Macrophage migration inhibitory factor in patients with juvenile idiopathic arthritis.
OBJECTIVE
To evaluate serum and synovial fluid (SF) levels of macrophage migration inhibitory factor (MIF) and in vitro MIF production by peripheral blood mononuclear cells (PBMCs) in patients with juvenile idiopathic arthritis (JIA).


METHODS
Serum, SF, and culture supernatant levels of MIF were measured by enzyme-linked immunosorbent assay. Production of MIF by PBMCs was investigated by culturing PBMCs in the absence or presence of 2 different concentrations of concanavalin A.


RESULTS
Serum MIF levels were increased in patients with JIA, and the highest levels were present in patients with systemic-onset JIA. In systemic-onset JIA, serum levels of MIF correlated with the persistence of systemic features and the number of active joints. PBMCs from patients with systemic-onset JIA, when cultured under unstimulated conditions or at suboptimal stimulation, released higher amounts of MIF compared with those from patients with oligoarticular-onset JIA or healthy controls. MIF levels in the SF of patients with systemic-onset JIA were significantly higher than those in patients with oligoarticular-onset JIA. In individual joints, in both systemic-onset JIA and oligoarticular-onset JIA, SF MIF levels were inversely correlated with the duration of the clinical remission induced by intraarticular administration of triamcinolone hexacetonide.


CONCLUSIONS
MIF appears to be a relevant cytokine in the pathogenesis of JIA, particularly in systemic-onset JIA.
Meazza
Cristina
C
University of Pavia, IRCCS Policlinico San Matteo, Italy.
Travaglino
Paola
P
Pignatti
Patrizia
P
Magni-Manzoni
Silvia
S
Ravelli
Angelo
A
Martini
Alberto
A
De Benedetti
Fabrizio
F
D000293:Adolescent; D000893:Anti-Inflammatory Agents / Q000008:administration & dosage; D001171:Arthritis, Juvenile / Q000188:drug therapy / Q000209:etiology / Q000276:immunology*; D002478:Cells, Cultured; D002648:Child; D002675:Child, Preschool; D006801:Humans; D007270:Injections, Intra-Articular; D008263:Macrophage Migration-Inhibitory Factors / Q000032:analysis / Q000096:biosynthesis* / Q000097:blood; D008264:Macrophages / Q000166:cytology* / Q000378:metabolism*; D013582:Synovial Fluid / Q000737:chemistry / Q000166:cytology; D014222:Triamcinolone Acetonide / Q000008:administration & dosage / Q000031:analogs & derivatives*
D000893:Anti-Inflammatory Agents; D008263:Macrophage Migration-Inhibitory Factors; D014222:Triamcinolone Acetonide; C005900:triamcinolone hexacetonide