Namen A E, Schmierer A E, March C J, Overell R W, Park L S, Urdal D L, Mochizuki D Y
Immunex Corporation, Seattle, Washington 98101.
J Exp Med. 1988 Mar 1;167(3):988-1002. doi: 10.1084/jem.167.3.988.
We have used a biological assay system we developed to biochemically purify a previously uncharacterized murine lymphopoietic growth factor designated lymphopoietin 1 (LP-1). This factor is capable of stimulating the proliferation and extended maintenance of precursor cells of the B lineage. A stromal cell line producing LP-1 was established after transfection of primary stromal cultures with a plasmid encoding the transforming genes of SV40. This factor was purified to a single 25-kD species from the culture supernatant of an adherent stromal cell line. This material acts on immature lymphocytes, it binds to specific receptors on cells, and is distinct from previously described hematopoietic factors. LP-1 has been purified some 10(7)-fold with an overall recovery of 35%. The purified protein exhibits a specific activity of approximately 4 X 10(6) U/micrograms of protein and is active at a half-maximal concentration of 10(-13) M.
我们使用自行开发的生物测定系统，对一种先前未被鉴定的小鼠淋巴细胞生成生长因子——淋巴细胞生成素1（LP-1）进行了生化纯化。该因子能够刺激B淋巴细胞系前体细胞的增殖并使其长期维持。在用编码SV40转化基因的质粒转染原代基质培养物后，建立了产生LP-1的基质细胞系。从贴壁基质细胞系的培养上清液中，将该因子纯化至单一的25kD蛋白。这种物质作用于未成熟淋巴细胞，能与细胞上的特异性受体结合，且与先前描述的造血因子不同。LP-1已被纯化约10^7倍，总回收率为35%。纯化后的蛋白比活性约为4×10^6 U/μg蛋白，在10^(-13) M的半最大浓度下具有活性。
