Tat-functionalized near-infrared emissive polymersomes for dendritic cell labeling.

Journal Article

Dendritic cells (DCs) play a pivotal role in both immune tolerance and the initiation of immunological responses. The ability to track DCs in vivo is imperative for the development of DC-based cellular therapies and to advance our understanding of DC function and pathophysiology. Here, we conjugate a cell permeable peptide, Tat, to near-infrared (NIR) emissive polymersomes in order to enable efficient intracellular delivery for future DC tracking with these optical probes. NIR imaging allows quantitative, repetitive, in vivo detection of fluorophore-laden cells, at centimeter tissue depths without disturbing cellular function. Flow cytometry and confocal microscopy results indicate that Tat-mediated polymersome delivery to DCs is concentration and time dependent, resulting in punctate intracellular localization. Further, loading cells with Tat NIR emissive polymersomes does not interfere with cytokine-induced DC maturation and has modest effects on DC viability, but has a significant effect on mature DC-induced activation of naive T cells. We observe significant uptake of NIR emissive polymersomes when conjugated to the peptide, with a lower detection limit of 5000 labeled DCs. The extent of polymersome delivery is estimated as 70 000 +/- 10 000 vesicles/cell, equivalent to 0.7 +/- 0.1 fmol of NIR fluorophore. Our studies will enable future in vivo tracking of ex vivo labeled DCs by NIR fluorescence based imaging.

Full Text

Duke Authors

Cited Authors

  • Christian, NA; Milone, MC; Ranka, SS; Li, G; Frail, PR; Davis, KP; Bates, FS; Therien, MJ; Ghoroghchian, PP; June, CH; Hammer, DA

Published Date

  • January 1, 2007

Published In

Volume / Issue

  • 18 / 1

Start / End Page

  • 31 - 40

PubMed ID

  • 17226955

International Standard Serial Number (ISSN)

  • 1043-1802

Digital Object Identifier (DOI)

  • 10.1021/bc0601267

Language

  • eng

Conference Location

  • United States