CD44 MEDIATES HA-INDUCED ADHESION AND MIGRATION OF MONOCYTES / 解剖学报

ABSTRACT

Objective To examine the distribution of HA in monocytes and expression of CD44 and ICAM-1 on the monocytes and effects of HA and HA receptors on adhesion and migration of the monocytes. Methods Canine peripheral blood monocytes were isolated by non-continuous density centrifugation with percoll solution.HA on the cell surface,intracellular HA,CD44 and ICAM-l of the monocytes were labeled with immunofluorescence.Effects of HA on the cell surface,substrate HA and free HA on adhesion and migration of the monocytes were examined by digesting HA on the cell surface with HAase,coating the bottom of the dishes and the membrane of the cell culture inserts with HA and adding HA into the medium.Regulating effects of HA receptors on adhesion and migration of the monocytes were investigated after blockade of the receptors. Results There was HA on the surface and in the cytoplasm of the monocytes.CD44 and ICAM-1 were expressed on the monocytes.The adhered and migrated monocytes decreased after HA on the cell surface was digested with HAase.The numbers of the adhered and migrated monocytes were greater when the cells were incubated on HA-coated dishes and membranes of the cell culture inserts.The adhered and migrated monocytes decreased after HA was added into the medium.When CD44 was blocked with antibody,the adhered and migrated monocytes decreased.There were not significant changes in the numbers of the adhered and migrated monocytes after ICAM-1 was blocked with antibody.Conclusion There is HA on the surface and in the cytoplasm of monocytes.HA on the cell surface is essential for adhesion and migration of the monocytes.HA substrate promotes adhesion and migration of the monocytes,while free HA reduces adhesion and migration of the cells.CD44 mediates HA-induced adhesion and migration of the monocytes.