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A biomarker panel that includes matrix metalloproteinases-degraded type III collagen and other markers may help assess psoriatic arthritis flares.

A serum biomarker panel may represent a new tool for assessing flares in psoriatic arthritis, according to results published in Arthritis Research & Therapy.

To determine the role of protease-mediated biomarkers in indicating inflammation and tissue remodeling, Vinod Chandran, MD, PhD, and colleagues measured a wide panel of protease-mediated biomarkers in serum and synovial fluid (SF).

The biomarkers included, among others, C3M (matrix metalloproteinases [MMP]-degraded type III collagen), C4M (MMP-degraded type IV collagen), PRO-C3 (pro-peptide of type III collagen), PRO-C6 (type VI alpha-3 chain collagen), and CPa9-HNE (HNE-mediated degradation of calprotectin).

Samples were taken from patients with PsA during a flare. Biomarker levels in serum were compared with a control group and with patients with early PsA and not experiencing a flare, defined as PsA without flare. The researchers examined biomarker levels in SF among patients with a PsA flare and compared them with the levels in SF among patients with osteoarthritis (OA).

Multiple Biomarkers Elevated With Flare

The researchers obtained serum samples from 30 patients with PsA flare and analyzed the results together with 99 self-reported healthy donors (controls) and 98 patients with PsA without flare.

In serum, PRO-C3 and C3M levels—which reflect formation and degradation—were significantly higher in PsA-flare versus controls and PsA without flare. type IV 7 S domain collagen was also significantly higher in PsA-flare versus PsA without flare, according to the study results.

Markers related to inflammation and immune cell activity, including C-reactive protein metabolite (CRPM), MMP-degraded vimentin (VICM, and CPa9-HNE, were significantly higher in patients with PsA flare versus controls and those with PsA without flare. Further, VICM (area under the curve [AUC]=0.71), CPa9-HNE (AUC=0.89), CRPM (AUC=0.76), and PRO-C3 (AUC=0.86) demonstrated good discriminatory performance for separating those with PsA flare from PsA without flare.

In SF, the macrophage activity marker VICM was significantly elevated; the type II collagen formation marker type II collagen formation marker was significantly lower in the PsA flare versus OA.

Using Biomarkers for Clinical Assessment

The results show that a serum biomarker panel may represent a novel tool for quantitative assessment of flares in PsA.

“Longitudinal studies need to be conducted to better define the relationship between these biomarkers and PsA disease activity, including flares,” Dr. Chandran and colleagues wrote. “In the future, such a marker or marker panel may be used to evaluate whether there is a need for alternative therapeutic management and/or preventive therapeutic intervention before a flare.”