Are the Current Attempts at Standardization of Antiphospholipid Antibodies Still Useful? Emerging Technologies Signal a Shift in Direction

ABSTRACT

The pathogenic role of antiphospholipid antibodies (aPL) has been widely established over past years in several experimental models and clinical studies. Accordingly, the detection of aPL by immunoassays (anticardiolipin antibodies; anti-β2 glycoprotein I antibodies) has become a routine practice in the clinical workup of patients with systemic autoimmune diseases. aPL are mostly assayed using commercial ELISA kits, whose performance has not been found to be sufficiently concordant among the different manufacturers. In the past years, collaborative groups have spent considerable effort to reach some form of standardization but this process is still ongoing. Such lack of standardization has recently become even more crucial, as manufacturers have had to face an increasing demand for fully automated tests for aPL, like those test systems that have been developed for other autoantibodies (e.g., antinuclear antibodies, anti-ENA antibodies). We therefore report our recent experience with two newly developed automated methods for anticardiolipin antibodies testing. In particular, we discuss the results obtained using routine samples, as we believe that these better reflect the “real-life” situation in which those automated methods will operate. We also mention other emerging technologies in the field of aPL detection.

KEYWORDS

Antiphospholipid antibodies - immunoassays - automation - antiphospholipid syndrome

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