Dataset Information

In Vivo Imaging of Local Inflammation: Monitoring LPS-Induced CD80/CD86 Upregulation by PET.

ABSTRACT:

Purpose

The co-stimulatory molecules CD80 and CD86 are upregulated on activated antigen-presenting cells (APC). We investigated whether local APC activation, induced by subcutaneous (s.c.) inoculation of lipopolysaccharides (LPS), can be imaged by positron emission tomography (PET) with CD80/CD86-targeting ⁶⁴Cu-labelled abatacept.

Procedures

Mice were inoculated s.c. with extracellular-matrix gel containing either LPS or vehicle (PBS). Immune cell populations were analysed by flow cytometry and marker expression by RT-qPCR. ⁶⁴Cu-NODAGA-abatacept distribution was analysed using PET/CT and ex vivo biodistribution.

Results

The number of CD80⁺ and CD86⁺ immune cells at the LPS inoculation site significantly increased a few days after inoculation. CD68 and CD86 expression were higher at the LPS than the PBS inoculation site, and CD80 was only increased at the LPS inoculation site. CTLA-4 was highest 10 days after LPS inoculation, when CD80/CD86 decreased again. A few days after inoculation, ⁶⁴Cu-NODAGA-abatacept distribution to the inoculation site was significantly higher for LPS than PBS (4.2-fold). Co-administration of unlabelled abatacept or human immunoglobulin reduced tracer uptake. The latter reduced the number of CD86⁺ immune cells at the LPS inoculation site.

Conclusions

CD80 and CD86 are upregulated in an LPS-induced local inflammation, indicating invasion of activated APCs. ⁶⁴Cu-NODAGA-abatacept PET allowed following APC activation over time.

SUBMITTER: Taddio MF

PROVIDER: S-EPMC7910267 | biostudies-literature | 2021 Apr

REPOSITORIES: biostudies-literature

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Publications

In Vivo Imaging of Local Inflammation: Monitoring LPS-Induced CD80/CD86 Upregulation by PET.

Taddio Marco F MF Castro Jaramillo Claudia A CA Runge Peter P Blanc Alain A Keller Claudia C Talip Zeynep Z Béhé Martin M van der Meulen Nicholas P NP Halin Cornelia C Schibli Roger R Krämer Stefanie D SD

Molecular imaging and biology 20200928 2

<h4>Purpose</h4>The co-stimulatory molecules CD80 and CD86 are upregulated on activated antigen-presenting cells (APC). We investigated whether local APC activation, induced by subcutaneous (s.c.) inoculation of lipopolysaccharides (LPS), can be imaged by positron emission tomography (PET) with CD80/CD86-targeting <sup>64</sup>Cu-labelled abatacept.<h4>Procedures</h4>Mice were inoculated s.c. with extracellular-matrix gel containing either LPS or vehicle (PBS). Immune cell populations were analy ...[more]

PMID: 32989622

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Dataset Information

In Vivo Imaging of Local Inflammation: Monitoring LPS-Induced CD80/CD86 Upregulation by PET.

Purpose

Procedures

Results

Conclusions

Publications

In Vivo Imaging of Local Inflammation: Monitoring LPS-Induced CD80/CD86 Upregulation by PET.

Similar Datasets

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