Summary

This recently published study is the first demonstration of DC exosome-based therapy for a degenerative alveolar bone disease and provides the basis for a novel treatment strategy.

Periodontitis (PD) is a chronic bone disease that affects over 50% of the U.S. population. Severe PD lesions are infiltrated with B cells, macrophages, and dendritic cell (DC) clusters with CD4+T cells. The immune response can be shaped based on the maturation status of DCs, yet no effective immunomodulatory agent for PD has been identified. The goal of the current study was to characterize the immunobiology of DC derived exosome subtypes in vitro and in vivo and their ability to reprogram immune cells responsible for inflammatory bone loss.

The authors have used nanoScan SPECT/CT for imaging of exosome biodistribution in the murine periodontitis model.

Results from nanoScan SPECT/CT

Locally administrated exosomes showed higher affinity and slower clearance from periodontal tissues in the inflammatory, alveolar bone loss model. (A) SPECT CT live animal in vivo imaging of free, In-111 (left) or In-111-labelled, exosomes (right) in mice after the 24h IV administration. (B) Local delivery of free, In-111 (left) or In-111-labelled, exosomes (right) by injection in the palatal gingiva at the right side of maxilla was utilized. (C) Radioactivity in maxilla, relative to the total, when free or bound to DC EXO, was expressed as a percentage determined by using SPECT CT images. (D) Radioactivity in maxilla, relative to the total, when free or bound to DC EXO, was expressed as a percentage, in post-mortem isolated maxilla, determined by a gamma counter. Mice were subjected to ligature placement to induce inflammatory bone loss prior to imaging. Yellow arrows delineate maxilla, white arrows liver, spleen and other non-oral sites.

Publication: https://onlinelibrary.wiley.com/doi/10.1080/20013078.2020.1795362