Title :

A nanobody-based nuclear imaging tracer targeting dipeptidyl peptidase 6 to determine the mass of human beta cell grafts in mice.

Author(s) :

Demine, Stéphane [Auteur]
Université libre de Bruxelles [ULB]
Garcia Ribeiro, Rita [Auteur]
Vrije Universiteit Brussel [Bruxelles] [VUB]
Thevenet, Julien [Auteur]
Recherche translationnelle sur le diabète (RTD) - U1190
Marselli, Lorella [Auteur]
University of Pisa [Italy] = Università di Pisa [Italia] = Université de Pise [Italie] [UniPi]
Marchetti, Piero [Auteur]
University of Pisa [Italy] = Università di Pisa [Italia] = Université de Pise [Italie] [UniPi]
Pattou, Francois [Auteur]
Recherche translationnelle sur le diabète (RTD) - U1190
Pattou Kerr-Conte, Julie [Auteur]
Recherche translationnelle sur le diabète (RTD) - U1190
Devoogdt, Nick [Auteur]
Vrije Universiteit Brussel [Bruxelles] [VUB]
Eizirik, Decio L. [Auteur]
Université libre de Bruxelles [ULB]

Journal title :

Diabetologia

Abbreviated title :

Diabetologia

Volume number :

63

Pages :

825–836

Publication date :

2020-04

ISSN :

1432-0428

English keyword(s) :

Human islet imaging
Pancreatic beta cell imaging
Pancreatic beta cells
PET
SPECT
Type 1 diabetes

HAL domain(s) :

Sciences du Vivant [q-bio]

English abstract : [en]

Aims/hypothesis Type 1 diabetes is characterised by a progressive decline in beta cell mass. This is also observed following implantation of pancreatic islet allografts, but there is no reliable information regarding the ...
Show more >Aims/hypothesis Type 1 diabetes is characterised by a progressive decline in beta cell mass. This is also observed following implantation of pancreatic islet allografts, but there is no reliable information regarding the time course of beta cell loss. This is due to the limited availability of non-invasive pancreatic islet imaging techniques. We have previously described that dipeptidyl peptidase 6 (DPP6) is an alpha and beta cell-specific biomarker, and developed a camelid antibody (nanobody ‘4hD29’) against it. We demonstrated the possibility to detect DPP6-expressing cells by single-photon emission computed tomography (SPECT)/ computed tomography (CT), but the correlation between the number of cells grafted and the SPECT signal was not assessed. Here, we investigate whether the 4hD29 nanobody allows us to detect different amounts of human pancreatic islets implanted into immune-deficient mice. In addition, we also describe the adaptation of the probe for use with positron emission tomography (PET). Methods DPP6 expression was assessed in human samples using tissue arrays and immunohistochemistry. The effect of the 4hD29 nanobody on cell death and glucose-stimulated insulin secretion was measured in EndoC-βH1 cells and in human islets using Hoechst/propidium iodide staining and an anti-insulin ELISA, respectively. We performed in vivo SPECT imaging on severe combined immunodeficient (SCID) mice transplanted with different amounts of EndoC-βH1 cells (2 × 106, 5 × 106 and 10 × 106 cells), human islets (1000 and 3000) or pancreatic exocrine tissue using 99mTc-labelled 4hD29 nanobody. This DPP6 nanobody was also conjugated to N-chlorosuccinimide (NCS)-1,4,7-triazacyclononane-1,4,7-triacetic acid (NOTA), radiolabelled with either 67Ga (SPECT) or 68Ga (PET) and used in a proof-of-principle experiment to detect DPP6-expressing cells (Kelly neuroblastoma) grafted in SCID mice. Results The DPP6 protein is mainly expressed in pancreatic islets. Importantly, the anti-DPP6 nanobody 4hD29 allows non-invasive detection of high amounts of EndoC-βH1 cells or human islets grafted in immunodeficient mice. This suggests that the probe must be further improved to detect lower numbers of islet cells. The 4hD29 nanobody neither affected beta cell viability nor altered insulin secretion in EndoC-βH1 cells and human islets. The conversion of 4hD29 nanobody into a PET probe was successful and did not alter its specificity. Conclusions/interpretation These findings suggest that the anti-DPP6 4hD29 nanobody may become a useful tool for the quantification of human islet grafts in mice and, pending future development, islet mass in individuals with diabetes.Show less >

Language :

Anglais

Audience :

Internationale

Popular science :

Non

Administrative institution(s) :

Université de Lille
Inserm
CHU Lille

Collections :

• Recherche translationnelle sur le diabète (RTD) - U1190

Submission date :

2024-01-19T23:38:18Z
2024-09-17T12:54:42Z