PMC

TAR of animals injected with active Cy5.5-annexin V. Animals were CPA-treated or had no CPA treatment. Each animal contained CPAsensitive LLC and CPA-resistant CR-LLC carcinoma, as shown in . Values are means and standard deviations with four animals per group.

Competition assay for the ability of Cy5.-annexin V conjugates to bind PS on the surface of camptothecin-treated Jurkat T cells. Displacement of FITC-annexin V (FACSFL1 channel) with a 10-fold excess of Cy5.5-annexin V preparations labeled with increasing numbers of Cy5.5 dyes per mole of protein. As n decreases (back to front), Cy5.5-annexin Vs become more effective inhibitors of FITC-annexin V binding.

In vivo imaging of LLC implanted in the mammary fat pads of nude mice. LLC indicates CPA-sensitive and CR-LLC indicates CPA-resistant tumor. (A) White light image 90 minutes after injection of active annexin V. (B) Raw NIRF image of (A). (C) Color-coded map of NIRF intensity superimposed on the white light image. (D) Raw image of tumors after CPA treatment and injection of inactive Cy annexin V. (E) TUNEL stain of the LLC tumor. (F) TUNEL stain of the CR-LLC tumor.

Labeling of untreated and camptothecin-treated Jurkat T cells with active Cy5.5-annexin V. (A) Untreated cells incubated with active Cy-annexin V and FITC-annexin V. The FL1 channel is for fluorescein whereas FL4 is for Cy5.5. Unlabeled cells are in the left quadrant (91.8%), whereas cells labeled with both annexin Vs are in the upper right quadrant (7.2%). (B) Camptothecin-treated cells incubated with active Cy-annexin V and FITC-annexin V. Double-labeled cells are in the upper right quadrant (59.1%), with unlabeled cells in the lower left quadrant (36.7%). (C) Fluorescence micrographs of camptothecin-treated cells stained with active Cy-annexin V and the caspase probe FITC-VAD-FMK. A membrane-bound NIRF signal from active Cy-annexin V and a cytoplasmic green fluorescence from FITC-VAD-FMK are seen.