The present invention relates to methods of promoting growth of pancreatic islet cells, especially beta islet cells. In particular, the invention relates to methods of promoting growth of pancreatic islet cells by administration of HGF-MET agonists, such as MET agonist antibodies or fragments thereof. The invention further relates to HGF-MET agonists, such as MET agonist antibodies or fragments thereof, and pharmaceutical compositions comprising said agonists, for use in methods of the invention.