TITLE:
Matrix Metalloproteinase MMP-9 Promotes K/BxN Serum Induced Arthritis in Mice
AUTHORS:
Narendiran Rajasekaran, Harald Illges
KEYWORDS:
MMP-9; Antibody Induced Arthritis; K/BxN; Gelatin Zymography
JOURNAL NAME:
Open Journal of Rheumatology and Autoimmune Diseases,
Vol.4 No.1,
January
23,
2014
ABSTRACT: Matrix metalloproteinases (MMPs) are matrix-degrading enzymes that are over-expressed in joints of rheumatoid arthritis (RA) patients. However, the contribution of specific MMPs for the development of arthritic joints is unknown. This study is aimed at studying the role of matrix metalloproteinase-9 (MMP-9) in mice, using the K/BxN serum-transfer model of RA. Arthritis was induced in Balb/c mice by injecting K/BxN serum. Development of arthritis was followed in these mice by measuring ankle thickness and clinical index score. MMP-9 expression in the joints of mice killed at various time points during the disease progression was determined by gelatin zymography using ankle lysates. We found that MMP-9 expression increased with the severity of arthritis. Importantly MMP-9 deficient mice injected with K/BxN serum showed a milder form of arthritis in comparison to the control C57BL/6 mice injected with K/BxN serum. We therefore conclude that MMP-9 promotes arthritis in mice.