Ooi Y M, Ooi B S
Nature. 1982 Jul 22;298(5872):389-91. doi: 10.1038/298389a0.
The biosynthesis of many of the complement proteins by cells of the monocyte-macrophage series has been established. Studies on these cells using radiolabelled amino acids demonstrated synthesis of precursor proteins (pro-complement), and the native complement protein similar in size to that found in the plasma. However, synthesis of membrane complement proteins has not been demonstrated, although it has been suggested by previous studies using indirect techniques. In particular, there is evidence for the membrane-associated factor B in human lymphocytes. We report here that resident and thioglycollate-stimulated mouse peritoneal macrophages synthesized, in short-term primary cultures membrane factor B of molecular weight (MW) 95,000 and secreted factor B (MW 90,000) as single chain polypeptides. We also found a large single chain polypeptide with an approximate molecular weight of 195,000, which may be the putative factor B precursor.
单核细胞-巨噬细胞系的细胞对许多补体蛋白的生物合成已得到证实。利用放射性标记氨基酸对这些细胞进行的研究表明，它们能合成前体蛋白（补体原），且所合成的天然补体蛋白在大小上与血浆中发现的补体蛋白相似。然而，尽管先前使用间接技术的研究曾提出过膜补体蛋白的合成，但尚未得到证实。特别是，有证据表明人淋巴细胞中存在膜相关因子B。我们在此报告，在短期原代培养中，驻留的和经巯基乙酸盐刺激的小鼠腹腔巨噬细胞合成了分子量（MW）为95,000的膜因子B，并分泌了分子量为90,000的因子B，它们均为单链多肽。我们还发现了一种分子量约为195,000的大单链多肽，它可能是假定的因子B前体。
