Rheumatoid FactorArthritis, RheumatoidImmunoglobulin MImmunoglobulin GAutoantibodiesAntigen-Antibody ComplexPeptides, CyclicCryoglobulinsCryoglobulinemiaAntibodies, AntinuclearLatex Fixation TestsAntibodies, Anti-IdiotypicImmunoglobulin ANephelometry and TurbidimetryImmunoglobulin IdiotypesEnzyme-Linked Immunosorbent AssayRheumatoid NoduleSjogren's SyndromeImmune SeraSynovial FluidCross ReactionsPrecipitinsRheumatic DiseasesAntirheumatic AgentsComplement Fixation TestsAntibody SpecificityArthritisImmunoglobulin Fc FragmentsBlood SedimentationCitrullineHemagglutination Testsgamma-GlobulinsFalse Positive ReactionsComplement C1HLA-DR4 AntigenArthritis, JuvenileEndocarditis, Subacute BacterialArthrographyHLA-DRB1 ChainsAutoimmune DiseasesSynovitisImmunoglobulin AllotypesImmunoglobulinsComplement Activating EnzymesImmunoglobulin Gm AllotypesStaphylococcal Protein AVasculitis, Leukocytoclastic, CutaneousEpitopesLupus Erythematosus, SystemicHLA-DR AntigensBiological MarkersCollagen DiseasesBinding Sites, AntibodyJointsB-LymphocytesAntibodies, MonoclonalImmunoglobulin Heavy ChainsImmunoassayComplement C1qImmunoglobulin Variable RegionJoint DiseasesAutoantigensFelty SyndromeComplement System ProteinsAntibodies, ViralImmunoglobulin IsotypesComplement ActivationFluorescent Antibody TechniqueComplement C3VasculitisRadioimmunoassaySyphilis, CongenitalAgglutination TestsSeverity of Illness IndexSensitivity and SpecificityRubella virusComplement C4Connective Tissue DiseasesAntibodies, BacterialMice, Inbred MRL lprHybridomasAntigen-Antibody ReactionsImmunoglobulin Light ChainsProtein Tyrosine Phosphatase, Non-Receptor Type 22Immunoglobulin kappa-ChainsAntibodiesBlood Protein DisordersImmunoglobulin Fab FragmentsGenes, Immunoglobulin