basophil

R112 is an ATP-competitive inhibitor of Syk kinase. Ki=6 nM,IC50=226 nM.

Benralizumab (MEDI-563) is a monoclonal antibody targeting the interleukin-5 receptor alpha (IL-5Rα). It enhances antibody-dependent cell-mediated cytotoxicity, leading to a rapid depletion of eosinophils. Benralizumab is used for severe eosinophilic asthma and can be employed to prevent exacerbations of chronic obstructive pulmonary disease.

Tepoxalin (RWJ 20485) is a 5-lipoxygenase inhibitor potentially for the treatment of asthma, osteoarthritis. Tepoxalin inhibits COX-1, COX-2, and 5-LOX. Tepoxalin is a potent inhibitor of sheep seminal vesicle cyclooxygenase (COX) (IC50 = 4.6 microM), rat basophilic leukemia cell (RBL-1) lysate COX (IC50 = 2.85 microM) and COX from intact RBL-1 cells (IC50 = 4.2 microM).

ST-1006, a potent histamine H4 receptor agonist (pKi: 7.94), exhibits significant anti-inflammatory and anti-pruritic effects. It is also a potent inducer of basophil migration.

FR-A 19, a Histamine H2 agonist, inhibits the release of IgE-mediated human basophil histamine in a nanomolar range. It has additional potent anti-allergic properties.

Emedastine (LY188695) is a second generation, selective histamine H1 receptor antagonist with anti-allergic activity. Emedastine reversibly and competitively blocks histamine by binding to H1 receptors, thus blocking its downstream activity. As a result this agent interferes with mediator release from mast cells either by inhibiting calcium ion influx across mast cell/basophil plasma membrane or by inhibiting intracellular calcium ion release within the cells. In addition, emedastine may also inhibit the late-phase allergic reaction mediated through leukotrienes or prostaglandins, or by producing an anti-platelet activating factor effect. Upon ocular administration, emedastine causes a dose-dependent inhibition of histamine-stimulated vascular permeability in the conjunctiva. Emedastine does not affect adrenergic, dopamine, or serotonin receptors.

N tau-methylhistamine is one of the histamine metabolites. N tau-methylhistamine in plasma and urine is a good parameter for histamine release, and the determination of this histamine metabolite is generally less hampered by possible artifacts (due to bas

Tylogenin, a steroidal aglycone generated by acid hydrolysis from two seasonal glycosides occurring in Tylophora sylvatica, inhibits IgE-induced basophil mediator release for allergic reactions. In the rabbit basophil-dependent serotonin release (BDSR) assay system, the inhibitory activity of tylogenin was significantly greater than that of its parent glycosides, tylophoroside and acetyltylophoroside, and that of dexamethasone. The activity of tylogenin was found to increase with the incubation time. In the human leukocyte-dependent histamine release test model, the glycosides had only a minimal activity. In contrast, tylogenin, with a geom mean IC50 = 49 microM, exerted a significantly greater potency than dexamethasone. These results suggest that tylogenin could represent a new class of antiallergic agents.

Thapsigargicin is a sesquiterpene lactone natural product isolated from the poisonous plant Thapsia garganica. Thapsigargicin is a potent non-competitive inhibitor of the sarcoplasmic reticulum/endoplasmic reticulum calcium ATPase (SERCA)(IC₅₀ ≈ 10–30 nM). By specifically blocking the SERCA pump, it depletes endoplasmic reticulum calcium stores and elevates cytoplasmic calcium levels, thereby activating mast cells and leukocytes to release histamine, inducing endoplasmic reticulum stress and apoptosis. Thapsigargicin can be used in studies of calcium signaling pathways and inflammatory responses.