To study whether bifunctional NPs indeed target B cells that specifically recognize the β60-74Cit peptide, PBMCs from selected RA patients having high β60-74Cit peptide-specific serum antibody level and from healthy donors were stimulated with the TLR7/TLR8 agonist, R848, and IL-2 for 72 hours, and then the harvested cells were incubated with the bifunctional NPs, followed by the addition of pooled human sera or inactivated sera at different concentrations. This evidence concerns the gene TLR8 and rheumatoid arthritis.