科學家日前發現不正常的血球可以透過回饋機制(feedback),影響自身的造血幹細胞,藉由改變基因的表現,使幹細胞不斷分裂與分化,修補缺損的血球.
科學家已在動物實驗中發現,轉錄因子Myb會抑制血小板產生,當失去此基因時,血小板會大量生產,此時不成熟的血小板會藉由訊息傳遞影響自身的造血幹細胞,以維持血小板的含量.
身體的幹細胞並非處於休息的狀態,會受到周邊血液血球生長情形而有所影響,進而調控自身的分裂與分化能力.
The discovery of a blood cell 'feedback loop' in the body opens up new avenues of research into diseases caused by stem cell disorders, and the potential for new disease treatments.
"We know that blood stem cells give rise to all the mature blood cells, but the standard assumption was that external factors control blood cell production and the two populations exist in isolation.
"This study shows that the mature cells actually communicate back to the stem cells, changing their gene expression and influencing their behaviour," he said.
In fact, in their research, the scientists made the discovery while studying the effect of the loss of Myb, a transcription factor that represses platelet production, in animal models.
Team member Dr Carolyn de Graaf said that the loss of the Myb gene meant the animals had very high numbers of platelets in their blood, which caused changes in the signalling pathways that control stem cell maintenance.
"The stem cells, rather than being maintained in a 'resting state' until needed, were being told to continually cycle and produce mature blood cells. The stem cells were eventually exhausted and blood disorders developed because there were not enough stem cells to produce new red and white blood cells," he said.
Read more: http://www.medindia.net/news/Mature-Blood-Stem-Cells-can-Communicate-With-Their-Stem-Cell-Parents-77460-1.htm#ixzz16uy1Zk7c
