Hörl W H, Haag-Weber M, Georgopoulos A, Block L H
Department of Medicine, University of Freiburg, Federal Republic of Germany.
Proc Natl Acad Sci U S A. 1990 Aug;87(16):6353-7. doi: 10.1073/pnas.87.16.6353.
A granulocyte inhibitory protein was isolated and characterized from uremic serum by using ion-exchange column chromatography, high-performance size-exclusion chromatography, and immunochemical procedures. The purification process concentrated the protein 240-fold and to a purity of greater than 95%. An overall recovery of 45% was achieved; the purified protein had a specific activity of 104 units per mg of protein. The polypeptide had a molecular weight of approximately 28,000 and an isoelectric point of 4.0-4.5. Amino acid sequencing of the NH2 terminus revealed a single sequence (Asp-Ile-Val-Met-Thr-Gln-Ser-Pro-Gly-Thr-Leu-Ser-Val-Ser-Pro-Gly-Glu-Arg-Ala- Thr) that proved to be nonhomologous with other serum proteins that appear during an inflammatory state. The polypeptide inhibited the uptake of deoxyglucose, chemotaxis, oxidative metabolism, and intracellular bacterial killing by polymorphonuclear leukocytes. A specific rabbit polyclonal antibody raised against the protein nullified these inhibitory changes. We contend that the protein is responsible for the leukocyte dysfunction that is commonly seen in patients with uremia.
通过离子交换柱色谱法、高效尺寸排阻色谱法和免疫化学方法，从尿毒症血清中分离并鉴定了一种粒细胞抑制蛋白。纯化过程使该蛋白浓缩了240倍，纯度超过95%。总体回收率达到45%；纯化后的蛋白比活性为每毫克蛋白104单位。该多肽的分子量约为28,000，等电点为4.0 - 4.5。对氨基末端进行氨基酸测序显示出单一序列（天冬氨酸-异亮氨酸-缬氨酸-甲硫氨酸-苏氨酸-谷氨酰胺-丝氨酸-脯氨酸-甘氨酸-苏氨酸-亮氨酸-丝氨酸-缬氨酸-丝氨酸-脯氨酸-甘氨酸-谷氨酸-精氨酸-丙氨酸-苏氨酸），结果证明该序列与炎症状态下出现的其他血清蛋白不同源。该多肽抑制多形核白细胞对脱氧葡萄糖的摄取、趋化作用、氧化代谢以及细胞内细菌杀伤作用。针对该蛋白制备的特异性兔多克隆抗体消除了这些抑制性变化。我们认为该蛋白是导致尿毒症患者中常见的白细胞功能障碍的原因。
