Researchers found unusually high levels of maternal DNA in the blood of around 20% of children with Type 1 diabetes.
These maternal stem cells also seemed to help in producing insulin, which is not synthesized in children with Type 1 diabetes and even help to restore damaged tissue in the pancreas. They also found that the maternal cells were not targeted by the child's immune system.
During pregnancy, stem cells of mother and baby may get exchanged and these cells are found to be tolerated by the new host and live on for many years, a phenomenon called Microchimerism. It is still not clear whether the presence of such cells harm the recipient.
Researcher Professor Edwin Gale said: 'Our initial theory was that perhaps, in some situations, too many cells cross from mother to foetus in pregnancy.'
Earlier it was thought that probably the child loses tolerance to the half-foreign cells of the mother and develops diabetes as a result. But the current research disproves this.
Dr Lee Nelson, a co-researcher said, 'The findings raise the possibility that a mother's stem cells might be harvested, and used to treat her diabetic child.'
These cells would be better than those taken from an unrelated donor, as it would be completely genetically mismatched.
Dr Nelson said: 'The child is probably tolerant to the mother's half-matched cells because the child acquired the cells during its life as a foetus while its immune system was still developing.'
'If cells with the potential to produce insulin can pass from mother to child during pregnancy, without the child's immune system destroying them as seems to be the case here, then this could open up promising new avenues of research, and perhaps provide a new source of insulin-producing cells for therapeutic use.'