Antibodies against a protein called collagen II may be associated with a good prognosis in patients with rheumatoid arthritis (RA), according to the results of a recent study.
The study, “Anticollagen Type II Antibodies Are Associated With An Acute Onset Rheumatoid Arthritis Phenotype And Prognosticate Lower Degree Of Inflammation During 5 Years Follow-Up,” was published in the journal Annals of the Rheumatic Diseases.
RA is an auto-immune disorder characterized by chronic joint inflammation, caused by cells from the immune system. In some patients (3 to 27 percent), these cells develop antibodies that target collagen II, a protein that plays an important role in joint cartilage. These antibodies are involved in early inflammation, but their levels decrease in the first year after diagnosis.
“Analyzing these antibodies, in combination with other relevant antibodies, could be used for predicting prognosis and choosing therapy for rheumatoid arthritis patients,” Johan Rönnelid, the study’s senior author from Uppsala University in Sweden, said in a news release.
To investigate whether there is an association between anti-collagen II antibodies and disease development, researchers analyzed the medical data of 773 RA patients from the Swedish Epidemiological Investigation in Rheumatoid Arthritis (EIRA) study, with clinical follow-up data from the Swedish Rheumatology Quality Register (SRQ) registry over five years.
Data included anti-collagen II levels, tender joint count (TJC), swollen joint count (SJC), disease activity score, pain-Visual Analogue Scale (VAS), global-VAS and Health Assessment Questionnaire Score (HAQ).
“We found that patients with collagen antibodies showed increased signs of inflammation during the first six months after diagnosis, after this there was no difference compared to patients without any collagen antibodies,” said Vivek Anand Manivel, the study’s first author. “We also discovered that the presence of collagen antibodies at the time of diagnosis was associated with a better prognosis.”
“Anti-CII [collagen II]-positive patients with RA have an acute onset, but favorable prognosis as compared with the high disease activity at diagnosis. This opens the possibility that early detection of anti-CII together with concomitant clinical signs of elevated disease activity, might associate with a transient inflammatory phenotype, as anti-CII levels diminish during the first year,” the researchers wrote in their study.
Antibodies against proteins known as citrullinated peptides are usually analyzed in RA patients. In this study, the presence of these antibodies correlated with increased inflammation years after diagnosis and a more severe disease progression.
“In all, our findings suggest that a combined analysis of antibodies against collagen and antibodies against citrullinated peptides could be a new tool for predicting the disease course and perhaps also for choosing therapy in newly diagnosed RA patients,” Rönnelid concluded.