title: Gene profiling in white blood cells predicts infliximab responsiveness in rheumatoid arthritis.
abstract: As indicators of responsiveness to a tumour necrosis factor (TNF)alpha blocking agent (infliximab) are lacking in rheumatoid arthritis, we have used gene profiling in peripheral blood mononuclear cells to predict a good versus poor response to infliximab. Thirty three patients with very active disease (Disease Activity Score 28 >5.1) that resisted weekly methotrexate therapy were given infliximab at baseline, weeks 2 and 6, and every 8th week thereafter. The patients were categorized as responders if a change of Disease Activity Score 28 = 1.2 was obtained at 3 months. Mononuclear cell RNAs were collected at baseline and at three months from responders and non-responders. The baseline RNAs were hybridised to a microarray of 10,000 non-redundant human cDNAs. In 6 responders and 7 non-responders, 41 mRNAs identified by microarray analysis were expressed as a function of the response to treatment and an unsupervised hierarchical clustering perfectly separated these responders from non-responders. The informativeness of 20 of these 41 transcripts, as measured by qRT-PCR, was re-assessed in 20 other patients. The combined levels of these 20 transcripts properly classified 16 out of 20 patients in a leave-one-out procedure, with a sensitivity of 90% and a specificity of 70%, whereas a set of only 8 transcripts properly classified 18/20 patients. Trends for changes in various transcript levels at three months tightly correlated with treatment responsiveness and a down-regulation of specific transcript levels was observed in non-responders only. Our gene profiling obtained by a non-invasive procedure should now be used to predict the likely responders to an infliximab/methotrexate combination.
authors.affiliation: CHU de Rouen, Hôpitaux de Rouen, Service de Rhumatologie, Rouen, F-76000, France.
authors.forename: Thierry
authors.initials: T
authors.lastname: Lequerré
authors.forename: Anne-Christine
authors.initials: AC
authors.lastname: Gauthier-Jauneau
authors.forename: Carine
authors.initials: C
authors.lastname: Bansard
authors.forename: Céline
authors.initials: C
authors.lastname: Derambure
authors.forename: Martine
authors.initials: M
authors.lastname: Hiron
authors.forename: Olivier
authors.initials: O
authors.lastname: Vittecoq
authors.forename: Maryvonne
authors.initials: M
authors.lastname: Daveau
authors.forename: Othmane
authors.initials: O
authors.lastname: Mejjad
authors.forename: Alain
authors.initials: A
authors.lastname: Daragon
authors.forename: François
authors.initials: F
authors.lastname: Tron
authors.forename: Xavier
authors.initials: X
authors.lastname: Le Loët
authors.forename: Jean-Philippe
authors.initials: JP
authors.lastname: Salier
mesh_terms: D000328:Adult; D000368:Aged; D000911:Antibodies, Monoclonal / Q000627:therapeutic use*; D018501:Antirheumatic Agents / Q000627:therapeutic use*; D001172:Arthritis, Rheumatoid / Q000097:blood* / Q000188:drug therapy*; D005260:Female; D005500:Follow-Up Studies; D020869:Gene Expression Profiling; D006801:Humans; D000069285:Infliximab; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000378:metabolism*; D020411:Oligonucleotide Array Sequence Analysis; D011237:Predictive Value of Tests; D012333:RNA, Messenger / Q000097:blood; D013997:Time Factors; D016896:Treatment Outcome; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors
chemical_list: D000911:Antibodies, Monoclonal; D018501:Antirheumatic Agents; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; D000069285:Infliximab