Monash research could lead to new thymus growth

Scientists at Monash University have identified a population of epithelial cells in the thymus they hope will be able to regenerate and regrow the tiny immune system organ.

The thymus is a crucial part of the immune system - it provides the environment for haematopoietic stem cells to develop into T cells. The thymic epithelial cells play an important role in educating T cells to discriminate between self and non-self - so that they can act against foreign antigens and infected cells, but ignore healthy cells and tissues.

Now PhD student Jason Gill and Assoc Prof Richard Boyd at the Monash University Medical School have successfully isolated a population of thymic epithelial cells in mice that contains stem cells capable of regenerating the thymus.

"The discovery of thymic epithelial stem cells is hugely exciting for us and has taken 15 years of dedicated research," said Boyd.

Gill explained that the current research has demonstrated the presence of the population in mice, and said that they were now looking for the equivalent human population containing thymic epithelial stem cells.

"We're confident that the population exists from studies on intracellular markers, but we need to identify the homologous human marker. We're very confident that a similar glycoprotein will be found," he said.

According to Boyd, the thymic epithelial stem cells would have uses in regenerating the thymus in patients who have damaged thymuses due to disease or ageing.

"There has been limited success with thymus transplants as they are invariably rejected by the recipient, but now we have the possibility of rebuilding someone's thymus after it has been destroyed or using gene therapy to correct gene mutations that lead to thymus problems," Boyd explained.

The research was published in the June 17 issue of prestigious journal Nature Immunology.

Melbourne drug discovery company Norwood Abbey is a research partner of the Monash team. In a statement, the company said the discovery "significantly expanded" the opportunities flowing from its sponsored research and licensing agreements with Monash, as well as associated IP.