This article is more than 5 years old. Information may no longer be current.
Psoriatic arthritis patients showed greater levels of progranulin antibodies
Click Here to Manage Email Alerts
Patients with psoriatic arthritis, particularly those with dactylitis or enthesitis, displayed significant levels of neutralizing progranulin antibodies that were not present in psoriasis patients lacking arthritis symptoms in a recent study.
Researchers in Germany studied 260 patients with psoriatic arthritis (PsA) at three rheumatology centers from October 2011 to July 2012 for the presence of progranulin antibodies (PGRN-Ab). Using ELISA analysis, researchers compared their results with those of patients with psoriasis but without arthritis (n=100; PsC) and healthy controls (n=97).
Fifty PsA patients (19.23%) were PGRN-Ab positive, while one control (1.03%) and none of the PsC patients displayed PGRN-Ab in their sera (P=.0001). Among the PGRN-Ab in the PsA patients, all were tested and belonged to immunoglobulin G class.
In subgroup analysis based on clinical manifestations, PsA patients with dactylitis or enthesitis had significantly greater frequencies of PGRN-Ab (P=.026 and P=.001, respectively). These also occurred more frequently among PsA patients being treated with tumor necrosis factor-alpha (TNF-a) blockers than those treated without TNF-a blockers (20.8% vs. 17.4%; P=.016).
Researchers said PGRN plasma levels were significantly lower among PGRN-Ab patients with PsA than in controls and PsC patients (P<.001) which indicated a neutralizing effect from PGRN-Ab. In addition, when assays were used to compare matched PsA patients with and without PGRN-Ab a proinflammatory effect of progranulin-antibodies was evident.
“In TNF-a induced cytotoxicity assays using WEHI-S and HT-1080 cells, the protective effects of PGRN were inhibited by PGRN-Ab containing sera of patients with PsA,” the researchers concluded. “This suggests that PGRN-Ab might not only be useful as a diagnostic and prognostic marker, but may be involved in the pathogenesis of the arthritic process in a subgroup of patients with PsA.”
Disclosure: See the study for a full list of relevant financial disclosures.
Click Here to Manage Email Alerts