將干細胞注射到發(fā)育中的胎兒聽起來好像有點危險,,但是卻能夠延長患有脆骨病兒童的生命,。
來自倫敦皇家學院的Nicholas Fisk和同事對人類III型脆骨病(brittle bone disease)或成骨不全癥小鼠模型進行了研究,。這種能夠能通過DNA檢測或超聲波進行診斷的遺傳缺陷會破壞膠原質(zhì)的產(chǎn)生,,從而導致骨骼脆弱和生長遲緩。
Fisk的研究組將人類胚胎間充質(zhì)干細胞通過子宮壁注射到14天大的小鼠胚胎中,。在三個月大時,,與未處理小鼠相比,,處理小鼠的長骨骨折只有對照的三分之一。而且,,它們的骨骼還更強壯、腿骨更長,。
盡管目前已經(jīng)有藥物能夠治療這種疾病,,但是干細胞移植則可能具有更多的益處,例如肢體骨骼長度的增加,。事實上,,這種治療方法在美國也有嘗試。Fisk在上周的國際干細胞研究協(xié)會年會上公布了這些結(jié)果,。
“成骨不全”又稱脆骨病,,是一種遺傳性疾病,屬于先天性結(jié)締組織缺陷,,以前分為先天型和遲發(fā)型兩種類型,,現(xiàn)分為I、II,、III,、IV四種類型。脆骨病主要是因膠原蛋白(collagen)量不足與質(zhì)的缺陷導致的,。在骨胳系統(tǒng)導致骨溶解吸收過速,,造成骨質(zhì)疏松而易骨折,骨胳強度耐受力變差而容易脆弱骨折的疾病,。
這種疾病因膠原蛋白基因突變的不同,,而則造成不同的臨床癥狀。由輕微的骨質(zhì)疏松表現(xiàn)至骨折頻繁,,甚至在子宮內(nèi)胎兒階段即產(chǎn)生骨折,,最嚴重的造成在嬰兒出生不久后就夭折,甚至造成死產(chǎn),。
原始出處:
Stem cells toughen up fetus's brittle bones
04 June 2007
NewScientist.com news service
Injecting stem cells into a developing fetus might sound risky, but it could prolong the lives of children with brittle bone disease.
Nicholas Fisk and colleagues at Imperial College London studied mouse models of human type III brittle bone disease, or osteogenesis imperfecta (OI). The genetic defect - detected in human fetuses by DNA testing or ultrasound - disrupts collagen production, leading to weak bones and stunted growth. Those with type III OI suffer fractures while in the womb and rarely survive beyond early adulthood.
Fisk's team injected human fetal mesenchymal stem cells through the wall of the uterus into 14-day mouse fetuses. At the age of 3 months, treated mice had suffered just one-third of the long-bone fractures compared with untreated mice. Their bones were also stronger and their leg bones longer.
While drugs exist to treat the disease, stem cell transplants seem to have extra benefits, such as this boost in limb length, says Fisk. In fact, the treatment has already been tried in the US on three children with OI whilst still in the womb, with promising early results seen after the babies were born. Fisk, who last week presented the work at the annual meeting of the International Society for Stem Cell Research in Cairns, Australia, believes the treatment should now be offered on a case-by-case basis. Other experts caution, however, that a full clinical trial in people is needed first.
From issue 2610 of New Scientist magazine, 04 June 2007, page 20