Hinoda Y, Kakiuchi H, Nakagawa N, Ohe Y, Sugiyama T, Tsujisaki M, Imai K, Yachi A
Department of Internal Medicine (Section 1), Sapporo Medical College, Japan.
Gastroenterol Jpn. 1992 Jun;27(3):390-5. doi: 10.1007/BF02777759.
The antigen MUSE11 detected by a monoclonal antibody (MAb) is an adenocarcinoma-associated antigen, while CA15-3 is a representative breast cancer-associated antigen detected by MAbs 115D8 and DF3. MAb MUSE11 showed higher binding activity to a synthetic peptide corresponding to the tandem repeat motif of the mucin core protein than that of MAb DF3, although MAb DF3 also had a significant binding activity indicating that MAbs MUSE11 and DF3 could recognize an identical polypeptide core. The reactivity of MAb DF3 to a breast cancer cell line MRK-neu-1 was completely abolished by neuraminidase treatment whereas that of MAb MUSE11 was partly conserved. The simultaneous measurement of the antigens MUSE11 and CA15-3 in sera from 35 cancer patients demonstrated that the incidence of abnormal serum level of CA15-3 was lower than that of antigen MUSE11. These data suggest that at least a part of the structural basis for the difference between the serum levels of antigen MUSE11 and CA15-3 could be carbohydrate side chains including sialic acids.
单克隆抗体（MAb）检测到的抗原MUSE11是一种腺癌相关抗原，而CA15-3是由单克隆抗体115D8和DF3检测到的代表性乳腺癌相关抗原。尽管单克隆抗体DF3也具有显著的结合活性，表明单克隆抗体MUSE11和DF3可以识别相同的多肽核心，但单克隆抗体MUSE11对与粘蛋白核心蛋白串联重复基序相对应的合成肽的结合活性高于单克隆抗体DF3。神经氨酸酶处理完全消除了单克隆抗体DF3对乳腺癌细胞系MRK-neu-1的反应性，而单克隆抗体MUSE11的反应性则部分保留。对35例癌症患者血清中的抗原MUSE11和CA15-3进行同步检测表明，CA15-3血清水平异常的发生率低于抗原MUSE11。这些数据表明，抗原MUSE11和CA15-3血清水平差异的结构基础至少部分可能是包括唾液酸在内的碳水化合物侧链。
