Springer G F, Desai P R
J Biol Chem. 1982 Mar 25;257(6):2744-6.
Immunochemical activity of the Arachis hypogaea lectin has been equated, in spite of its different hapten combining requirements, with that of the human anti-T (Thomsen-Friedenreich) antibody population which is of importance in cancer immunology. We show here by gradual desialation of isolated human blood group MM and NN antigens at pH 2.0, 56 degrees C, that A. hypogaea lectin is, in addition, substantially more tolerant to NeuAc in the vicinity of T antigen's immunodominant repeating structures, Gal beta 1 leads to 3 GalNAc, than human anti-T antibodies. Reactivity with the Arachis lectin appeared first at 20-25% release of NeuAc from the antigens, whereas faint reactivity with anti-T was first recognizable at 50-55% NeuAc release from NN and 65-70% from MM antigen. Remarkably, at these degrees of desialation, the NN and MM antigens had about 50% of maximal activity toward the Arachis lectin. The slower appearance of T antigen upon graded desialation of MM antigen is likely due to the higher concentration of NeuAc and difference in some of its linkages on intact MM as compared to NN antigen.
尽管花生凝集素的半抗原结合要求不同，但它的免疫化学活性已被等同于人类抗 -T（汤姆森 - 弗里德赖希）抗体群体的活性，而后者在癌症免疫学中具有重要意义。我们在此表明，在pH 2.0、56℃条件下对分离出的人类血型MM和NN抗原进行逐步去唾液酸化处理时，与人类抗 -T抗体相比，花生凝集素对T抗原免疫显性重复结构（Galβ1→3GalNAc）附近的NeuAc具有更高的耐受性。与花生凝集素的反应首先出现在抗原中NeuAc释放20 - 25%时，而与抗 -T的微弱反应首先在NN抗原中NeuAc释放50 - 55%、MM抗原中NeuAc释放65 - 70%时才得以识别。值得注意的是，在这些去唾液酸化程度下，NN和MM抗原对花生凝集素的活性约为最大值的50%。MM抗原逐步去唾液酸化时T抗原出现较慢，可能是由于与NN抗原相比，完整MM上NeuAc的浓度更高以及其某些连接方式存在差异。
