They used strong chemicals to remove the donor’s cells, leaving a tissue scaffold.

它们使用强烈的化学制品把这段气管中原捐赠者的细胞完全清除，只剩下气管的组织架构。

It happens when the immune system generated by the donor cells attacks the patient's organs.

这种病症会让由供体细胞生成的免疫系统攻击患者的器官。

In both cases, the donors' stem cells immediately began to attack the patients' immune cells.

在两起病例中，捐献者的干细胞很快就开始攻击患者的免疫细胞。

But even if a patient avoids graft-versus-host disease, their immune system may reject the donor cells.

然而即使患者躲过了移植物抗宿主病，他们的免疫系统还是有可能排斥供体细胞。

Then the donor cells are infused into the patient's body through a central line.

接下来，供者的细胞将通过静脉注射输注给患者。

But if the donor cells are the same blood type as the recipient's cells, the donor cells won't be flagged for destruction, and won't form clumps.

但是当献血者的血型与受血者的血型相同时，献血者的血细胞就不会被标记为待摧毁，也不会形成血块。

If these regions are similar in the donor and the recipient, the recipient's immune system is more likely to accept the donor cells.

如果供者和受者的这些区域比较相似，受者的免疫系统就更有可能接受供者的细胞。

But if the donor cells are the same blood type as the recipient’s cells, the donor cells won’t be flagged for destruction, and won’t form clumps.

但是，如果供体细胞与受体细胞的血型相同，则供体细胞不会被标记为需要销毁， 也不会形成团块。

This life-threatening condition occurs in about 30–50% of patients who receive donor cells from anyone other than an identical twin, particularly when the stem cells are collected from the blood as opposed to the bone marrow.

这种危机生命的病症会发生在约 30% - 50% 那些没有从同卵双胞胎获得供体细胞的患者身上，尤其是在干细胞是从血液中而不是从骨髓中采集的情况下。