Waibel R, O'Hara C J, Smith A, Stahel R A
Department of Medicine, University Hospital of Zurich, Switzerland.
Cancer Res. 1988 Aug 1;48(15):4318-23.
A mouse IgG2a monoclonal antibody, SWA20, defining a tumor-associated cell surface antigen on small cell carcinoma of the lung (SCC) was generated. The reactivity of the antibody with cell lines was examined by indirect immunofluorescence staining and solid phase radioimmunoassay and the reactivity with tissues by immunoperoxidase staining. The antibody reacts with a proportion of small cell carcinoma cell lines (4 of 8) and tissues (7 of 12), but not with other pulmonary or extrapulmonary cell lines (0 of 30) or tumor tissues (0 of 78). The antibody was unreactive with primary cultures of normal bronchial epithelial cells, RBC, and WBC. Immunoperoxidase staining of normal tissues showed rare antigen-positive cells in suprabasal layers of bronchial epithelium and less than 10% of positive cells in colon epithelium. Immunoblots of SCC extracts demonstrated antibody reactivity with a doublet band at Mr 40,000, a broader band at Mr 100,000, and a band at Mr 180,000. The antigen was not present in crude lipid extracts of SCC cells. Solid phase radioimmunoassays and immunoblots showed binding competition with the lectin Triticum vulgaris, sensitivity of the antigen to neuraminidase, and a partial sensitivity to treatment with periodate. The antigen was coexpressed on SCC cell lines with the antigen sGP90-135 defined first by antibody LAM8 (R. Waibel, C. J. O'Hara, and R. A. Stahel. Cancer Res., 47:3766-3770, 1987) but differed from it by lack of reactivity with Lea-positive saliva and partial resistance to periodate treatment. There was no binding competition between radiolabeled antibodies SWA20 and LAM8 to SCC target cells. The IgG2a antibody SWA20 identifies a previously undescribed tumor-associated surface membrane antigen, sGP100, expressed selectively on a proportion of SCC.
制备了一种小鼠IgG2a单克隆抗体SWA20，它可识别肺小细胞癌（SCC）上一种肿瘤相关细胞表面抗原。通过间接免疫荧光染色和固相放射免疫测定检测该抗体与细胞系的反应性，通过免疫过氧化物酶染色检测其与组织的反应性。该抗体与一部分小细胞癌细胞系（8个中的4个）和组织（12个中的7个）发生反应，但不与其他肺或肺外细胞系（30个中的0个）或肿瘤组织（78个中的0个）发生反应。该抗体与正常支气管上皮细胞、红细胞和白细胞的原代培养物无反应。正常组织的免疫过氧化物酶染色显示，支气管上皮基底层以上罕见抗原阳性细胞，结肠上皮中阳性细胞少于10%。SCC提取物的免疫印迹显示，抗体与分子量为40,000的双峰条带、分子量为100,000的较宽条带以及分子量为180,000的条带发生反应。该抗原不存在于SCC细胞的粗脂质提取物中。固相放射免疫测定和免疫印迹显示，该抗原与凝集素普通小麦有结合竞争，对神经氨酸酶敏感，对高碘酸盐处理有部分敏感性。该抗原与抗体LAM8（R. Waibel、C. J. O'Hara和R. A. Stahel. Cancer Res., 47:3766 - 3770, 1987）首先定义的抗原sGP90 - 135在SCC细胞系上共同表达，但与之不同的是，它与Lea阳性唾液无反应，对高碘酸盐处理有部分抗性。放射性标记抗体SWA20和LAM8与SCC靶细胞之间不存在结合竞争。IgG2a抗体SWA20识别一种先前未描述的肿瘤相关表面膜抗原sGP100，它选择性地表达于一部分SCC上。
