Cellular immune responses to platelet factor 4 and heparin complexes in patients with heparin‐induced thrombocytopenia

Essentials The immunogenesis of Heparin-induced thrombocytopenia (HIT) is not well understood. Immunization to platelet factor 4 (PF4)-heparin occurs early in life, before any heparin exposure. PF4 and PF4-heparin complexes induce the proliferation of CD14⁺ cells. Reduced levels of regulatory cytokines contribute to immune dysregulation in HIT. SUMMARY: Background Heparin-induced thrombocytopenia (HIT) is an adverse reaction to heparin …