Ck. Osterland et al., ANTI-GAMMA-GLOBULIN FACTORS IN HUMAN SERA REVEALED BY ENZYMATIC SPLITTING OF ANTI-RH ANTIBODIES - COMMENTARY, Vox sanguinis, 64(4), 1993, pp. 246-247
Human sera were found that contained antibody activity which caused ag
glutination of red cells or particles sensitized with immunoglobulin G
that had first been degraded by pepsin proteolysis. The agglutinating
activity was specific for a determinant that was not present on the u
ntreated, native immunoglobulin. It was found most frequently in sera
from rheumatoid arthritis patients and its titre showed some correlati
on with disease activity.