Contribution of neutrophils to the clearance of bacteria in a murine model of tolerance to LPS”

LANDONI V.I; CHIARELLA P; MARTIRE GRECO D; SCHIERLOH P; LABORDE E; BASILE J; REARTE B; ISTURIZ M.A; FERNANDEZ G.C

Buenos Aires Argentina

Congreso; French-Argentine Immunology Congress; 2010

The exposure to repetitive doses of LPS generates a refractory state known as tolerance to LPS. Despite impaired immune functions during tolerance, the clearance of infections is increased. Our aim was to address the contribution of neutrophils (PMN) in the enhanced clearance in a murine model of tolerance to LPS. Daily i.v. inoculation of LPS (5mg, Tol) or saline (Sn) was administered for 4 days. To determine the ability of PMN to eliminate an infection, we depleted peritoneal macrophages by chlodronate-loaded liposomes treatment prior to an i.p. polymicrobial bacterial challenge (5x106 colony formation units, CFU). The remaining CFU in the peritoneum 4h after challenge were lower in Tol (Sn=13125±1773;Tol=6822±1988;p