Nuklearmedizin 2021; 60(02): 188
DOI: 10.1055/s-0041-1727079
WIS-Poster
Varia

111In-exendin SPECT imaging suggests presence of residual beta cells in patients with longstanding type 1 diabetes

M Boss
1   Radboud University Medical Center, Department of Medical Imaging, Nijmegen
,
I Kusmartseva
2   University of Florida, Department of Pathology, Immunology and Laboratory Medicine, Florida
,
W Woliner- van der Weg
1   Radboud University Medical Center, Department of Medical Imaging, Nijmegen
,
L Joosten
1   Radboud University Medical Center, Department of Medical Imaging, Nijmegen
,
M Brom
1   Radboud University Medical Center, Department of Medical Imaging, Nijmegen
,
M Behe
3   Paul Scherrer institute, Center for Radiopharmaceutical Sciences, Villingen
,
C Tack
4   Radboud University Medical Center, Department of Internal Medicine, Nijmegen
,
B de Galan
4   Radboud University Medical Center, Department of Internal Medicine, Nijmegen
,
O Boerman
1   Radboud University Medical Center, Department of Medical Imaging, Nijmegen
,
M Janssen
1   Radboud University Medical Center, Department of Medical Imaging, Nijmegen
,
M Atkinson
5   University of Florida, UF Diabetes Institute, Florida
,
M Gotthardt
1   Radboud University Medical Center, Department of Medical Imaging, Nijmegen
› Author Affiliations
› Further Information
 
 

    Ziel/Aim There is increasing evidence for residual, dysfunctional beta cells in patients with type 1 diabetes (T1D), but research is hampered by the lack of methods to quantify beta cell mass (BCM) in vivo in humans. Image-based quantification of BCM using radiolabeled exendin-4 might provide such a method.

    Methodik/Methods Ten T1D patients and ten matched healthy controls underwent quantitative SPECT following injection of 150 MBq 111In-exendin-4 after which pancreatic tracer uptake was determined. In addition, immunohistochemical analysis of human pancreatic sections from organ donors with longstanding T1D (C-peptide negative) was performed to assess GLP-1R expression, insulin, glucagon and somatostatin.

    Ergebnisse/Results Tracer uptake was above background levels in 6/10 individuals with T1D and even comparable to levels in healthy controls in 5/10 patients. In all remaining patients, only background uptake (~10 % of the mean uptake in T1D patients) was observed. Uptake was independent of stimulated C-peptide levels (<0.03 nmol/L in 8/10 patients). Immunohistochemistry demonstrated insulin/GLP-1R positive cells in 12/19 cases, explaining the high radiotracer uptake found in a subgroup of T1D patients. Furthermore, insulin-negative/GLP-1R positive cells were found, which proved to be somatostatin-positive, showing GLP-1R expression on delta cells, explaining the background tracer uptake in patients without remaining beta cells.

    Schlussfolgerungen/Conclusions Quantitative exendin imaging was able to show differences in beta cell mass between patients and uncover the presence of residual beta cells in a subgroup of patients with T1D with low and stable background uptake levels. This demonstrates the value of this technique for in vivo determination of human pancreatic BCM and its potential use as a tool to further elucidate the complex pathophysiology of diabetes or study the effect of various interventions on BCM.


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    Publication History

    Article published online:
    08 April 2021

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