Antibodies against Platelet Glycoproteins in Clinically Suspected VITT Patients
Romy T. Meier,
Leendert Porcelijn,
Suzanne Hofstede-van Egmond,
Camila Caram-Deelder,
Jonathan M. Coutinho,
Yvonne M. C. Henskens,
Marieke J. H. A. Kruip,
An K. Stroobants,
Jaap J. Zwaginga,
C. Ellen van der Schoot,
Masja de Haas,
Rick Kapur
Affiliations
Romy T. Meier
Department of Experimental Immunohematology, Sanquin Research and Landsteiner Laboratory, Amsterdam UMC, University of Amsterdam, 1066 CX Amsterdam, The Netherlands
Leendert Porcelijn
Sanquin Diagnostic Services, Department of Immunohematology Diagnostics, Sanquin, 1066 CX Amsterdam, The Netherlands
Suzanne Hofstede-van Egmond
Sanquin Diagnostic Services, Department of Immunohematology Diagnostics, Sanquin, 1066 CX Amsterdam, The Netherlands
Camila Caram-Deelder
Department of Clinical Epidemiology, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands
Jonathan M. Coutinho
Department of Neurology, Amsterdam UMC, 1105 AZ Amsterdam, The Netherlands
Yvonne M. C. Henskens
Central Diagnostic Laboratory, Maastricht University Medical Centre+, 6229 HX Maastricht, The Netherlands
Marieke J. H. A. Kruip
Department of Haematology, Erasmus MC, Erasmus University Medical Center, 3015 CN Rotterdam, The Netherlands
An K. Stroobants
Department of Clinical Chemistry, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
Jaap J. Zwaginga
Department of Hematology, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands
C. Ellen van der Schoot
Department of Experimental Immunohematology, Sanquin Research and Landsteiner Laboratory, Amsterdam UMC, University of Amsterdam, 1066 CX Amsterdam, The Netherlands
Masja de Haas
Sanquin Diagnostic Services, Department of Immunohematology Diagnostics, Sanquin, 1066 CX Amsterdam, The Netherlands
Rick Kapur
Department of Experimental Immunohematology, Sanquin Research and Landsteiner Laboratory, Amsterdam UMC, University of Amsterdam, 1066 CX Amsterdam, The Netherlands
Vaccine-induced thrombotic thrombocytopenia (VITT) is a rare but severe complication following COVID-19 vaccination, marked by thrombocytopenia and thrombosis. Analogous to heparin-induced thrombocytopenia (HIT), VITT shares similarities in anti-platelet factor 4 (PF4) IgG-mediated platelet activation via the FcγRIIa. To investigate the involvement of platelet-antibodies in VITT, we analyzed the presence of platelet-antibodies directed against glycoproteins (GP)IIb/IIIa, GPV and GPIb/IX in the serum of 232 clinically suspected VITT patients determined based on (suspicion of) occurrence of thrombocytopenia and/or thrombosis in relation to COVID-19 vaccination. We found that 19% of clinically suspected VITT patients tested positive for anti-platelet GPs: 39%, 32% and 86% patients tested positive for GPIIb/IIIa, GPV and GPIb/IX, respectively. No HIT-like VITT patients (with thrombocytopenia and thrombosis) tested positive for platelet-antibodies. Therefore, it seems unlikely that platelet-antibodies play a role in HIT-like anti-PF4-mediated VITT. Platelet-antibodies were predominantly associated with the occurrence of thrombocytopenia. We found no association between the type of vaccination (adenoviral vector vaccine versus mRNA vaccine) or different vaccines (ChAdOx1 nCoV-19, Ad26.COV2.S, mRNA-1273, BTN162b2) and the development of platelet-antibodies. It is essential to conduct more research on the pathophysiology of VITT, to improve diagnostic approaches and identify preventive and therapeutic strategies.
