title: Isolation of human and rat natural killer cells.
abstract: We describe a method for the purification of human and rat large granular lymphocytes (LGL), which are known to be the mediators of natural killer (NK) activity in these species. Plastic non-adherent and nylon wool passed blood mononuclear cells were separated into 7 fractions by discontinuous density gradient centrifugation on Percoll. Low density cells were highly enriched in LGL (up to 85% purity), whereas high density cells were typical small and medium sized lymphocytes devoid of NK activity. Human LGL could further be enriched by depleting high affinity sheep erythrocyte rosette-forming cells from the LGL-enriched Percoll fractions (resulting in up to greater than 90% purity). One critical variable in the separation technique was osmolarity, since the separation did not work optimally, if 290 mOsmoles/kg H2O in the Percoll solution was exceeded.
mesh_terms: D000818:Animals; D002448:Cell Adhesion; D002460:Cell Line; D002469:Cell Separation / Q000379:methods*; D002499:Centrifugation, Density Gradient; D006801:Humans; D008214:Lymphocytes / Q000145:classification / Q000276:immunology*; D009994:Osmolar Concentration; D051381:Rats; D011920:Rats, Inbred WF; D012397:Rosette Formation; D013601:T-Lymphocytes / Q000276:immunology