Uesson M, Hansson U B
Scand J Immunol. 1982 Sep;16(3):249-56. doi: 10.1111/j.1365-3083.1982.tb00720.x.
IgG-IgG and IgG-IgM complexes were isolated from one rheumatoid arthritis (RA) serum by affinity chromatography to immobilized F(ag')2 gamma of specific antibodies against unique determinants in the complexes. Both IgG nd IgM, when isolated from these complexes, contained the unique determinants. The circular dichroism (CD) spectrum of IgG differed from that of normal IgG at neutral pH. At pH 3 both IgG and IgM displayed normal CD spectra, and only one third of the molecules now had affinity for the immobilized ligand. The molecules with affinity at pH 3 exhibited an abnormal CD spectrum at pH 3, and a normal CD spectrum was obtained only of those components that lacked affinity. One-third of the Fab gamma isolated from the IgG and IgG complexes with the unique determinants contained the unique determinants that were lacking in the rest of the same principal the Fc gamma fragments. The CD of the two Fab gamma preparations showed the same principal differences as the CD of the molecules with and without affinity to the ligand at acidic pH.
通过亲和层析从一份类风湿性关节炎（RA）血清中分离出IgG-IgG和IgG-IgM复合物，该亲和层析是针对复合物中独特决定簇的特异性抗体的固定化F(ag')2γ进行的。从这些复合物中分离出的IgG和IgM均含有独特的决定簇。在中性pH条件下，IgG的圆二色性（CD）光谱与正常IgG的不同。在pH 3时，IgG和IgM均显示出正常的CD光谱，此时只有三分之一的分子对固定化配体具有亲和力。在pH 3时具有亲和力的分子在pH 3时呈现异常的CD光谱，只有那些缺乏亲和力的组分才获得正常的CD光谱。从具有独特决定簇的IgG和IgG复合物中分离出的三分之一的Fabγ含有独特的决定簇，而同一主要Fcγ片段的其余部分则缺乏该决定簇。两种Fabγ制剂的CD显示出与酸性pH下对配体有亲和力和无亲和力的分子的CD相同的主要差异。
