Serum pro-matrix metalloproteinase-3 as an indicator of disease activity and severity in rheumatoid arthritis: comparison with traditional markers

Stachys schtschegleevii tea, matrix metalloproteinase, and disease severity in female rheumatoid arthritis patients: a randomized controlled clinical trial

BACKGROUND

Stachys schtschegleevii (SSC) is a herbal medicine used to treat infections. To date, this is the first study aimed to investigate the effects of SSC tea on disease activity score (DAS), serum inflammatory biomarkers and matrix metalloproteinases (MMP-1 and MMP-3) among women with rheumatoid arthritis (RA).

METHODS

This pilot, triple-blind, randomized controlled clinical trial was conducted among forty-four women (age: 30-65 years) diagnosed with moderately active RA. Subjects were randomly assigned (1:1 ratio) into either SSC group (2.4 g/day SSC + 2.4 g/day black tea, n=22) or placebo (2.4 g/day black tea, n=22) for 8 weeks. Serum high-sensitivity C-reactive protein (hs-CRP), interleukin-1 beta (IL-1β), and MMPs were measured using ELISA. According to the American College of Rheumatology guideline considering hs-CRP, DAS28 was assessed.

RESULTS

Both study groups had respondent rates above 94.9%. The SSC intervention caused significant reductions in the number and the percent changes of the tender joints (SSC: -74.39% vs. placebo: -57.15%, mean differences= -0.77; P<0.05) and DAS28 [SSC: -32.44% vs. placebo: -22.32%, mean differences= -0.41, P<0.05). Unlike the intervention within SSC group that showed significant reductions in the mean serum levels of hs-CRP, IL-1β, and MMP-3, SSC caused significant MMP-3 reductions (SSC: -20.59% vs. placebo: 1.29%, P<0.05).

CONCLUSION

The SSC intervention showed an appropriate clinical efficacy for female RA patients, accompanying remarkable reductions in the number of tender and swollen joints, DAS28, and serum levels of MMP-3. This can provide additional insights to the interventional studies controlling RA-related pathological and inflammatory outcomes. Trial registration Prospectively registered at the Iranian Registry of Clinical Trials (IRCT), linked to the WHO Registry Network ( https://en.irct.ir/trial/11602 , IRCT registration number: IRCT2015032011335N5, Registration date:2015-05-12). Key Points • Stachys schtschegleevii improved clinical outcomes and attenuated disease severity in RA patients. • Stachys schtschegleevii ameliorated serum level of MMP-3 in RA patients.

Ab locks for improving the selectivity and safety of antibody drugs

Monoclonal antibodies (mAbs) are a major targeted therapy for malignancies, infectious diseases, autoimmune diseases, transplant rejection and chronic inflammatory diseases due to their antigen specificity and longer half-life than conventional drugs. However, long-term systemic antigen neutralization by mAbs may cause severe adverse events. Improving the selectivity of mAbs to distinguish target antigens at the disease site from normal healthy tissue and reducing severe adverse events caused by the mechanisms-of-action of mAbs is still a pressing need. Development of pro-antibodies (pro-Abs) by installing a protease-cleavable Ab lock is a novel and advanced recombinant Ab-based strategy that efficiently masks the antigen binding ability of mAbs in the normal state and selectively "turns on" the mAb activity when the pro-Ab reaches the proteolytic protease-overexpressed diseased tissue. In this review, we discuss the design and advantages/disadvantages of different Ab lock strategies, focusing particularly on spatial-hindrance-based and affinity peptide-based approaches. We expect that the development of different masking strategies for mAbs will benefit the local reactivity of mAbs at the disease site, increase the therapeutic efficacy and safety of long-term treatment with mAbs in chronic diseases and even permit scientists to develop Ab drugs for formerly undruggable targets and satisfy the unmet medical needs of mAb therapy.

MMP3 is a reliable marker for disease activity, radiological monitoring, disease outcome predictability, and therapeutic response in rheumatoid arthritis

Matrix metalloproteinase-3 or MMP3 also known as stromelysin-1 is an enzyme that is actively involved in joint destruction in rheumatoid arthritis (RA) patients. Screening the last three decades, it appears that serum levels of MMP3 reflect positively RA disease activity, joint and bone injury, and radiological erosion and predict disease outcome and drug responsiveness as summarized in several publications reporting outcomes on more than 8000 patients with RA. MMP-3 monitoring should be embedded in the routine assessment and accompany therapeutic modalities, in personalized medical RA management.

Matrix Metalloproteases as Biomarkers of Disease

Matrix metalloprotease play a vital role in many cellular processes. Dysfunction in activity of these enzymes has been implicated in the pathogenesis of a number of diseases. Factors that affect the balanced interaction between MMPs and their inhibitors, such as genetic mutations of extracellular matrix components or dysregulation of MMP expression, can lead to various diseases. Due to their essential role in ECM remodeling, MMPs have become targets of interest as biomarkers for the diagnosis and prognosis of diseases associated with alterations of the ECM.

Alteration of matrix metalloproteinase-3 O-glycan structure as a biomarker for disease activity of rheumatoid arthritis

Background

Nearly all secreted proteins are glycosylated, and serum glycoproteins that exhibit disease-associated glycosylation changes have potential to be biomarkers. In rheumatoid arthritis (RA), C-reactive protein (CRP), and matrix metalloproteinase-3 (MMP-3) are widely used as serologic biomarkers, but they lack sufficient specificity or precision. We performed comparative glycosylation profiling of MMP-3 using a recently developed antibody-overlay lectin microarray technology that allows semicomprehensive and quantitative analysis of specific protein glycosylation to develop an RA-specific disease activity biomarker.

Methods

Serum was taken from patients with RA (n = 24) whose disease activity was scored using composite measures, and MMP-3 was immunoprecipitated and subjected to lectin microarray analysis. A disease activity index (DAI) based on lectin signal was developed and validated using another cohort (n = 60). Synovial fluid MMP-3 in patients with RA and patients with osteoarthritis (OA) was also analyzed.

Results

Intense signals were observed on a sialic acid-binding lectin (Agrocybe cylindracea galectin [ACG]) and O-glycan-binding lectins (Jacalin, Agaricus bisporus agglutinin [ABA], and Amaranthus caudatus agglutinin [ACA]) by applying subnanogram levels of serum MMP-3. ACG, ABA, and ACA revealed differences in MMP-3 quantity, and Jacalin revealed differences in MMP-3 quality. The resultant index, ACG/Jacalin, correlated well with disease activity. Further validation using another cohort confirmed that this index correlated well with several DAIs and their components, and reflected DAI changes following RA treatment, with correlations greater than those for MMP-3 and CRP. Furthermore, MMP-3, which generated a high ACG/Jacalin score, accumulated in synovial fluid of patients with RA but not in that of patients with OA. Sialidase digestion revealed that the difference in quality was derived from O-glycan α-2,6-sialylation.

Conclusions

This is the first report of a glycoprotein biomarker using glycan change at a local lesion to assess disease activity in autoimmune diseases. Differences in the degree of serum MMP-3 α-2,6-sialylation may be a useful index for estimating disease activity.

How should morning function in rheumatoid arthritis be assessed? Bibliographic study of current assessment

In patients with rheumatoid arthritis (RA), symptoms of joint stiffness and pain may be most severe in the morning, resulting in impaired ability to carry out normal morning functions. Although morning stiffness was included in the criteria for classification and remission of RA, defined by the American College of Rheumatology (ACR) in 1987, the approach to assessment of this circadian symptom has not been standardized, and other circadian aspects of the disease (i.e. pain, functional ability) were not included. A bibliographic study of papers published in English in the period January 2007 to January 2010 and reporting morning stiffness, pain or function was undertaken to investigate methods of assessing circadian aspects of RA. A total of 73 studies were identified using Medline, including 62 clinical trials. Full papers were obtained for 52 reports of clinical studies (84%), most of which (44/52, 85%) assessed duration of morning stiffness. Only two studies (4%) specified that severity of morning stiffness was assessed, only three (6%) assessed pain in the morning, and none assessed morning functional ability. These findings suggest the need for consistent reporting of a measure to reflect the impaired morning function, arising from joint stiffness and pain that is commonly experienced by patients.

Interferon-gamma inhibits interleukin-1beta-induced matrix metalloproteinase production by synovial fibroblasts and protects articular cartilage in early arthritis

Introduction

The first few months after symptom onset represents a pathologically distinct phase in rheumatoid arthritis (RA). We used relevant experimental models to define the pathological role of interferon-γ (IFN-γ) during early inflammatory arthritis.

Methods

We studied IFN-γ's capacity to modulate interleukin-1β (IL-1β) induced degenerative responses using RA fibroblast-like synoviocytes (FLS), a bovine articular cartilage explant (BACE)/RA-FLS co-culture model and an experimental inflammatory arthritis model (murine antigen-induced arthritis (AIA)).

Results

IFN-γ modulated IL-1β driven matrix metalloproteinases (MMP) synthesis resulting in the down-regulation of MMP-1 and MMP-3 production in vitro. IFN-γ did not affect IL-1β induced tissue inhibitor of metalloproteinase-1 (TIMP-1) production by RA FLS but skewed the MMP/TIMP-1 balance sufficiently to attenuate glycosaminoglycan-depletion in our BACE model. IFN-γ reduced IL-1β expression in the arthritic joint and prevented cartilage degeneration on Day 3 of AIA.

Conclusions

Early therapeutic intervention with IFN-γ may be critical to orchestrate tissue-protective responses during inflammatory arthritis.

Screening tests for inflammatory activity: applications in rheumatology

Inflammation is a hallmark of rheumatic diseases. The response to tissue injury comprises a series of changes which result in the shedding of pathogens, limitation of tissue damage and restoration of affected structures. These changes depend on increased or decreased serum concentrations of certain proteins known as inflammatory biomarkers. Laboratory analysis of these markers, together with clinical data and other complementary tests enable the assessment of disease activity and treatment response and can indicate the presence of infection. The screening tests currently available for identifying inflammatory activity include the determination of C-reactive protein level and erythrocyte sedimentation rate as well as protein electrophoresis. Here, we review the characteristics of a number of inflammatory biomarkers and their use in the assessment of inflammatory activity in rheumatic diseases.

The role of resident synovial cells in destructive arthritis

Infiltration by inflammatory cells, thickening of the lining layer, and destructive invasion into cartilage and bone are pathognomic features of the synovium in rheumatoid arthritis (RA). However, the most common cell types at the sites of invasion are resident cells of the joint, in particular synovial fibroblasts. These cells differ from healthy synovial fibroblasts in their morphology, their expression of proto-oncogenes and antiapoptotic molecules, and in their lack of certain tumor suppressor genes. Through their production of proinflammatory cytokines and chemokines mediated by signaling via Toll-like receptors, they are not only effector cells but also active parts of the innate immune system attracting inflammatory immune cells to the synovium. Most importantly, by producing matrix-degrading molecules they contribute strongly to the destructive mechanisms operative in RA.