Gating strategy for identifying BrdU+ monocytes.

<p>In order to identify BrdU+ monocytes after <i>in vivo</i> BrdU injection, we used flow cytometry on whole blood. We first gated on the monocytes based on their forward (FSC) vs. side scatter (SSC) properties (far left panel), then excluded HLA-DR negative cells as well as T-lymphocytes using anti-CD3, NK cells using anti-CD8 and B-lymphocytes using anti-CD20 (second panel from left). Next, we examined monocytes based on their expression of CD14 and CD16 (right top panel). We examined the expression of Ki-67 and BrdU on monocytes (including CD14+CD16−, CD14+CD16+ and CD14−CD16+) (bottom right panel). For the purpose of this study, CD14−CD16− cells were excluded from all further analyses since this population contains CD34+ hematopoietic stem cells and dendritic cells (bottom left panel). This gating and data are representative of an infected rapid progressor at day 27 post-infection out of all animals studied.