Inhibits platelet aggregation, vasoconstriction, and angiogenesis through binding to distinct eicosanoids involved in inflammation (acts as a scavenger), and has a role in inhibiting host innate immunity by impairing platelet-assisted formation of neutrophil extracellular traps (NETs) (PubMed:20889972, PubMed:26110417). Inhibits platelet aggregation by collagen (IC(50)=30 nM), thromboxane A2 mimetic (TXA2 mimetic), or arachidonic acid (AA) without affecting aggregation induced by ADP, convulxin (GP6 agonist), PMA, and ristocetin (vWF-dependent platelet agglutinator) (PubMed:20889972, PubMed:26110417). Binds with high affinity to TXA2, TXB2, prostaglandine H2 mimetic (PGH2 mimetic), PGD2, PGJ2, and PGF2alpha (PubMed:20889972). Also interacts with 15(S)-hydroxyeicosatetraenoic acid (HETE), being the first calycin/lipocalin described to date to bind to a derivative of 15-lipoxygenase (PubMed:20889972). Binding is not observed to other prostaglandins, leukotrienes, HETEs, lipids, and biogenic amines (PubMed:20889972). It prevents contraction of rat uterus stimulated by PGF2alpha and induces relaxation of aorta previously contracted with TXA2 mimetic (PubMed:20889972). In addition, it inhibits angiogenesis mediated by 15(S)-HETE and does not enhance inhibition of collagen-induced platelet aggregation by SQ29548 (TXA2 antagonist) and indomethacin (PubMed:20889972). Also impairs platelet-assisted formation of neutrophil extracellular traps (NETs) (PubMed:26110417). NETs are web-like structures of DNA and proteins that play an important role in killing of pathogens (PubMed:26110417). In addition, NETs are implicated in thrombus formation (PubMed:26110417). In vivo, this protein exhibits antithrombotic activity in two distinct mice models that are highly dependent on platelets (PubMed:26110417). It is noteworthy that it inhibits thrombosis without promoting excessive bleeding (PubMed:26110417). Expressed in salivary glands. Very abundant protein in the salivary gland, accounting for at least 30% of total salivary lipocalins. Belongs to the calycin superfamily. Triabin family.