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Clinical and Translational Imaging

, Volume 5, Issue 1, pp 3–14 | Cite as

Current status of the development of PET radiotracers for imaging alpha synuclein aggregates in Lewy bodies and Lewy neurites

  • Paul T. Kotzbauer
  • Zhude Tu
  • Robert H. MachEmail author
Expert Review
Part of the following topical collections:
  1. Radiochemistry and radiopharmacology

Abstract

Purpose

This review provides an account of the current status of the development of PET radiotracers for imaging aggregated alpha synuclein (α-syn) in Lewy bodies and Lewy neurites. This includes a description of the various strategies used in the development of an α-syn PET probe and the technological hurdles which have limited progress in this area of research.

Methods

A survey of the literature describing small molecule-based probes that bind to α-syn and have served as lead compounds for PET radiotracer development was conducted. This literature review includes a description of various radiolabeled probes having a modest affinity for α-syn which have been published within the past 5 years.

Results

Although different chemical entities have been described as having a moderate affinity for α-syn, their in vitro binding affinities for α-syn and selectivities for α-syn versus beta amyloid (Aβ) and tau fibrils are not ideal for serving as lead compounds for PET radiotracer development. Structure–activity relationship (SAR) studies have generated radiolabeled probes capable of binding to α-syn, but selectivity versus Aβ and tau remains a problem.

Conclusions

The development of an optimal PET probe for imaging aggregated α-syn in Lewy bodies and Lewy neurites remains as a high priority in the field pf PET radiotracer development, since it would improve the diagnosis of PD and provide a biomarker for disease progression. An α-syn PET radiotracer would also be useful in the evaluation of the efficacy of therapeutic strategies aimed at reducing levels of α-syn in the CNS. Although much progress has been made in recent years, the development of a PET radiotracer for imaging α-syn aggregates represents an unmet need in field of translational PET imaging.

Keywords

Alpha synuclein Abeta Tau Lewy bodies Lewy neurites Parkinson’s disease 

Notes

Acknowledgements

The authors would like to acknowledge the Michael J. Fox Foundation for its continued support of the Alpha Synuclein Imaging Consortium.

Compliance with ethical standards

Conflict of interest

The authors have no conflicts of interest to disclose. This article does not contain any studies with human or animal subjects performed by the any of the authors.

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Copyright information

© Italian Association of Nuclear Medicine and Molecular Imaging 2016

Authors and Affiliations

  1. 1.Department of NeurologyWashington University School of MedicineSt. LouisUSA
  2. 2.Department of RadiologyWashington University School of MedicineSt. LouisUSA
  3. 3.Department of RadiologyUniversity of PennsylvaniaPhiladelphiaUSA

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