Stem cells: the science and the imagination

Human embryonic stem cells were first isolated and grown in culture in 1998. Since then, stem cells have transformed our understanding of human development and disease, replaced animal testing in pre-clinical trials and sparked extraordinary anticipation for the treatment and cure of a wide range of debilitating illnesses. The emerging field of regenerative medicine, in which living cells are used to replenish diseased organs, is based on stem cells.

In such heady times, imagination soars with hope, while clinical practice is grounded by the requirement for safety and efficacy.

Stem cells have the unique dual-capacity of renewal and differentiation. They proliferate indefinitely in controlled conditions, yet they are able to change form and function in response to environmental stimuli. How these changes are regulated is not fully understood.

Embryonic stem cells have the capacity to develop into 200+ types of adult human cells – a condition called totipotency.

Populations of stem cells are found in adults, too, but with a reduced capacity to differentiate – a condition called pluripotency. Recently, it has become possible to induce pluripotency in many different types of adult cells.

In recognition of its excellence in the field, the University of Melbourne and its partners have been awarded $21 million by the Australian Research Council to establish Stem Cells Australia (SCA). SCA is an interdisciplinary collaboration, consisting of a global network of scientific expertise without parallel in cell biology and bioengineering. The aim is to develop cell populations of prescribed function and shape, with a clinical focus on cardiac and neurological diseases.

Four professors from the University of Melbourne are lead figures in SCA: Martin Pera, Trevor Kilpatrick, Doug Hilton (WEHI Director) and David Gardner. Professor Pera, an expert in pluripotency, returns to Melbourne from the USA to direct the organisation.

Professor Gardner, a reproductive biologist and head of the Department of Zoology in the Faculty of Science, played a pivotal role in the development of culture conditions for stem cells in the original 1998 study. The SCA initiative enables his team to refine stem cell culture techniques, so that high-quality populations of cells can be generated. Pure stem cell populations are notoriously difficult to establish and maintain, which has led to some rather hit-and-miss results in the past.

One successful hit has been Mesoblast, a Melbourne-based regenerative medicine company. Mesoblast is a world leader in bringing stem cell technology to the clinic. Professor Silviu Itescu, the founder and CEO of Mesoblast, has been named BioSpectrum Asia’s ‘Man of the Year’ for 2011. His individual honour coincides with Mesoblast being listed in the S&P/ASX 200 Index. Mesoblast is valued at over $2 billion – a value that equates with the entire annual expenditure on R&D by the Australian Government. This is a remarkable achievement for such a young and developmental enterprise. Imagination, it seems, does not soar alone. And medical practice is being transformed.

See: The University of Melbourne Stem Cell Interest Group (UMSCIG) at: www.zoology.unimelb.edu.au/umscig