Open AccessThe TTTT B lymphocyte stimulator promoter haplotype is associated with good response to rituximab therapy in seropositive rheumatoid arthritis resistant to tumor necrosis factor blockers
Author(s) -
Fabris Martina,
Quartuccio Luca,
Vital Ed,
Pontarini Elena,
Salvin Sara,
Fabro Cinzia,
Zabotti Alen,
Benucci Maurizio,
Manfredi Mariangela,
Ravagnani Viviana,
Biasi Domenico,
Atzeni Fabiola,
SarziPuttini Piercarlo,
Morassi Pia,
Fischetti Fabio,
Bazzicchi Laura,
Saracco Marta,
Pellerito Raffaele,
Cimmino Marco,
Carraro Valeria,
Semeraro Angelo,
Schiavon Franco,
Caporali Roberto,
Bortolotti Roberto,
Govoni Marcello,
Fogolari Federico,
Tonutti Elio,
Bombardieri Stefano,
Emery Paul,
De Vita Salvatore
Publication year - 2013
Publication title -
arthritis & rheumatism
Language(s) - English
Resource type - Journals
eISSN - 1529-0131
pISSN - 0004-3591
DOI - 10.1002/art.37707
Subject(s) - rheumatoid arthritis , b cell activating factor , medicine , rituximab , immunology , rheumatoid factor , erythrocyte sedimentation rate , haplotype , odds ratio , gastroenterology , tumor necrosis factor alpha , b cell , antibody , biology , gene , genotype , biochemistry
Objective To investigate the polymorphisms in the promoter region of the B lymphocyte stimulator (BLyS) gene as markers of response to rituximab (RTX) in rheumatoid arthritis (RA). Methods The study was first conducted in 152 Italian RA patients and then replicated in an additional 117 RA patients (73 Italian, 44 British). The European League Against Rheumatism response criteria were used to evaluate the response rate at months 4 and 6 after the first cycle of RTX, by means of the Disease Activity Score in 28 joints using the erythrocyte sedimentation rate; patients were classified according to the best response shown between months 4 and 6. BLyS promoter polymorphisms were analyzed by polymerase chain reaction followed by the analysis of the restriction fragments, BLyS promoter haplotypes were analyzed using the expectation‐maximization algorithm, and BLyS serum levels were analyzed using enzyme‐linked immunosorbent assay. Odds ratios (ORs) were calculated with 95% confidence intervals (95% CIs). Results The TTTT BLyS promoter haplotype appeared to be significantly associated with response to RTX only in the subset of seropositive patients (those positive for rheumatoid factor and/or anti–cyclic citrullinated peptide). The replication study confirmed that this association was limited to seropositive RA patients in whom treatment with anti–tumor necrosis factor (anti‐TNF) agents had previously failed. In the whole series of seropositive patients in whom anti‐TNF agents had previously failed, patients carrying the TTTT BLyS promoter haplotype were more prevalent in good responders (18 of 43 [41.9%]) than in moderate responders (20 of 83 [24.1%]) or in nonresponders (1 of 21 [4.8%]) (for good responders versus nonresponders, OR 14.4 [95% CI 1.77–117.39], P = 0.0028). Furthermore, multivariate analysis selected the TTTT BLyS promoter haplotype as an independent marker of good response to RTX (for good responders versus nonresponders, OR 16.2 [95% CI 1.7–152.5], P = 0.01; for good responders versus moderate responders and nonresponders combined, OR 3.1 [95% CI 1.2–7.8], P = 0.02). The relationship between BLyS polymorphisms and BLyS serum levels remained unclear. Conclusion BLyS promoter genotyping may be suitable for identifying seropositive RA patients who may have a good response to RTX after anti‐TNF agents have failed.