In addition, we examined whether this adhesion receptor modulation was still evident on neutrophils when the plasma was removed prior to application of dextran, followed by density gradient centrifugation on Percoll.
To further support our concept that neutrophil activation occurs when whole blood is subjected to the erythrocyte sedimentation prior to density gradient centrifugation, we subjected blood to Ficoll sedimentation followed by centrifugation on Dextran-Hypaque medium.
Dextran sedimentation remains one of the most frequently utilised techniques in neutrophil purification from human blood, typically used in a 2-step procedure with density gradient centrifugation. However, there is a lack of standardisation in its usage as various reports describe applying dextran sedimentation either prior to or following the centrifugation step (as described in several references cited in this discussion).
In this study, we showed that neutrophils purified in the 2-step method with dextran sedimentation preceding Ficoll-Hypaque density gradient centrifugation fit this expression profile of activation, when compared with those purified with dextran sedimentation following centrifugation or the 1-step high-density Ficoll-Hypaque gradient centrifugation method.
In summary, we have presented evidence that subjecting whole blood to dextran sedimentation prior to FicollHypaque density gradient centrifugation leads to neutrophil preparations that are stimulated.
Gerlach, "The function of neutrophils isolated by a magnetic antibody cell separation technique is not altered in comparison to a density gradient centrifugation method," Journal of Immunological Methods, vol.
These problems have, in part, been overcome by the introduction of more rapid procedures, including tube gel electrophoresis [Quantimetrix Lipoprint (7)] and nuclear magnetic resonance (8), and wider recognition of a definitive classification of LDL subclasses based on the comparison methods of density gradient centrifugation
and GGE (4-6).