Brouet J C, Mariette X, Chevalier A, Hauttecoeur B
Laboratory of Immunology and Immunopathology, U.108 INSERM, Hôpital Saint-Louis, Paris, France.
J Neuroimmunol. 1992 Feb;36(2-3):209-15. doi: 10.1016/0165-5728(92)90052-m.
We determined the association constant of eight monoclonal IgM with two of their targets, i.e. the myelin-associated glycoprotein (MAG) or the sulfated glucuronic paragloboside (SGPG). All IgM had a 10- to 100-fold higher affinity for MAG than for SGPG. The affinity of the different IgM for MAG ranged from 1.3 x 10(-6) to 7 x 10(-9) mol/liter. The Scatchard plots for MAG were curvilinear, half of the sites being of high or low affinity. In contrast, the plots were linear in the assay using SGPG. No obvious correlations were found between the fine specificity of these IgM for the glucuronyl sulfate epitope and their affinity, although most IgM with a high affinity reacted exclusively with SGPG derivatives retaining a sulfate group. There was no parallelism between the severity of the neuropathy and the affinity of the IgM for MAG or SGPG.
我们测定了8种单克隆IgM与其两个靶标,即髓鞘相关糖蛋白(MAG)或硫酸化葡糖醛酸副球蛋白(SGPG)的结合常数。所有IgM对MAG的亲和力比对SGPG的亲和力高10至100倍。不同IgM对MAG的亲和力范围为1.3×10⁻⁶至7×10⁻⁹mol/升。MAG的Scatchard图呈曲线,一半位点具有高亲和力或低亲和力。相比之下,在使用SGPG的测定中,图呈线性。尽管大多数具有高亲和力的IgM仅与保留硫酸基团的SGPG衍生物反应,但这些IgM对硫酸葡糖醛酸表位的精细特异性与其亲和力之间未发现明显相关性。神经病变的严重程度与IgM对MAG或SGPG的亲和力之间没有平行关系。