{"doi":"10.1136/rmdopen-2024-005111","title":"<i>Porphyromonas gingivalis</i> associates with the presence of anti-citrullinated protein antibodies, but not with the onset of arthritis: studies in an at-risk population","abstract":"Objective The antibody response against Porphyromonas gingivalis ( Pg ) is elevated in rheumatoid arthritis (RA), especially in patients with anti-citrullinated protein antibodies (ACPA). Here, we investigated whether antibodies against the Pg virulence factor arginine gingipain (Rgp) are associated with the RA-risk phase and development of arthritis. Methods At-risk individuals were included in a prospective study (Risk-RA) based on a positive anti-cyclic citrullinated peptide 2 (CCP2) antibody test, and having musculoskeletal complaints but no signs of arthritis. Study participants were followed for ≥3 years (arthritis-free, n=165) or until arthritis onset (progressors, n=95). Anti-Rgp IgG was measured in Risk-RA (260 baseline and 247 follow-up samples) and healthy controls (n=126); anti-CCP2 IgG was measured in Risk-RA (254 baseline samples). Data were analysed in GraphPad Prism and R using log-transformed antibody levels. Results 53% of Risk-RA and 26% of controls, p=0.003, were anti-Rgp IgG positive at baseline, with higher levels in Risk-RA compared with controls, p&lt;0.0001. No changes in anti-Rgp IgG levels were observed during follow-up. The anti-Rgp IgG response at baseline did not associate with the development of arthritis; Cox-regression showed an HR of 0.95 (CI 0.80 to 1.13, p=0.6) for anti-Rgp IgG levels, and 0.82 (CI 0.55 to 1.23, p=0.3) for anti-Rgp IgG positivity. Conclusions Antibodies against the oral bacterium Pg are elevated during the RA-risk phase, both in individuals progressing to arthritis and in individuals remaining arthritis-free. Hence, Pg infection can be linked to the presence of RA-specific autoimmunity, ACPA, and musculoskeletal symptoms, but not to further development of arthritis in this at-risk population.","journal":"RMD Open","year":2025,"id":550106,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":2,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9634,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2025-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":1445436,"name":"Alexandra Cîrciumaru","orcid":null,"position":1,"is_corresponding":false},{"id":1444695,"name":"Linda Mathsson‐Alm","orcid":"0000-0003-1211-7209","position":2,"is_corresponding":false},{"id":459272,"name":"Helga Westerlind","orcid":"0000-0003-3380-5342","position":3,"is_corresponding":false},{"id":1444696,"name":"Marina Dehara","orcid":"0000-0002-0768-7453","position":4,"is_corresponding":false},{"id":1444697,"name":"Yogan Kisten","orcid":"0000-0003-3988-1629","position":5,"is_corresponding":false},{"id":496286,"name":"Barbara Potempa","orcid":"0000-0002-1226-6952","position":6,"is_corresponding":false},{"id":271717,"name":"Jan Potempa","orcid":"0000-0002-3600-7461","position":7,"is_corresponding":false},{"id":28666,"name":"Aase Hensvold","orcid":"0000-0002-7669-3777","position":8,"is_corresponding":false},{"id":909523,"name":"Karin Lundberg","orcid":"0000-0001-7625-964X","position":9,"is_corresponding":false},{"id":909519,"name":"Charlotte de Vries","orcid":"0000-0001-8955-0479","position":0,"is_corresponding":true}],"reference_count":20,"raw_metadata":null,"created_at":"2026-07-19T02:54:12.321988Z","pmid":"39890206","pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}