Published on the April 5, 2016, Rheumatology Network website
By Whitney L.J. Howell
Spanish researchers have uncovered evidence that may be indicative of solid biomarkers for osteoarthritis (OA). Researchers reported their findings at the OARSI 2016 World Congress held in Amsterdam this month.
To date, no such biomarkers exist, but this group of researchers found six potential biomarkers, with one rising to the top as an early prognostic biomarker in osteoarthritis. Without a reliable biomarker in osteoarthritis, making a diagnosis can be difficult.
“We have defined an interesting panel of six biomarker candidates. Some of them (ITIH1 and C3) can also distinguish between OA patients and patients from other rheumatic diseases. Moreover, we have found S100A6 could be a novel potential early and prognostic biomarker in OA,” researchers wrote in the abstract.
To identify whether reliable protein biomarkers could be found, the research team conducted a large-scale study to pinpoint potential knee osteoarthritis indicators.
In an April 1 presentation titled “Identification of a Serum Protein Biomarker Panel for the Diagnosis of Knee Osteoarthritis,” Luca Lourido from the rheumatology division of Hospital Universitario de A. Coruna in Spain, discussed using broad-scale profiling of protein levels in serum to discover novel osteoarthritis biomarkers.
The team applied antibody suspension bean arrays to profile serum knee osteoarthritis samples with different Kellgren-Lawrence (KL) scores (n=288) and compared them to rheumatoid arthritis (n=288), psoriatic arthritis (PsA) (n=288), and healthy controls (n=96). Protein profiles were obtained using 174 antibodies from the Human Protein Atlas, targeting 78 proteins.
Forty-six proteins were further profiled in a focused-bead array to validate results in an independent cohort of serum samples of osteoarthritis patient (n=196), RA (n=192), PsA (n=192), and healthy controls (n=92). Samples were selected based on previous internal protein profile studies. Protein profiles were adjusted for sex, age, and body mass index.
Compared to healthy controls four proteins had elevated levels in serum: S100 calcium binding protein A6, leptin, Complement 3, and Inter-Alpha-Trypsin Inhibitor Heavy Chain. Healthy controls had two elevated proteins – apolipoprotein A1 and vitamin D-binding protein. S100A6 was also found at high levels in KL scores compared to healthy controls in both sample cohorts.
Through this profiling, researchers identified a panel of six biomarker candidates that allow for distinguishing samples from healthy individuals and those with osteoarthritis or other rheumatic diseases. Alterations of these proteins could provide new serum biomarkers that could expand the knowledge of OA biomarkers and lend a better understanding of osteoarthritis pathology.
To read the article at its original location: http://www.rheumatologynetwork.com/OARSI2016/oa-pathology-linked-new-biomarkers
