Researchers presenting at the European Society of Human Reproduction and Embryology (ESHRE) demonstrate how they -for the first time – isolated and grew human follicles to a point of “biofunctionality” on a bioengineered ovarian scaffold made of “decellurised” ovarian tissue.
Prof Adam Balen, Professor of Reproductive Medicine and Surgery, Leeds Fertility, Seacroft Hospital, Leeds, said:
“This is an extremely important advance in the field of fertility preservation. The current options available to women who are faced with the prospect of sterilising chemotherapy are either egg freezing (the eggs are taken after a course of ovarian stimulation drugs as with IVF treatment) or ovarian tissue cryopreservation (usually a whole ovary is removed by laparoscopic surgery) – the latter is the only option for pre-pubertal girls.
“In this ground breaking study, the authors have used a decellurised ovarian scaffold on which to grow egg-containing follicles taken from the ovary before a woman receives sterilising treatment for cancer. The ability to successfully create a “new ovary” by removing any tissue that might potentially re-introduce the cancer and fashioning a scaffold on which to grow the egg-containing follicles, allows the reimplantation of a “safe” ovary, with the potential to successfully restore fertility. This is a “proof of concept” study, and it used human tissue transplanted into mice to show the graft could work, so it is still yet to be put into clinical practice but it certainly holds much promise for the future.”
Prof Ying Cheong, Professor of Reproductive Medicine, University of Southampton, and Clinical Director, Complete Fertility, Southampton, said
“This is an important proof of concept study representing early data that ovarian follicles can be separated from the rest of the ovarian cells and be regrown in a scaffold. This has the potential to eliminate risk of reimplanting cancer cells into patients who wish to freeze ovarian tissue for fertility preservation. However, there are still many unknowns.
“Importantly, we don’t yet know the quality of these eggs grown within these follicles. Fundamental ovarian biology suggests eggs within follicles interact intricately with their surrounding environment and ovarian cells. Follicles grown where these supporting cells are stripped off may be deprived developmentally. Longer term in vitro and in vivo experiments are required before this can be translated to human use.”
Dr Raj Mathur, Consultant and Clinical Lead for Reproductive Medicine, Manchester NHS Foundation Trust, and Secretary of the British Fertility Society, said:
“This is an interesting proof-of-concept study using human tissue in a laboratory setting. It opens the door to further research in developing ‘bio-engineered’ ovaries for fertility preservation. At present however the concept is not ready for use in patients and I expect it will be several years before we see trials in patients.”
Prof Daniel Brison, Honorary Professor of Clinical Embryology and Stem Cell Biology, and Scientific Director of the Department of Reproductive Medicine, University of Manchester, said:
“This is a very interesting and novel experimental approach by one of the leading centres in the world working in fertility preservation for women with cancer. The use of decellularised scaffolds is common in regenerative medicine, as they can provide a structure for the growth and differentiation of tissues derived from stem cells allowing transplantation back into patients.
“I can see that this approach might well work with the ovary, although it is not possible to tell until the data from this research group have been peer reviewed by the scientific community and published in a scientific journal.
“The immediate application of this research is likely to be limited to women who are at risk of having malignant cells in their preserved ovarian tissue, since using this new technique only the eggs and surrounding cells of the follicle would be transplanted back. This could give rise to a problem in itself however, as the surrounding ovarian cells left behind might be required for the ovary to function fully.”
Prof Richard Anderson, Head of Section of Obstetrics and Gynaecology, MRC Centre for Reproductive Health, University of Edinburgh, said:
“Our understanding of the development of the human egg has been limited by many difficulties, including a good model with which to study it in the lab. An artificial ovary that supports close to normal development of the follicle and the egg within it would be very valuable scientifically, helping develop new tests and perhaps treatments for infertility, and it would also be valuable for women where ovarian tissue has been stored prior to cancer treatment, but is at risk of containing cancer cells so can’t be replaced.
“This study builds on work by others who have developed a mouse artificial ovary and is a step towards making an ovary that can support the growth of human ovarian follicles. It did however involve transplant of the artificial ovary into a mouse which will need to be avoided for future clinical use. At this stage many questions remain, including how far it can support follicle and egg development, but it is certainly a promising approach.”
* Abstract title: ‘Towards an artificial ovary: Grafting preantral follicles on decellularized human ovarian tissue’ by S. Pors et al. This is a conference talk that will be discussed at the European Society of Human Reproduction and Embryology (ESHRE) conference 2018 in Barcelona. There is no paper as this is not published work.
Declared interests
Prof Adam Balen: “No conflicts.”
Prof Richard Anderson: “No conflict of interest.”
Prof Daniel Brison: “I supervise PhD students and receive academic grant funding from NIHR and MRC in the general area of fertility research including human embryo development. I have no commercial interests.”
None others received.