Correcting the expression of miRNA-155 represses PP2Ac and enhances the release of IL-2 in PBMCs of juvenile SLE patients.

[familial mediterranean fever]

MicroRNA-155 is involved in immune cell , differentiation , maturation and function . MiR-155 showed variable dysregulated expression in autoimmune diseases such as systemic lupus erythematosus (SLE ) and rheumatoid arthritis (RA ) patients . MiR-155 was previously confirmed to directly target CAMP response element binding protein (CREB ), which was previously identified as a positive regulator of protein phosphatase 2 A (PP 2 A ). PP 2 A is a key negative regulator of interleukin-2 , which is an important immune modulator and was previously shown to be decreased in SLE . In this study we aimed at investigating the regulation of PP 2 A by miR-155 and hence its role in juvenile SLE disease pathogenesis . MiR-155 showed significant downregulation in PBMCs from juvenile SLE and juvenile familial Mediterranean fever (FMF ) and significant upregulation in PBMCs from juvenile idiopathic arthritis (JIA ) patients . In SLE , miR-155 expression was negatively correlated with Systemic Lupus Erythematosus Disease Activity Index (SLEDAI ) score and proteinuria and was positively correlated with white blood cell (WBC ) count . The mRNA of the catalytic subunit of PP 2 A (PP 2 A c ) showed significant upregulation in PBMCs from SLE and FMF but not in JIA patients . Additionally , the relative expression of PP 2 Ac mRNA was positively correlated with SLEDAI score . Forced expression of miR-155 led to decreased relative expression of PP 2 Ac mRNA and increased IL -2 release in cultured-stimulated PBMCs . This study suggests for the first time the possible role of an miR-155 -PP 2 Ac loop in regulating IL -2 release and identifies miR-155 as a potential therapeutic target in juvenile SLE disease through relieving IL -2 from the inhibitory role of PP 2 A .

Diseases
Validation

Diseases presenting "arthritis" symptom

acute rheumatic fever

child syndrome

congenital adrenal hyperplasia

cystinuria

familial hypocalciuric hypercalcemia

familial mediterranean fever

focal myositis

harlequin ichthyosis

homocystinuria without methylmalonic aciduria

inclusion body myositis

lamellar ichthyosis

malignant atrophic papulosis

pyomyositis

sneddon syndrome

trochlear dysplasia

typhoid

wiskott-aldrich syndrome

This symptom has already been validated