Maintenance of peritoneal macrophages in the steady state.
Resident peritoneal macrophages (M phi) were labeled in situ by intraperitoneal (i.p.) injection of the green fluorescent cell tracking dye PKH-1. After immunofluorescence staining with M phi specific monoclonal antibodies (Mabs) and phycoerythrin (PE) second antibody, the resident M phi were labeled with both the green dye and red Mab label, while recruited M phi were labeled only with the red Mab tag. These populations were distinguished by two-color flow cytometry. PKH-1 labeled resident peritoneal M phi were followed for 1-49 days in mice that received no further treatment (steady state). Dye labeled M phi were still detectable after 49 days in vivo, although their green fluorescence intensity had decreased steadily over time. The decrease in dye intensity was limited to M phi, as the fluorescence intensity of PKH-1 labeled peritoneal lymphocytes did not change. Resident M phi populations were clearly separated from recruited M phi by the intensity of their staining with PKH-1 for up to 28 days. No decrease in the number of resident (dye labeled) peritoneal M phi was observed over 1-28 days. These data indicate that resident peritoneal M phi were not replaced by recruited blood monocytes in the steady state.
Melnicoff
M J
MJ
Department of Immunology, Smith Kline and French Laboratories, King of Prussia, Pennsylvania.
Horan
P K
PK
Breslin
E W
EW
Morahan
P S
PS
D000818:Animals; D000911:Antibodies, Monoclonal; D002452:Cell Count; D002455:Cell Division; D005260:Female; D005455:Fluorescent Antibody Technique; D008264:Macrophages / Q000166:cytology*; D051379:Mice; D008807:Mice, Inbred BALB C; D009504:Neutrophils / Q000166:cytology; D010529:Peritoneal Cavity / Q000166:cytology; D013194:Staining and Labeling
D000911:Antibodies, Monoclonal