Scientific background: Receptor-targeted antibody therapies have had huge clinical impact in cancer treatment; new discoveries will result in additional antibody treatments. Imaging antibody biodistribution in cells and in vivo has aided their development.
Mass cytometry, using ICP-MS (inductively coupled plasma mass spectrometry), uses IgG antibodies tagged with metal ions to provide cell-level information on protein expression. LA-ICP-MS (laser ablation ICP-MS) is a relatively new methodology. Laser ablation of a two-dimensional sample, for example a tissue slice, followed by ICP-MS analysis of ablated material, enables highly resolved mapping of elemental distribution. We have recently combined our new chemical technology to tag trastuzumab with metals, and subsequently used metal-tagged trastuzumab with ICP-MS and LA-ICP-MS to map trastuzumab distribution in mice bearing breast cancer tumours (see Figure).
Aims: The overarching objective of this project is to further develop new chemical technology to attach metal tags to antibodies, and using laser-ablation inductively-coupled plasma mass spectrometry (LA-ICP-MS) and inductively-coupled plasma mass spectrometry (ICP-MS), apply this technology to quantify/image:
(i) the biodistribution of antibody-based therapies in vivo in mouse models, and
(ii) quantify the relative distribution of receptor targets in vivo in mouse models.
This will enable high resolution, sensitive and quantitative mapping of both antibody therapies and their target receptors.
Skills: Chemical synthesis, antibody modification and characterisation, tissue culture, in vivo studies in mouse models of cancer, mass spectrometry analysis and imaging, image analysis.
Year 1: Prepare new metal-tagged antibody conjugates targeting receptors of the HER family (EGFR, HER2, HER3 and HER4) implicated in cancer and chemically characterise and test these in vitro.
Year 2: LA-ICP-MS imaging of monolayers of cells treated with new metal-tagged antibody conjugates, and preliminary ICP-MS studies in mouse models of cancer.
Year 3: LA-ICP-MS imaging of tissue from mice administered a combination of new metal-tagged antibody conjugates.