Platelet-activating histone/antihistone IgG complexes in anti-PF4-negative thrombosis and thrombocytopenia syndrome.

ABSTRACT:

Abstract

Thrombosis and thrombocytopenia syndromes (TTS) describe immune-mediated thrombotic adverse reactions after vaccination against COVID-19. Vaccine-induced immune thrombotic thrombocytopenia (VITT) is a well-known subentity of TTS, caused by adenovirus vector-based vaccines. VITT is mediated by anti-platelet factor 4 (PF4) immunoglobulin G (IgG) antibodies, activating platelets via Fc-γ IIa receptors (FcγRIIa). We describe clinical and serological features of 18 patients with anti-PF4/heparin enzyme-linked immunosorbent assay (ELISA)-negative TTS in temporal relationship to messenger RNA (mRNA)-based COVID-19 vaccination. Symptoms began at a median of 7 (range 1 - 61) days after vaccination. Patients showed thrombocytopenia (platelet count 59 × 103/μL; range, 0 to 127 × 103/

SUBMITTER: Esefeld M 

PROVIDER: S-EPMC12402361 | biostudies-literature | 2025 Aug

REPOSITORIES: biostudies-literature