Fresh advances are being made in stem cell research at the University of Tampere

Stem cells from fat tissue can be used to grow jawbones.  Photograph: Jonne Renvall

Stem cells from fat tissue can be used to grow jawbones. Photograph: Jonne Renvall

Susanna Miettinen

Susanna Miettinen

The University of Tampere is conducting pioneering research on stem cells. The Human Spare Parts project – a joint venture of the University of Tampere and Tampere University of Technology – is being conducted at the universities’ joint research institute, BioMediTech.

The project, which includes research groups focusing on bone, ophthalmological, neural and cardiac applications, has already been ongoing at the University of Tampere for several years. In addition to bone applications, Associate Professor Susanna Miettinen’s research group is also responsible for studies on the treatment of incontinence.

“Such problems are surprisingly common in young women after delivery, for example. We want to develop treatments where stem cells are obtained from other donors. Such cells are called allogeneic stem cells,” Miettinen explains.

Twenty researchers work in Miettinen’s research group, and in total, about one hundred researchers are working on stem cell and tissue engineering at BioMediTech.

Fat tissue is a rich source of stem cells

There are two kinds of stem cells in humans: embryonic and adult stem cells. Whereas the former can only be obtained from embryos, the latter are found in the functional tissue of both children and adults.
With current technology, stem cells can be found around the human body. Fat tissue – also known as adipose tissue – is the best place to look for stem cells. The so-called mesenchymal stem cells found in adipose tissue produce new fat cells, but under the right conditions, they can also differentiate into bone, cartilage and muscle cells.

“Our work is based on the differentiation potential of stem cells. The stem cell is able to regenerate as a stem cell, but it can also differentiate into another cell type. We are studying both of these properties,” Miettinen says.

Stem cells are found in greater number in adipose tissue compared to bone marrow, for example, and the collection of stem cells from fatty tissue is also easier, as the cells can be collected using liposuction.

“The cells also secrete many useful molecules. For instance, adipose stem cells release many molecules that contribute to the growth of vessels. They are a kind of medicine store whose contents are launched into a diseased area,” Miettinen explains.

Over the last ten years, the Regea Cell and Tissue Center at the University of Tampere has produced dozens of stem cell products from adipose tissue. Although stem cells from adipose tissue cannot yet be commercially utilised in Finland, they can be used to treat patients with the permission of Fimea, the Finnish Medicines Agency.

“We give the human body its own tools to grow new bone. However, it is a very complicated procedure. For example, the area to be treated must have sufficient blood circulation. The plan is to conduct the next treatment on a patient early next year,” Miettinen says.

Various kinds of stem cells

Pluripotent stem cells are used in ophthalmological, neural and heart applications because they can differentiate into many different cell types.

“Pluripotent stem cells are very versatile. They can be obtained either from embryos or directly from patients. A skin biopsy is taken from the patient, and the skin cells are isolated using special laboratory methods that make the cells behave like embryonic stem cells,” Miettinen explains.

A limited number of other cell types can be made from mesenchymal stem cells. Unipotent stem cells, on the other hand, only differentiate into one type of tissue.

In clinical use, it is possible to conduct autologous stem-cell transplantation where the cells are isolated from the patient’s own fat tissue, and then differentiated and transferred back into the patient. Another option is to use allogeneic stem cells from donors. This method can be beneficial because it uses stem cells that have already proven to be efficacious. These stem cells can be stored in freezers and used whenever necessary.
Stem cells and biodegradable support materials are combined in treatments. Research groups at the University of Tampere have cooperated with hospitals and used bioactive glass or beta tricalcium phosphate scaffolds as support structures.

Regulation has steadily grown

Regulation concerning stem cell treatments has continuously increased. At the same time, treatments costs have risen.

While having great potential, stem cell therapy is not without risk. There is no guarantee that the stem cells taken from the patient will produce the desired tissue or bone efficiently enough.

“Stem cell use was previously largely based on the physician’s own discretion. There are many stem cell clinics in the world where, for example, stem cells taken from adipose tissue are offered as a panacea for all kinds of ailments. We can only hope that these treatments cause no harm to the patients, because there may be no benefits, either,” Miettinen points out.

Gravely ill patients are often prepared to try all possible treatments, and Miettinen has had to have difficult discussions with such people.

“We are regularly contacted by people who have found one of the shadier stem cell clinics and want to know whether the treatments offered can be trusted. We must obviously caution them that there is no guarantee and there are risks involved. We must be very careful about what we say,” Miettinen explains.

New Centre of Excellence will be launched in 2018

Stem cell research will continue for the foreseeable future at the University of Tampere. Depending on funding decisions, the Human Spare Parts project will end in two years. However, the Centre of Excellence in Body on Chip Research will be launched at the beginning of 2018.

“The range of tissue used will be slightly different than that utilised in the Human Spare Parts project, but in the main, the same techniques will be used in the new project. We are aiming for in vitro modelling, which means modelling cell function in a special tissue culture,” Miettinen says.

Text: Jaakko Kinnunen