Adoptive transfer of CD68-GFP and CX₃CR1^GFP monocytes. (A-B) Monocytes were isolated from CD68-GFP bone marrow using negative immunomagnetic selection (see “Methods”). Isolated monocytes were characterized as 7/4^high/Ly6G^low, with a typical yield of 70% monocytes, of which 70% to 80% were positive for GFP. (C) A total of 1.5 × 10⁶ isolated CD68-GFP monocytes were adoptively transferred into C57BL/6J mice by IV injection 30 minutes after intraperitoneal injection with 100 μg zymosan. Mice were euthanized at 16 hours, and peritoneal lavage and blood samples were taken. Adoptively transferred GFP⁺ monocytes were present in peritoneal lavage (range 2 to 3 × 10⁴) and blood of animals that received zymosan. (D) Recruited cell numbers are expressed as mean ± SEM of 6 mice. (E-F) Representative flow cytometry plots of peritoneal lavage from C57BL/6J mice that received adoptively transferred GFP positive monocytes from CD68-GFP or CX₃CR1^GFP mice (IV) during ongoing zymosan-induced peritonitis. (E) Mice were euthanized at 16 hours, and recruited monocytes were analyzed. (F) Mice were euthanized at 72 hours, and GFP⁺ monocytes that had differentiated into macrophages were identified using F4/80 and CD11b.