. Loening AM, Gambhir SS. AMIDE: a free software tool for multimodality medical image analysis. Mol Imaging. 2003;2:131–7. doi: 10.1162/15353500200303133
28. Faresjo R, Bonvicini G, Fang XT, Aguilar X, Sehlin D, Syvanen S. Brain pharmacokinetics of two BBB penetrating bispecific antibodies of different size. Fluids Barriers CNS. 2021;18:26. doi: 10.1186/s12987-021-00257-0
29. Bien-Ly N, Yu YJ, Bumbaca D, Elstrott J, Boswell CA, Zhang Y, et al. Transferrin receptor (TfR) trafficking determines brain uptake of TfR antibody affinity variants. J Exp Med. 2014;211:233–44. doi: 10.1084/jem.20131660
30. Stergiou N, Wuensche TE, Schreurs M, Mes I, Verlaan M, Kooijman EJM, et al. Application of (89)Zr-DFO*-immuno-PET to assess improved target engagement of a bispecific anti-amyloid-ss monoclonal antibody. Eur J Nucl Med Mol Imaging. 2023;50:1306–17. doi: 10.1007/s00259-023-06109-3
31. Wuensche TE, Stergiou N, Mes I, Verlaan M, Schreurs M, Kooijman EJM, et al. Advancing (89)Zr-immuno-PET in neuroscience with a bispecific anti-amyloid-beta monoclonal antibody – the choice of chelator is essential. Theranostics. 2022;12:7067–79. doi: 10.7150/thno.73509
32. Sharkey RM, Behr TM, Mattes MJ, Stein R, Griffiths GL, Shih LB, et al. Advantage of residualizing radiolabels for an internalizing antibody against the B-cell lymphoma antigen, CD22. Cancer Immunol Immunother. 1997;44:179–88. doi: 10.1007/s002620050371
33. Moos T, Oates PS, Morgan EH. Expression of the neuronal transferrin receptor is age dependent and susceptible to iron deficiency. J Comp Neurol. 1998;398:420–30. doi: https://doi.org/10.1002/(SICI)1096-9861(19980831)398:3<420::AID-CNE8>3.3.CO;2-R
34. Moos T, Oates PS, Morgan EH. Iron-independent neuronal expression of transferrin receptor mRNA in the rat. Brain Res Mol Brain Res. 1999;72:231–4. doi: https://doi.org/10.1016/s0169-328x(99)00226-0
35. Wang W, Wang EQ, Balthasar JP. Monoclonal antibody pharmacokinetics and pharmacodynamics. Clin Pharmacol Ther. 2008;84:548–58. doi: https://doi.org/10.1038/clpt.2008.170
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