Eosinophils play an important role in the pathogenesis of asthma, and can be activated by extracellular nucleotides, released following cell damage and inflammation. This study aimed at identifying the P2X receptor(s) present on eosinophils and investigating their contribution to eosinophil biology.Human eosinophils were isolated from the blood of normal and asthmatic volunteers. qPCR and Western blot were used to determine respectively P2X receptor mRNA and protein expression level in eosinophils from healthy and asthmatic donors. Conventional whole cell patch-clamp experiments were performed to identify the functional subtypes of P2X receptors in eosinophils. Eosinophil CD11b (active form) cell surface expression was measured by flow cytometry.qPCR showed that P2X1, P2X4 and P2X5 receptor transcripts were expressed in eosinophils from 3 healthy and 3 asthmatic donors. The application of ATP (100 μM) elicited a rapidly activating and rapidly desensitizing inward current (75.0±18.6 pA/pF; donors=3) in healthy human eosinophils which was abolished by 1μM of the selective P2X1 receptor antagonist NF449 (2.7±0.5 pA/pF; donors=6, p=0.0313). The P2X1 agonist α,β-meATP (10μM) also induced a fast transient current in eosinophils (18.4±3.2 pA/pF; donors=3) which was totally inhibited by 1 μM NF449 (2.7±1.8 pA/pF; donors=8, p=0.0078). These P2X1-like currents were markedly reduced (66 %) in eosinophils from asthmatic compared to healthy donors (10 μM α,β-meATP-induced currents of 8.4±1.7 pA/pF [donors=12] and 24.4±3.6pA/pF, donors=18, p<0.0001). P2X1 transcript and protein expression level were similar in asthmatic and normal eosinophils, suggesting that reduced P2X1 currents observed in asthmatic eosinophils could result from increased receptor desensitisation. Therefore, eosinophils from asthmatics were treated either with a substantial (10 IU/ml) or a standard dose (0.32 IU/ml) of apyrase before the recordings took place. High concentrations of apyrase rescued P2X1 activity in asthmatic eosinophils [α,β-meATP (10μM)-induced currents of 17.1±4.5 pA/pF for 10 IU/ml and 11.4±2.6 pA/pF for 0.32 IU/ml of apyrase, n=6 donors for each, p=0.0313]. We also investigated the potential contribution of P2X1 receptor to eosinophil integrin CD11b (the αM chain of the αMβ2 integrin) regulation. In healthy eosinophils, 10 μM α,β-meATP-induced a 45.1±22.2% (donors=12) increase in CD11b (active form) cell surface expression versus 0.6±8.4% for asthmatics (donors=9).In summary, human eosinophils express functional P2X1 receptors and their activity is significantly reduced in asthmatics. P2X1 activation increases cell surface expression of CD11b (activate form) in the healthy eosinophil, suggesting a role for these receptors in eosinophil adhesion/migration.