Anti-PF4 antibodies as detected by some PF4/heparin EIAs are not specific for VITT
We provide a functional whole blood flow cytometry test for detection of platelet activating anti-PF4 antibodies in VITT
Vaccination is crucial in combatting the SARS-CoV-2 pandemic. The rare complication of thrombocytopenia and thrombotic complications at unusual sites after ChAdOx1 nCov-19 vaccination is caused by platelet-activating antibodies directed against platelet factor 4. We present a widely applicable whole blood standard flow cytometric assay to identify the pathogenic antibodies associated with vaccine-induced immune thrombotic thrombocytopenia (VITT) after ChAdOx1 nCov-19 vaccination. This assay will enable rapid diagnosis by many laboratories.