Rajam P C, Gaudreau C J, Grady A, Rundlett S T
Immunology. 1969 Sep;17(3):367-85.
Fractional ethanol precipitation was used to prepare a concentrate of brain-specific components of thermostable (BE) antigens derived from heated extract of human brain. Chromatography on DEAE-cellulose yielded a well-defined acidic protein peak containing brain-specific material corresponding to a minimum of two brain-specific components. Preparation of a protein fraction (RSP) from unheated human brain ribonucleoprotein is described. Chromatography of RSP on DEAE-cellulose permitted the isolation of an acid protein fraction (AP) containing brain-specific antigens identical with those from heated brain extracts. AP contained a minimum of three distinct antigenic components which emerged as a single peak on rechromatography, and were incompletely separable by immunoelectrophoresis or analytical ultracentrifugation. Pronase digestion liberated material with the general properties of a glycolipid; digestion products lost ability to precipitate with antiserum to the intact material. Neuraminidase treatment resulted in the appearance of at least one previously masked determinant, presumably related to oligosaccharide residues since the new determinant was destroyed by periodate treatment. Periodate did not affect ability of AP to form immunoprecipitin arcs unless AP was previously desialized. A chloroform-soluble fraction liberated during acid hydrolysis of AP has not been identified. The possible chemical nature and intracellular association of AP are discussed.
采用分级乙醇沉淀法制备了源自人脑加热提取物的热稳定（BE）抗原的脑特异性成分浓缩物。在DEAE-纤维素上进行色谱分析得到一个定义明确的酸性蛋白峰，其中含有脑特异性物质，至少对应两种脑特异性成分。描述了从未加热的人脑核糖核蛋白制备蛋白组分（RSP）的方法。RSP在DEAE-纤维素上的色谱分析使得能够分离出一种酸性蛋白组分（AP），其含有与加热脑提取物中相同的脑特异性抗原。AP至少包含三种不同的抗原成分，在重新色谱分析时呈现为单一峰，并且通过免疫电泳或分析超速离心不能完全分离。链霉蛋白酶消化释放出具有糖脂一般特性的物质；消化产物失去了与抗血清沉淀完整物质的能力。神经氨酸酶处理导致至少一个先前被掩盖的决定簇出现，推测与寡糖残基有关，因为新的决定簇被高碘酸盐处理破坏。高碘酸盐不影响AP形成免疫沉淀弧的能力，除非AP先前已去唾液酸化。AP酸水解过程中释放的氯仿可溶部分尚未鉴定。讨论了AP可能的化学性质和细胞内关联。
