Magnani J L, Steplewski Z, Koprowski H, Ginsburg V
Cancer Res. 1983 Nov;43(11):5489-92.
Monoclonal antibody 19-9, produced by a hybridoma prepared from spleen cells of a mouse immunized with a human colon carcinoma cell line, detects an antigen in the serum from most patients with gastrointestinal and pancreatic cancer (M. Herlyn, H.F. Sears, Z. Steplewski, and H. Koprowski, J. Clin. Immunol., 2: 135-140, 1982). The epitope of this antibody is a carbohydrate with the sugar sequence (formula; see text) in which NeuNAc is N-acetylneuraminic acid, Gal is galactose, GlcNAc is N-acetylglucosamine, and Fuc is fucose. In the colon carcinoma cell line and many gastrointestinal and pancreatic cancers, this sequence occurs in a monosialoganglioside containing a sialylated Lea-active pentasaccharide (sialylated lacto-N-fucopentaose II, IV3-alpha-NeuNAc-III4-alpha-Fuc-LcOse4, in which LcOse4 is Gal beta 1-3GlcNAc beta 1-3Gal beta 1-4Glc) (J. L. Magnani et al. J. Biol. Chem., 257: 14365-14369, 1982). However, the antigen in the sera of patients occurs mainly as a mucin, not a ganglioside, based on the following evidence. Little antigen is extracted by organic solvents from sera, and that which is extracted remains at the origin under conditions of thin-layer chromatography where the ganglioside antigen migrates up the plate. Upon gel filtration of serum on Sephacryl S-400, the antigen is eluted in the void volume, indicating a molecular weight of greater than or equal to 5 X 10(6). Incubation for 5 hr at 37 degrees in 0.1 N NaOH destroys the serum antigen but does not affect the ganglioside antigen. The density of the serum antigen as determined in a CsCl gradient is 1.50 g/ml, while in 4 M guanidine. HCl its density is 1.43 g/ml. Finally, antigen affinity purified by antibody 19-9 from the serum of a cancer patient belonging to the Le(a-b+) blood group contains Leb antigen, consistent with the multiple antigenic specificities exhibited by mucins.
单克隆抗体19-9由用人类结肠癌细胞系免疫的小鼠脾细胞制备的杂交瘤产生，可在大多数胃肠道和胰腺癌患者的血清中检测到一种抗原（M. Herlyn、H.F. Sears、Z. Steplewski和H. Koprowski，《临床免疫学杂志》，2: 135 - 140，1982年）。该抗体的表位是一种具有糖序列（分子式；见正文）的碳水化合物，其中NeuNAc是N-乙酰神经氨酸，Gal是半乳糖，GlcNAc是N-乙酰葡糖胺，Fuc是岩藻糖。在结肠癌细胞系以及许多胃肠道和胰腺癌中，该序列存在于一种含有唾液酸化Lea活性五糖的单唾液酸神经节苷脂中（唾液酸化乳糖-N-岩藻五糖II，IV3-α-NeuNAc-III4-α-Fuc-LcOse4，其中LcOse4是Galβ1-3GlcNAcβ1-3Galβ1-4Glc）（J. L. Magnani等人，《生物化学杂志》，257: 14365 - 14369，1982年）。然而，基于以下证据，患者血清中的抗原主要以粘蛋白形式存在，而非神经节苷脂。有机溶剂从血清中提取的抗原很少，且提取出的抗原在薄层层析条件下停留在原点，而神经节苷脂抗原会在薄板上向上迁移。血清在Sephacryl S - 400上进行凝胶过滤时，抗原在空体积中洗脱，表明分子量大于或等于5×10(6)。在0.1N NaOH中于37℃孵育5小时会破坏血清抗原，但不影响神经节苷脂抗原。在CsCl梯度中测定的血清抗原密度为1.50 g/ml，而在4M胍盐酸盐中其密度为1.43 g/ml。最后，用抗体19-9从一名Le(a - b+)血型的癌症患者血清中亲和纯化得到的抗原含有Leb抗原，这与粘蛋白所表现出的多种抗原特异性一致。
