Sickle cell anaemia and thalassaemia are genetic disorders of the red blood cells. People with these disorders suffer painful crises when their damaged blood cells are unable to deliver oxygen properly and may require hundreds of blood transfusions throughout their lives.
These disorders can be diagnosed accurately at around 12 weeks of pregnancy, but until now no treatment has been available. The Nottingham researchers have been studying primitive blood forming cells (stem cells) to determine if they can be used for transplantation into an affected fetus early in pregnancy.
Dr Jones explains, "The major advantage of this approach is that the fetus does not develop a fully competent immune system until after 15 weeks, so even mismatched tissue can be transplanted without rejection occurring. Most importantly, treatment can be offered before any damage has occurred. We have identified stem cells with the capacity to produce, almost exclusively, red blood cells. These stem cells are uniquely suitable for transplantation into a fetus affected with one of these disorders."
There is a very narrow window of opportunity, after diagnosis and before development of the immune system, in which to perform the transplant. Therefore, cells must be ready for immediate use. Dr Jones continues, "We have established a stem cell bank and we have shown that our cells can be stored frozen for up to two years and still retain their ability to engraft, grow and develop after transplant."
The transplant procedure is relatively simple: ultrasound is used to guide a fine needle through the mother's abdomen and into the abdomen of the fetus, where a small volume of cells is injected. Afterwards the pregnancy is monitored in the same way as any other.
The technique, called in utero stem cell transplantation, has been performed in around 30 cases worldwide. There have been some remarkable successes but more research is needed before the procedure becomes widely established.
Notes:
1. Dr Jones will be speaking in the Immune reconstitution following bone marrow
transplantation session on Friday 5 December. The BSI 5th Annual Congress is at
the Brighton Centre, Brighton, UK from 2-5 December.
2. Dr Rhodri Jones can be contacted at the Department of Immunology, University Hospital, Queens Medical Centre, Nottingham NG7 2UH. Tel: +44 115 970 9058 Fax: +44 115 970 9125 D.R.E.Jones@nottingham.ac.uk
3. There will be a press office at the meeting in operation from 9am on Tuesday 2 December. Tel: +44 1 273 724 320 / 0378 406 416 Journalists are welcome to attend but please contact Kirstie Urquhart in advance to register.
4. Before the meeting Kirstie can be contacted on +44 181 875 2402 / kirstie@immunology.org