Whole blood was layered onto Ficoll-Paque PLUS (GE Healthcare, Uppsala, Sweden) for density gradient centrifugation and PBMC collection. Cells were immediately stained for flow cytometry, using antibodies to human CD14 (BD, Franklin Lakes, NJ; clone M5E2), CD16 (BD; clone 3G8), and CCR2-APC (R&D Systems, Minneapolis, MN; clone 48607) or isotype matched control antibodies, as described previously.12 (link) Monocyte subsets were acquired with the BD FACSCantoII flow cytometer, and analysis performed using FlowJo software (v. 10.0.8, TreeStar, Ashland, OR). For this analysis, results for CD14+ and CD14+CD16+ expressing monocytes were reported as the percentage of total monocytes; for CCR2+CD14+ and CCR2+CD14+CD16+, as a percentage of CD14+ and CD14+CD16+ monocytes, respectively.