干细胞移植物

A stem cell transplant is a procedure that replaces defective or damaged cells in patients whose normal blood cells have been affected by cancer. Stem cell transplants commonly are used to treat leukemia and lymphoma, cancers that affect the blood and lymphatic system. They also can help patients recover from or better tolerate cancer treatment.

In addition, these stem cell transplants are used to treat hereditary blood disorders, such as sickle cell anemia, and autoimmune diseases, such as multiple sclerosis.

干细胞移植用造血干细胞使用造血干细胞。这些未成熟的细胞在骨髓中开始寿命，最终发展到各种类型的成熟血细胞中，包括：

• 红细胞，携带氧气。
• 血小板，帮助血液凝块。
• 白血细胞，有助于抗击感染。

有两种类型的干细胞移植：

自体干细胞移植

在化疗之前，从患者自己的骨髓收获细胞，并在癌症治疗后被替换。这些通常用于治疗淋巴瘤和骨髓瘤等疾病。他们几乎没有拒绝的风险graft versus host disease(GVHD) and are therefore safer than allogeneic transplants.

Allogeneic stem cell transplant

干细胞来自一个组织最clo的捐赠者sely matches the patient. These cells can also come from umbilical cord blood extracted from the placenta after birth and saved in special cord blood banks for future use.MD安德森's脐带血银行积极寻求脐带的捐赠。

同种异体移植通常用于治疗涉及骨髓，例如白血病的疾病。与自体移植不同，它们产生新的免疫系统对抗癌症的反应。他们的缺点是拒绝或GVHD的风险增加。

发现干细胞供体

干细胞移植患者通过人白细胞抗原（HLA）打字与合格的供体相匹配。HLA是存在于体内大多数细胞表面上的蛋白质。HLA标记有助于身体区分来自外部细胞，例如癌细胞的正常细胞。

HLA键入是用患者血液样本完成的，然后将其与来自家庭成员或捐助者登记处的样品进行比较。它有时可能需要几周或更长时间才能找到合适的捐助者。

The closest possible match between the HLA markers of the donor and the patient reduces the risk of the body rejecting the new stem cells (graft versus host disease).

最好的比赛通常是第一学位相对（儿童，兄弟姐妹或父母）。这些可以是满匹配或半匹配的相关移植，也称为haploidenticaL.移植。However, about 75% of patients do not have a suitable donor in their family and require cells from matched unrelated donors (MUD), who are located through registries such as theNational Marrow Donor Program。

干细胞移植副作用

Because the patient’s immune system is wiped out before a stem cell transplant, it takes about six months to a year for the immune system to recover and start producing healthy new blood cells. Transplant patients are at increased risk for infections during this time, and must take precautions. Other side effects include:

• Graft versus host disease (GVHD): This condition occurs when the body’s immune cells attack cells from the donor, or when the donor cells attack your cells. GVHD can occur right after the transplant or more than a year later.
• 增加出血的风险
• Anemia: Some patients may require a blood transfusion to treat persistent low red blood cell counts.
• 疲劳
• 嘴疮