Duś D, Ugorski M, Gorczyca W, Radzikowski C
Department of Tumor Immunology, Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wrocław, Poland.
Arch Immunol Ther Exp (Warsz). 1995;43(5-6):273-80.
PNA-reactive sites, representing mainly unmasked Thomsen-Friedenreich (TF) antigen, are predictors of invasive transitional cell carcinoma. The present studies were undertaken in order: 1) to quantify the expression of PNA-reactive sites on well-characterized human urinary bladder cell lines belonging to two different transformation grades (TGr II and TGr III); 2) to identify PNA-binding glycoproteins that are restricted in their expression to tumorigenic and invasive urothelial cell lines. Flow cytometry studies revealed significant differences between TGr II and TGr III cell lines. The mean fluorescence intensities of TGr III, tumorigenic and invasive cells, were in the range of 28.4 to 57.3 arbitrary units. The TGr II cells exhibited several fold lower fluorescence intensity: 9.8 arbitrary units for HCV 29 cell line and 13.1 arbitrary units for Hu 609 cells. Neuraminidase treatment, increasing PNA-binding to TGr II as well as in TGr III cell lines, revealed the presence of cryptic PNA-binding sites. The number of cryptic PNA-binding sites seemed to be similar in TGr II and in TGr III cells and, therefore, only add to the total number of PNA-binding sites on native, untreated cells. Binding of 125I-PNA to all cellular proteins resolved by SDS-PAGE and transferred to nitrocellulose showed multiple bands. The TGr III cells lines, after desialylation, were characterized by the presence of two major PNA-binding components represented by diffuse bands with apparent molecular mass about 68-79 kDa and 116-156 kDa, respectively, and two weakly stained bands with apparent molecular mass of 51 kDa and 60 kDa. Both cell lines representing TGr II expressed high molecular mass PNA-binding component of 207 kDa. They were further characterized by the weaker staining intensity of 116-156 kDa glycoproteins as compared to TGr III cell lines.
PNA反应位点主要代表未被掩盖的汤姆森-弗里德赖希（TF）抗原，是浸润性移行细胞癌的预测指标。开展本研究的目的如下：1）量化属于两种不同转化级别（TGr II和TGr III）的特征明确的人膀胱细胞系上PNA反应位点的表达；2）鉴定其表达仅限于致瘤性和浸润性尿路上皮细胞系的PNA结合糖蛋白。流式细胞术研究揭示了TGr II和TGr III细胞系之间的显著差异。TGr III致瘤性和浸润性细胞的平均荧光强度在28.4至57.3任意单位范围内。TGr II细胞的荧光强度低几倍：HCV 29细胞系为9.8任意单位，Hu 609细胞为13.1任意单位。神经氨酸酶处理增加了PNA与TGr II以及TGr III细胞系的结合，揭示了隐蔽PNA结合位点的存在。隐蔽PNA结合位点的数量在TGr II和TGr III细胞中似乎相似，因此，仅增加了未处理天然细胞上PNA结合位点的总数。125I-PNA与经SDS-PAGE分离并转移至硝酸纤维素膜上的所有细胞蛋白的结合显示出多条带。去唾液酸化后，TGr III细胞系的特征是存在两种主要的PNA结合成分，分别由表观分子量约为68 - 79 kDa和116 - 156 kDa的弥散带代表，以及两条表观分子量为51 kDa和60 kDa的弱染色带。代表TGr II的两种细胞系均表达207 kDa的高分子量PNA结合成分。与TGr III细胞系相比，它们的特征还在于116 - 156 kDa糖蛋白的染色强度较弱。
