Developing cell-free regenerative medicines

Lead researcher

Dr Rebecca Lim

Main finding

We found that amnion epithelial cells shed minuscule particles, called exosomes, as part of their mechanism of repair during lung fibrosis (scarring). We were able to collect these particles and administer them as an inhaled treatment to preclinical models with experimental lung fibrosis. We showed that this inhaled form of regenerative medicine was effective in reversing lung fibrosis even in aged mice, which have an impaired repair response. This was in part achieved by activating the aged, sluggish lung stem cells and by quietening down the otherwise overwhelming lung inflammation.


The Ritchie Centre

Research group

Amnion Cell Biology Group


Dr Jean Tan, Ms Sinnee Lau, Dr Bryan Leaw, Dr Hong Ngyuen, Prof Lois Salamonsen, Mr Mohamed Saad, Ms Siow Teng Chan, Dr Mirja Krause, Prof Carla Kim, Prof William Sievert, Prof Euan Wallace

Journal and article title

Most surprising

We were surprised to find that the exosomes from amnion epithelial cells were able to directly influence lung stem cells and specific types of the immune system that have been previously shown to play valuable roles in lung repair. The exosomes were stable for months when stored in a frozen form. They do not require special freezing methods or chemicals to keep them stable.

Future implications

These findings suggest that a cell-free form of regenerative medicine can be developed for chronic conditions such as lung fibrosis. Inhaled formulations such as what was used in this study would mean that patients would not need intravenous injections of cells. The knock-on effect of this is the reduction in costs of running clinical trials, and if/when these therapies are approved for widespread use, it would mean that patient could administer the treatments themselves, such as when using an inhaler or nasal spray. The exosomes are cheaper to produce compared to living cells with less variability, so this may mean that exosome-based therapies could be more accessible to patients.

Disease/health impact

Idiopathic pulmonary fibrosis

Associate Professor Rebecca Lim, 2017 NHMRC Grant success