Abstract Number: PB1428
Meeting: ISTH 2020 Congress
Background: Heparin-induced thrombocytopenia (HIT) is a prothrombotic drug reaction caused by platelet activating antibodies with specificity for platelet factor 4 (PF4)/ heparin complexes. Immunoassays to detect those antibodies are essential in the workup of patients with suspected HIT.
Aims: Here, we show first performance data of a fully automated latex enhanced immunoassay for detection of PF4/ heparin complex specific antibodies in human plasma samples on a hemostasis analyzer. *
Methods: The assay is based on latex particles coated with monoclonal antibodies that mimic HIT antibodies with specificity for PF4/ heparin complex. PF4/ heparin antibodies contained in the sample compete with the monoclonal antibodies on the latex particles and decrease the turbidimetric signal which is conversely proportional to the antibody concentration in the sample.
The assay consists of three liquid ready to use reagents. Reagent one is a supplementary reagent containing a blocker to prevent HAMA and RF interference.
Reagent two is the latex reagent and the third one contains PF4 complexed with a polyanion to mimic the PF4/ heparin complex for signal generation. A calibrator automatically diluted by the system is measured to generate a calibration curve.
Results: First performance data of the prototype assay were collected regarding precision, HIL interference, HAMA/RF interference and method comparison data vs. heparin-induced platelet activation (HIPA) assay. Repeatability was between 2.31 – 8.62 % CV. No interference up to 500 mg/dL hemoglobin, 30 mg/dL unconjugated and conjugated bilirubin, 1000 mg/dL triglycerides, 500 mg/dL cholesterol and 2000 IU/mL RF was observed. The immunoassay confirmed all 20 HIPA positive.
Conclusions: We conclude that our latex enhanced immunoassay reliably measures PF4/heparin antibodies in human citrated plasma by using only 10 µl sample volume. The assay might be a helpful tool for the workup of patients with suspected HIT.
To cite this abstract in AMA style:
Ehm M, Christ G, Schwarz H, Vitzthum F, Zander N. First Performance Data of a New Latex Enhanced Immunoassay to Detect HIT Antibodies in Plasma Samples * [abstract]. Res Pract Thromb Haemost. 2020; 4 (Suppl 1). https://abstracts.isth.org/abstract/first-performance-data-of-a-new-latex-enhanced-immunoassay-to-detect-hit-antibodies-in-plasma-samples/. Accessed March 21, 2024.« Back to ISTH 2020 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/first-performance-data-of-a-new-latex-enhanced-immunoassay-to-detect-hit-antibodies-in-plasma-samples/