EXPRESSION OF ADHESION AND FC-GAMMA-RECEPTORS ON CANINE BLOOD EOSINOPHILS AND NEUTROPHILS STUDIED BY ANTI-HUMAN MONOCLONAL-ANTIBODIES

Commercially available anti-human monoclonal antibodies were tested as markers of adhesion receptors and Fc gamma-receptors on canine neutro phils and eosinophils. Purified populations of eosinophils and neutrop hils were incubated with selected monoclonal antibodies and binding wa s measured by flow cytometry. Most of the anti-human monoclonal antibo dies used in this study crossreacted with canine granulocytes and many showed expression similar to that of human granulocytes. The results suggest that the adhesion and Fc gamma-receptors are well conserved am ong species. Canine eosinophils and neutrophils were simultaneously pu rified by a two-layer Percoll density gradient centrifugation, The pur ity of the neutrophil fraction was greater than or equal to 97% after lysis of the erythrocytes. In the eosinophil fraction, 27-92% were eos inophils (mean 60%). After purification, the neutrophils and eosinophi ls were incubated with selected monoclonal antibodies and analysed by flow cytometry. Human anti-CD11b and CD18 antibodies bound intensely t o both canine eosinophils and neutrophils, Canine neutrophils did labe l with anti-CD29, but eosinophils did not. Anti-CD49d bound weakly to both eosinophils and neutrophils. Both anti-CD16 and anti-CD32 antibod ies labelled neutrophils, but not eosinophils, There was no binding of anti-CD9 to canine neutrophils and the binding of anti-CD9 to canine eosinophils varied between dogs. (C) 1998 Elsevier Science B.V.