雅艾爾:嘿,唐,你能說出你體內(nèi)三種干細(xì)胞的名稱嗎?
Don: I've thought stem cells were from Embryos,Yael, do adult have them, too?
唐:我一直以為干細(xì)胞來自于胚胎,雅艾爾,成人體內(nèi)也有嗎?
Yael: We've got a few kinds of stem cells, each witha different role. The term “potency” is used todescribe the capacity of cells to change, ordifferentiate, into different cell types when theydivide. There are totipotent, pluripotent, multipotent, oligopotent and unipotent cells.
雅艾爾:我們體內(nèi)有一些不同種類的干細(xì)胞,每種都有不同的作用。“效能”這個術(shù)語是用來描述細(xì)胞分裂時,分化成為不同類型細(xì)胞的能力。按“功效”可分為全能性干細(xì)胞、多能性干細(xì)胞、專能性干細(xì)胞和單能性干細(xì)胞。
Don: Wow! How about some examples?
唐:哇!能舉些例子么?
Yael: Sure, a fertilized egg cell as it divides makes every kind of cell in the human body. Thatone cell can create an entire person. So a fertilized egg is an example of totipotency. Embryonicstem cells are almost as flexible. They can differentiate into almost any cell type, like lung,muscle, liver, skin or brain cells. But a single embryonic stem cell can never grow into an entireorganism. This is an example of pluripotency.
雅艾爾:當(dāng)然,人體內(nèi)的一個受精卵細(xì)胞在分裂的時候會產(chǎn)生很多種不同的細(xì)胞。一個細(xì)胞創(chuàng)造了完整的人體。所以受精卵就是一種全能性干細(xì)胞。胚胎干細(xì)胞與之同樣靈活。胚胎干細(xì)胞能夠分化成幾乎所有的細(xì)胞類型,像肺、肌肉、肝臟、皮膚或者腦細(xì)胞。但一個胚胎干細(xì)胞不能長成一個完整的器官。因此它是多能性干細(xì)胞的一個例子。
Don: My friend had a Stem Cell Transplants as a treatment for leukemia. What kind of stemcells of those?
唐:我的朋友在治療白血病的時候接受了干細(xì)胞移植,這又是哪一種干細(xì)胞呢?
Yael: She probably received a donation of blood stem cells, like those found in bone marrow.Blood stem cells are multipotent. They can make all the different blood cell types, like red andwhite blood cells or platelets. But they can't create other kinds of cells. An example ofoligopotency lurks in your lymph nodes. Lymphoid stem cells can produce a few, but not all,kinds of blood cells. Finally, cells that only produce identical copies of themselves are calledunipotent. Like skin cells, when they divide, they only make more skin cells.
雅艾爾:她可能接受的是骨髓中的造血干細(xì)胞。造血干細(xì)胞是多能性干細(xì)胞,它們可以生產(chǎn)各種類型的血細(xì)胞,例如紅細(xì)胞、白細(xì)胞或者血小板。但是不能生產(chǎn)其他種類的細(xì)胞。專能性干細(xì)胞的一個例子潛伏在你的淋巴結(jié)里。淋巴干細(xì)胞能制造一些、但非全部的血細(xì)胞。最后,只能復(fù)制自己的干細(xì)胞被稱為單能性干細(xì)胞,例如表皮細(xì)胞,這些細(xì)胞再分裂時只能形成表皮細(xì)胞。