Keiser H D
Biochem J. 1982 Jun 1;203(3):691-8. doi: 10.1042/bj2030691.
Tryptic fragments of bovine nasal-cartilage proteoglycan, fractionated by dissociative density-gradient ultracentrifugation, were made to react by immunodiffusion against antiserum to a hyaluronidase-digest subfraction of cartilage proteoglycan monomer. This reaction produced two families of partly superimposed precipitin lines. One family was restricted to gradient fractions of medium or low buoyant density and included the immunoprecipitation reaction attributed to the hyaluronic acid-binding region of the cartilage proteoglycan monomer. The second family of precipitin lines was present alone in gradient fractions of high buoyant density. Immunodiffusion studies with antisera to relatively homogeneous keratan sulphate-rich and chondroitin sulphate-bearing fragment subfractions isolated from the gradient fraction of highest density indicated that both subfractions contained the antigenic determinants responsible for the second family of precipitin lines. Additional immunodiffusion studies, with the use of multispecific antisera to chondroitinase ABC digest and hyaluronidase digest of proteoglycan monomer, confirmed that the two subfractions shared antigenic determinants, and, in addition, indicated that these determinants were on one molecular species in the keratan sulphate-rich fragment subfraction and divided among at least three in the chondroitin sulphate-bearing fragment subfraction. Although an unprecedentedly large number of cartilage proteoglycan antigens could be recognized with the antisera employed in this cartilage proteoglycan antigens could be recognized with the antisera employed in this study, it was not possible to identify antigenic determinants unambiguously specific for the three structurally and functionally distinct regions of the cartilage proteoglycan monomer.
通过解离密度梯度超速离心法分级分离的牛鼻软骨蛋白聚糖的胰蛋白酶片段，与抗软骨蛋白聚糖单体的透明质酸酶消化亚组分的抗血清进行免疫扩散反应。该反应产生了两个部分重叠的沉淀线家族。一个家族局限于中等或低浮力密度的梯度级分，包括归因于软骨蛋白聚糖单体的透明质酸结合区域的免疫沉淀反应。第二个沉淀线家族单独存在于高浮力密度的梯度级分中。对从最高密度梯度级分中分离出的相对均一的富含硫酸角质素和含硫酸软骨素的片段亚组分的抗血清进行免疫扩散研究表明，这两个亚组分都含有负责第二个沉淀线家族的抗原决定簇。使用针对蛋白聚糖单体的软骨素酶ABC消化物和透明质酸酶消化物的多特异性抗血清进行的额外免疫扩散研究证实，这两个亚组分共享抗原决定簇，此外，还表明这些决定簇在富含硫酸角质素的片段亚组分中存在于一种分子物种上，而在含硫酸软骨素的片段亚组分中则至少分布在三种分子物种上。尽管用本研究中使用的抗血清可以识别出数量空前多的软骨蛋白聚糖抗原，但仍无法明确鉴定出对软骨蛋白聚糖单体的三个结构和功能不同区域具有明确特异性的抗原决定簇。
