Off-Target and Tumor-Specific Accumulation of Monocytes, Macrophages and Myeloid-Derived Suppressor Cells after Systemic Injection

Publication type: 
Article
Author(s): 
Francis COMBES et al.
Citation: 

Combes, F. et al. (2018) Off-Target and Tumor-Specific Accumulation of Monocytes, Macrophages and Myeloid-Derived Suppressor Cells after Systemic Injection.  Neoplasia vol 20 (8) pp. 848-856.

Description: 

Solid tumors frequently coexist with a degree of local chronic inflammation. Recruited myeloid cells can therefore be considered as interesting vehicles for tumor-targeted delivery of therapeutic agents. Using in vivo imaging, the short-term accumulation of systemically injected  monocytes, macrophages and myeloid-derived suppressor cells (MDSCs) was compared in mice bearing fat pad mammary carcinomas. Monocytes and macrophages demonstrated almost identical in vivo and ex vivo distribution patterns with maximal tumor-associated accumulation seen 48 hours after injection that remained stable over the 4-day follow-up period. However, a substantial accumulation of both cell types was also seen in the liver, spleen and lungs albeit decreasing over time in all three locations. The MDSCs exhibited a similar distribution pattern as the monocytes and macrophages, but demonstrated a better relative on-target fraction over time. Overall, our findings highlight off-target cell accumulation as a major obstacle in the use of myeloid cells as vehicles for therapeutic tumor-targeted agents and indicate that their short-term on-target accumulation is mainly of nonspecific nature.

Year of publication : 
2018
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Magazine published in: 
Neoplasia