新型细胞追踪法可确定干细胞移植是否成功
2013/07/16
美国斯坦福大学的科学家们研发了一种新型非侵入性干细胞追踪法,用铁补充剂追踪干细胞。这项新技术未来可以应用于,在提取患者自身的骨髓间充质干细胞移植到膝盖关节损伤部位治疗后,帮助医生确定干细胞移植手术是否成功。


美国斯坦福大学的科学家们研发了一种新型非侵入性干细胞追踪法,用铁补充剂追踪干细胞。这项新技术未来可以应用于,在提取患者自身的骨髓间充质干细胞移植到膝盖关节损伤部位治疗后,帮助医生确定干细胞移植手术是否成功。这项研究成果发表在Radiology杂志上。

该研究的之前的研究对象是啮齿类动物。今年秋天,科学家计划开展人类临床试验,提取患者自身的骨髓间充质干细胞移植到膝盖关节损伤部位治疗。 骨髓间充质干细胞可以分化为骨骼、软骨、肌肉、脂肪和肌腱,但是不能分化为其他类型的细胞。

该研究报告的作者之一,同时开展放射学研究和临床治疗工作的Heike Daldrup-Link博士说,每年门诊接诊关节炎患者的人数高达4400万,其中需要进行膝关节置换的达70万。针对处于发病初期的年轻患者,如果及时进行受损软骨修复术可能会防止病情进一步恶化,未来生活中也不用担心需要进行膝关节置换。

虽然利用间充质干细胞修复受损的软骨组织这项研究已经取得了一定的进展。“但是在整个过程中可能会出现很多问题:移植的干细胞可能会死亡;它们可能会迁移到其他部位;它们还可能会分化为软骨以外的其它组织,比如说疤痕组织” 斯坦福大学分子成像计划组成员之一Heike Daldrup-Link说道。

由此看来,对移植到患者膝关节部位的干细胞进行追踪是很有必要的。随着该干细胞追踪技术的应用,利用磁共振成像可以很直观的观察手术几个星期以后干细胞的情况。这可以给骨科医生提供信息帮助他们判断手术是否成功。

干细胞移植过程是:首先标记的间充质干细胞与造影剂共同孵育后,然后转移到离心机中离心,最后将冲洗过的干细胞移植到患者体内。这个过程涉及对骨髓中的干细胞进行标记。所以,在从大鼠骨髓提取干细胞之前,项目负责人Aman Khurana博士和Fanny Chapelin副研究员将纳米氧化铁(一种美国食品药品管理局认证许可的由氧化铁纳米粒子组成的,用来治疗贫血的铁补充剂)注射到大鼠的骨髓中。当该物质充分进入间充质干细胞后,研究人员提取细胞将其注入大鼠膝关节受损部位。四个星期以后,他们对细胞的核磁共振信号进行检测。

Heike Daldrup-Link和其他研究人员曾经在体外实验中使用纳米氧化铁作为标记物对干细胞进行标记,发现间充质干细胞很少吸收这种物质。但是有趣的是,这次的研究结果表明,在体内,间充质干细胞大量吸收这种物质。即便是在几个星期以后,移植到大鼠膝关节受伤部位的间充质干细胞含有大量的铁元素,可以检测到很强的核磁共振信号。

Heike Daldrup-Link博士表示,在实验室中对细胞进行标记可能会导致细胞污染,这项新技术的细胞标记过程是在体内进行的,所以可以降低细胞污染的风险。另外,还可以从关节炎患者自身提取骨髓间充质干细胞移植到其受损的膝关节部位进行治疗。

这项技术将患者自身的细胞从一个部位移植到另外一个部位,在干细胞自体移植方面是一个巨大的突破。矫形外科专家Jason Dragoo副教授计划进行一项临床试验,提取患者自身的骨髓间充质干细胞移植到膝盖关节损伤部位治疗。

Heike Daldrup-Link说,这项新技术的亮点就在于发现了一个事实,铁补充剂可以用来追踪干细胞。

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