Purified canine monocytes fail to confer concanavalin-A responsiveness to accessory-cell-depleted lymphocytes.
Monocytes were purified from canine peripheral blood by subjecting Ficoll-Hypaque-separated mononuclear cells to either complement-dependent cytolytic treatment with a panlymphocyte antibody (DLy-6) or rosette formation with human red blood cells (RBCs) followed by adherence to fetal-calf-serum-coated plastic dishes, or sedimentation over discontinuous Percoll gradients. These techniques resulted in monocyte enrichment of 83 +/- 3%, 89 +/-6%, and 42 +/- 3%, respectively. Monocytes purified by either the monoclonal antibody method or rosette formation with human RBCs failed to confer concanavalin-A responsiveness to lymphocytes depleted of accessory cells by discontinuous Percoll gradients. The most potent accessory activity was present among cells from low-density fractions of Percoll gradients and populations that did not form rosettes with human RBCs (monocyte-depleted), indicating that cells other than monocytes are involved in accessory function.
D000818:Animals; D002469:Cell Separation; D002499:Centrifugation, Density Gradient; D003208:Concanavalin A / Q000494:pharmacology*; D004285:Dogs; D004351:Drug Resistance; D006801:Humans; D008213:Lymphocyte Activation / Q000187:drug effects; D008214:Lymphocytes / Q000276:immunology*; D009000:Monocytes / Q000166:cytology / Q000276:immunology*; D012397:Rosette Formation
D003208:Concanavalin A