Figure 2
PBMCs change scatter profile and become contaminated by low-density neutrophils over time. (A) PBMCs were isolated from whole blood using a density gradient (top panel). The forward and side scatter profile of the isolated PBMCs was altered as early as 6 h after collection; this effect was maintained through 24 h and largely reflected a change in size and granularity in lymphocytes (central population moved rightward). By 48 h the scatter profile of the PBMCs had collapsed leftward. In parallel, by 24 h the PBMC fraction showed a large increase in FSChiSSChi granulocytes, consistent with acquisition of a low density phenotype in neutrophils. (B) Neutrophils were enriched from whole blood using immunomagnetic negative selection (bottom panel). This population exhibited a marked dropout of FSChiSSChi cells as early as 6 h. Percents for relevant populations are shown.
