Normally, the liver and kidneys produce a tiny hormone called thrombopoietin which binds to hematopoietic cell receptors.

正常情况下，肝脏和肾脏会合成一种叫做促血小板生成素的激素，可以与造血细胞受体结合。

Hematopoiesis starts with a multipotent hematopoietic stem cell which can develop into various cell types - it's future is undecided.

造血开始于多能造血干细胞，它可以分化成不同种类的细胞，未来不可限量！

Other stem cells are multipotent and differentiate into a variety of cell types (ie, hematopoietic stem cells).

其他干细胞是多能的并且分化成多种细胞类型（如造血干细胞）。

Now, the vast majority of bone marrow is made of hematopoietic cells which are the early progenitor cells that can differentiate into other cell types.

大部分骨髓由造血细胞形成；造血细胞是可以分化为其他类型细胞的原始细胞。