Pharmacology General e2d194b0 Heparin induced thrombocytopenia is due to antibodies against A PF - 1 B PF - 2 C PF - 3 D PF - 4 High-Yield Explanation Antibodies against platelet factor-4 (PF-4) causes aggregation of platelets and thrombosis, thus leads to thrombocytopenia.