一种新的肝癌中性糖脂抗原HCAl的纯化与分析

PURIFICATION AND CHARACTERIZATION OF A NEW HEPATO-CELLULAR CARCINOMA-ASSOCIATED NEUTRAL GLYCOLIPIDANTIGEN(HCAl)

应用鼠抗人原发性肝细胞癌（ＨＣＣ）单抗Ｈａｂ２０制备免疫亲和层析柱，从ＨＣＣ组织中获得了具有较高特异表达的高纯度肝癌抗原，经高效薄层色谱（ＨＰＴＬＣ）、放射免疫自显影、双向ＨＰＴＬＣ，发现该抗原为一高极性长糖链中性糖脂，其层析行为，免疫组化定位特点及抗原抗体交叉试验，证实它为一种新的肝癌分子标记物，命名为ＨＣＡｌ。通过Ｆｏｌｔｃｈ萃取，高效硅胶层析等方法提取了肝癌及正常肝的中性糖脂，经ＨＰＴＬＣ对比分析，发现肝癌除产生新的特有糖脂条带ＨＣＡｌ外还伴有正常糖脂组份缺失，提示ＨＣＣ可能存在两种反向的糖基转酶活性改变。

A novel hepatocellular carcinoma(HCC)-assiciated neutral glycolipid antigen(HCAl )high-ly expressed in HCC tissues was isolated to homogeneity from HCC tissues using immunoaffinitychromatography on Sepharose-coupled McAbHab20 against HCAl. They were demonstratedthat the purified antigen HCAl was a polar neutral glycolipid with a slower high performancethin layer chromatography(HPTLC)mobility than that of Paraglob and that HCAl could berecognized by Hab20 on autoradiogram of HPTLC immunobinding assay whereas it could notcombine vvith anti-AFP antibody in radioimmunoassay. Comparisons were made betweenHPTLC pattern of neutral glycolipids of HCC and that of normal liver,in which a new specialband with the same HPTLC mobility as HCAl was found in HCC compared to the loss of amain band with a mobility between Golb and Paraglob form HCC,which suggest that there maybe an increase in one glycosyltransferase activity as well as a reduction of another glycosyl-transferase activity in HCC. In this study it is confirmed that HCAl differs from any known tu-mor-associated antigen in immunological pattern and biochemical characterization.