Rabbit anti-human CSF IgG. I. Characterization of anti-idiotype antibodies produced against MS CSF and detection of cross-reactive idiotypes in several MS CSF.

Serum from rabbits injected with IgG prepared from the CSF of patients with multiple sclerosis were rendered anti-idiotypic by adsorption on sequential columns of pooled human gamma-globulin, free light chains and free heavy chains. Adsorbed antisera precipitated between 15% and 45% of the autologous ligand and were inhibited by autologous CSF and serum and F(ab')2 fragments prepared from serum IgG. Idiotypic cross-reactivities were detected among the CSF IgG of several MS patients using three of these antisera. Two antisera demonstrated low levels of cross-reactivity with CSF IgG obtained from two of six heterologous MS patients. The third antiserum detected highly cross-reactive idiotypic determinants in the CSF IgG of two family members both having MS.