Centre for Bio discovery and Molecular Development of Therapeutics, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, Queensland, Australia
Granulins are a family of protein-based growth factors that are involved in a wide range of physiological functions and disease processes from inflammation to tumour growth. The liver-fluke granulin, Ov-GRN-1, isolated from a carcinogenic liver fluke Opisthorchis viverrini, has been recently shown to induce angiogenesis and significantly accelerate wound repair in vivo and in vitro. Therefore, Ov-GRN-1 offers potential as a novel biologic tool for treating acute and chronic wounds where the normal tissue repair mechanisms are overwhelmed, such as diabetic ulcers. We are studying the structure-function relationships of Ov-GRN-1 with the aim of engineering more stable, potent that are cheaper to manufacture while the bioactivity still maintained. To determine the minimal optimized fragment of Ov-GRN-1, analogues were synthesised using solid phase peptide synthesis with FMOC chemistry. The peptides were purified with RP-HPLC and characterised using mass spectrometry. Structural analysis was done using NMR spectroscopy and biological activity examined using real-time cell proliferation monitoring using an xCELLigence unit and in vitro Scratch wound healing assay. The most active peptides in the cell-based assays were tested in an in vivo wound-healing assay. The data showed that it is feasible to minimise the Ov-GRN-1 protein and maintain bioactivity.