Journal of Nanomedicine & Nanotechnology

A new fluorescence/PET probe for intracellular human telomerase reverse transcriptase (hTERT) using Tat peptide-conjugated IgM antibody

9^th Nano Congress for Next Generation

August 01-02, 2016 Manchester, UK

Kyung Oh Jung

Seoul National University College of Medicine, Korea

Posters & Accepted Abstracts: J Nanomed Nanotechnol

Abstract:

Human Telemorase Reverse Transcriptase, hTERT, is expressed in most cancer cells, and considered as an important tumor biomarker. However, targeting hTERT is difficult due to its cellular location. We developed a new dual probe for optical and nuclear imaging to visualize intracellular hTERT proteins using Tat peptide-conjugated IgM antibody. Monoclonal IgM antibodies for hTERT were conjugated with the Tat peptide, fluorescence dye (FPR648) and 64Cu-NOTA. HT29 (hTERT+) and U2OS (hTERT-) cells were imaged by confocal microscopy and analyzed by Tissue-FAXS. To visualize nuclear transport of hTERT, tumor cells were irradiated with 4 Gy of ionizing radiation. Tumor xenografts were visualized using Maestro and PETBOX. Cellular penetration was improved by Tat peptide and retention time was prolonged with IgM antibody as compared to IgG antibody. More fluorescence signals were detected in HT29 cells than in U2OS cells after 24 hr. Strong positive fluorescence signals were observed in 78.54% of total HT29 cells. Interestingly, this probe could visualize nuclear transport of hTERT after irradiation. Fluorescence and PET images of the mice clearly showed higher fluorescence signals and radioactivities in HT29 tumors than in U2OS tumors. In tissues, fluorescence signals were only detected in HT29 tumors. We developed a new fluorescence/PET probe for visualizing the intracellular hTERT using the Tat conjugated antibody which improved cellular penetration. This system can be applied to visualize other intracellular proteins and also can be used to target intracellular biomarkers for therapeutic applications.

Biography :

Kyung Oh Jung has completed his PhD in 2016 from Seoul National University College of Medicine, studying about the concepts of molecular imaging and tumor biology. He is a Post-doctoral fellow from Stanford University School of Medicine from September 2016.

Email: blpg86@snu.ac.kr