Oka S, Suzuki H, Jyo T, Tsuji M
Int Arch Allergy Appl Immunol. 1979;59(4):408-19. doi: 10.1159/000232288.
Under monitoring the antigenic activity by radioimmunoassay (RIA), one of the major sea-squirt antigens was isolated by gel chromatography after treatment of the extract from internal organs of sea-squirt with QAE-Sephadex. This antigen was fairly homogenous as judged from its elution profile in chromatography on a column of Ultrogel AcA 44 with respect not only of the antigenic activity but also to UV absorption. Furthermore, the antigen inhibited the binding of the 125I-labeled tracer antigen to rabbit anti-sea-squirt antibody in a similar mode to the case of Ei-2, one of the sea-squirt antigens previously prepared, but its specific activity was as high as 2.33 times that of Ei-2. Accordingly this isolated antigen was corresponded to the major antigenic substance in Ei-2 and referred to as Ei-M. In addition, the other antigen of Gi-x was also isolated by chromatography on a column of Sepharose 6B as the major antigenic substance in Gi-2, the other one of the previous antigens. Gi-x was apparently different from E-M in the mode of inhibition of the binding of the tracer antigen to the antibody, although its antigenic activity against the asthmatic patients in vivo was as high as that of Ei-M. Thus, it was considered that sea-squirt contained at least two types of antigens of Ei-M and GI-X.
通过放射免疫测定法（RIA）监测抗原活性时，在用QAE-葡聚糖处理海鞘内脏提取物后，通过凝胶色谱法分离出一种主要的海鞘抗原。从该抗原在Ultrogel AcA 44柱上的色谱洗脱图谱判断，其不仅在抗原活性方面，而且在紫外吸收方面都相当均一。此外，该抗原抑制125I标记的示踪抗原与兔抗海鞘抗体结合的模式，与先前制备的海鞘抗原之一Ei-2的情况相似，但其比活性高达Ei-2的2.33倍。因此，这种分离出的抗原相当于Ei-2中的主要抗原物质，被称为Ei-M。此外，另一种Gi-x抗原也通过在Sepharose 6B柱上的色谱法分离出来，作为先前抗原之一Gi-2中的主要抗原物质。尽管Gi-x对体内哮喘患者的抗原活性与Ei-M一样高，但其在抑制示踪抗原与抗体结合的模式上明显不同于Ei-M。因此，认为海鞘至少含有两种类型的抗原，即Ei-M和GI-X。
