Effects of the very late adhesion molecule 4 antagonist WAY103 on human peripheral blood eosinophil vascular cell adhesion molecule 1-dependent functions.

Background: Eosinophil infiltration to the lung in allergic inflammation can be initiated by the tethering of circulating cells through very late adhesion molecule 4 (VLA-4; alpha4beta1, CD49d/CD29) to vascular cell adhesion molecule 1 (VCAM-1) expressed on pulmonary vascular endothelium. Small-molecule VLA-4 antagonists have been proposed as a therapeutic mechanism to prevent eosinophil infiltration in asthma; however, they might affect other eosinophil functions.

Objective: The small-molecule VLA-4 antagonist (2S)-3-(4-Dimethylcarbamoyloxyphenyl)-2-{[(4R)-5,5-dimethyl-3-(1-methyl-1H-pyrazole-4 sulfonyl)thiazolidine-4-carbonyl]amino}propionic acid (WAY103) was assessed for its effects on eosinophil VLA-4-dependent functions, including adhesion, migration, respiratory burst, and degranulation.

Peripheral blood eosinophils from patients with allergic asthma contain increased intracellular eosinophil-derived neurotoxin.

Background: One mechanism of the eosinophil's contribution to airway inflammation in asthma is through release of cationic granule proteins to cause airway injury. Differences in either the intracellular concentration of granule proteins or the extent of activated degranulation between eosinophils from healthy patients and those with allergy and asthma could, therefore, relate to fundamental differences in this cell's function.

Objective: To identify phenotypic differences in eosinophil-derived neurotoxin (EDN) content and release in eosinophils from healthy patients, those with allergy, and those with allergy and asthma.