The application of human natural polyclonal IgG-antibodies to Thomsen-Friedenreich epitope (TFE) for evaluation of TFE expression in cancer-associated mucins

Thomsen-Friedenreich epitope (TFE) - specificity of natural polyclonal anti -TF Ige antibodies purified from cancerous sera, human monoclonal anti-TF I gM (TF1), and peanut agglutinin (PNA) in relation to mucin and tumor extrac ts obtained from cancer patients was investigated. The inhibition assay in ELISA with synthetic TF-polyacrylamide showed a different anti-TF IgG antib ody-binding with cancer-associated mucins that appeared to be connected wit h TFE expression and presentation. The mucin and three of ten tumor extract s were bound with anti-TF IgG significantly (up to 100% inhibition at conce ntrations equal to or above 33 mg/ml). The desialylation of faintly reacted tumor extract did not enhance its reactivity with anti-TF IgG antibodies w hile PNA binding strongly increased. The intact extracts (n = 4) did not re act with TF1. Human natural anti-TF IgG antibodies purified by immunoadsorp tion on synthetic TF-PAA-MPG can be used for evaluation of TFE expression i n mucins.