Selective binding of rheumatoid factors to antigen structures of cytomegalovirus (CMV)

In rheumatoid arthritis patients with malignant progress, short remissions and unimprovement response of activity to therapy Ab with both properties (antiviral and anti IgG) are compared. The selective binding of RF to antigen structures of CMV were tested by 180 patients in a new established ELISA with antiidiotypic goat antibodies of CMV neutralizing human monoclonal Ab and against virus antigen directly. Displacement reactions on the idiotypic binding side as well as comparative ELISA proved the special RF activity. 24.2% of patient suffering from RA with IgM RF showed selective bindings to antigen structures of CMV and anti IgG activity. The evidence of the specific binding capacity of RF to virus antigen in chronical CMV infection as well as their defined binding capacity to the Fc Fragment of IgG suggest CMV specific RF as pathogenetic factor of malignant forms of inflammatory rheumatism.