Dataset Information

Development of a ⁶⁴Cu-labeled CD4⁺ T cell targeting PET tracer: evaluation of CD4 specificity and its potential use in collagen-induced arthritis.

ABSTRACT:

Background

CD4⁺ T cells are central inflammatory mediators in the pathogenesis of autoimmune rheumatoid arthritis (RA), as they are one of the dominating cell types in synovial inflammation. Molecular imaging of CD4⁺ T cells has potential role for early detection and monitoring of RA. Here, we developed a new radiotracer for in vivo immunoPET imaging of murine CD4⁺ T cells and tested it in the collagen-induced arthritis (CIA) mouse model of human RA.

Results

The tracer, [⁶⁴Cu]Cu-NOTA-CD4-F(ab)'2 ([⁶⁴Cu]Cu-NOTA-CD4), was generated from F(ab)'2 fragments of R-anti-mouse CD4 antibodies conjugated to the 2-S-(isothiocyanatbenzyl)-1,4,7-triazacyclononane-1,4,7-triacetic acid (p-SCN-Bn-NOTA) chelator and radiolabeled with copper-64. Accumulation of the tracer and isotype control was evaluated in the CIA model and mice receiving whole-body irradiation (WBI) (5 Gy). The potential of [⁶⁴Cu]Cu-NOTA-CD4 for response assessment was evaluated in CIA induced mice treated with dexamethasone (DXM). Imaging data were compared with flow cytometry and immunohistochemistry (IHC) of inflammatory cells including CD4⁺ T cells. [⁶⁴Cu]Cu-NOTA-CD4 showed increased accumulation in T cell-rich tissues compared with isotype control (p < 0.0001). In addition, reduced accumulation of [⁶⁴Cu]Cu-NOTA-CD4 was observed in T cell-depleted tissue (p < 0.0001). Flow cytometry and IHC confirmed the increased infiltration of CD4⁺ T cells in CIA mice.

Conclusions

We developed and evaluated a new radiotracer, [⁶⁴Cu]Cu-NOTA-CD4, for immunoPET imaging of murine CD4⁺ T cells. [⁶⁴Cu]Cu-NOTA-CD4 was successfully synthesized by F(ab)'2 fragments of R-anti-mouse CD4 antibodies conjugated to a chelator and radiolabeled with copper-64. We found that our novel CD4 PET tracer can be used for noninvasive visualization of murine CD4⁺ T cells.

SUBMITTER: Clausen AS

PROVIDER: S-EPMC9481863 | biostudies-literature | 2022 Sep

REPOSITORIES: biostudies-literature

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Publications

Development of a <sup>64</sup>Cu-labeled CD4<sup>+</sup> T cell targeting PET tracer: evaluation of CD4 specificity and its potential use in collagen-induced arthritis.

Clausen Anne Skovsbo AS Christensen Camilla C Christensen Esben E Cold Sigrid S Kristensen Lotte Kellemann LK Hansen Anders Elias AE Kjaer Andreas A

EJNMMI research 20220916 1

<h4>Background</h4>CD4<sup>+</sup> T cells are central inflammatory mediators in the pathogenesis of autoimmune rheumatoid arthritis (RA), as they are one of the dominating cell types in synovial inflammation. Molecular imaging of CD4<sup>+</sup> T cells has potential role for early detection and monitoring of RA. Here, we developed a new radiotracer for in vivo immunoPET imaging of murine CD4<sup>+</sup> T cells and tested it in the collagen-induced arthritis (CIA) mouse model of human RA.<h4>R ...[more]

PMID: 36114433

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Dataset Information

Development of a ⁶⁴Cu-labeled CD4⁺ T cell targeting PET tracer: evaluation of CD4 specificity and its potential use in collagen-induced arthritis.

Background

Results

Conclusions

Publications

Development of a <sup>64</sup>Cu-labeled CD4<sup>+</sup> T cell targeting PET tracer: evaluation of CD4 specificity and its potential use in collagen-induced arthritis.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Dataset Information

Development of a 64Cu-labeled CD4+ T cell targeting PET tracer: evaluation of CD4 specificity and its potential use in collagen-induced arthritis.

Background

Results

Conclusions

Publications

Development of a <sup>64</sup>Cu-labeled CD4<sup>+</sup> T cell targeting PET tracer: evaluation of CD4 specificity and its potential use in collagen-induced arthritis.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Development of a ⁶⁴Cu-labeled CD4⁺ T cell targeting PET tracer: evaluation of CD4 specificity and its potential use in collagen-induced arthritis.