title: The role of regulatory T cells in familial Mediterranean fever (FMF).
abstract: The role of regulatory T cells (T-regs) in familial Mediterranean fever (FMF) was never evaluated. Preliminary studies that we have conducted suggested a rise in the number of regulatory T cells after FMF attacks reaching a maximal level at 7 days. The aim of this study was to evaluate the percentage and activity of regulatory T cells in FMF. Six patients with refractory FMF and six healthy controls were evaluated. The percentage of T-reg cells and forkhead box protein 3 (Foxp3) expression was evaluated and compared between four states: FMF in remission, FMF at the first day of an attack, FMF 7 days after the start of the attack, and healthy controls. Four females and two males were included. All patients had FMF with high severity score, 2.8 ± 0.4 (0-3). The mean age was 31.6 ± 6.2. The mean age at onset was 9.3 ± 9.3. The mean colchicine dose was 2.6 mg ± 0.4. The expression of Foxp3 7 days after the attacks was significantly higher than in FMF at the first day of the attack, FMF in remission, and healthy controls 10.08 ± 2.36 vs. 7.005 ± 0.3 vs. 5.3 ± 1.06 vs. 4.44 ± 1.8; p < 0.05 (Fig.1). The percentage of T-regs in peripheral blood was not statistically different between the four groups. Theexpression of Foxp3 by T-regs increases 7 days after attacks of FMF. Anti-inflammatory cytokines interleukin-10 and TGF-β are known to activate T-regs and have been reported to increase in FMF attacks in line with the present findings. It is suggested that T-regs may have a role in terminating FMF attacks.
authors.affiliation: Rheumatology Unit, Bnai Zion Medical Center, POB 4940, Haifa 31048, Israel. doronrimar@gmail.com
authors.forename: D
authors.initials: D
authors.lastname: Rimar
authors.forename: I
authors.initials: I
authors.lastname: Rosner
authors.forename: G
authors.initials: G
authors.lastname: Slobodin
authors.forename: N
authors.initials: N
authors.lastname: Boulman
authors.forename: E
authors.initials: E
authors.lastname: Toubi
authors.forename: A
authors.initials: A
authors.lastname: Kessel
authors.forename: R
authors.initials: R
authors.lastname: Peri
authors.forename: M
authors.initials: M
authors.lastname: Rozenbaum
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000378:metabolism; D003078:Colchicine / Q000627:therapeutic use; D010505:Familial Mediterranean Fever / Q000188:drug therapy / Q000276:immunology / Q000378:metabolism / Q000473:pathology*; D005260:Female; D051858:Forkhead Transcription Factors / Q000378:metabolism; D006801:Humans; D053645:Interleukin-2 Receptor alpha Subunit / Q000378:metabolism; D018655:Lymphocyte Count; D008297:Male; D012074:Remission Induction; D012720:Severity of Illness Index; D050378:T-Lymphocytes, Regulatory / Q000276:immunology / Q000378:metabolism / Q000473:pathology*
chemical_list: D015415:Biomarkers; C418974:FOXP3 protein, human; D051858:Forkhead Transcription Factors; C508017:IL2RA protein, human; D053645:Interleukin-2 Receptor alpha Subunit; D003078:Colchicine