ENDOGENOUS MONOCYTE CHEMOATTRACTANT PROTEIN-1 RECRUITS MONOCYTES IN THE ZYMOSAN PERITONITIS MODEL

The rule of monocyte chemoattractant protein-1 (MCP-I) in the recruitm ent of blood-derived monocytes in a model of zymosan peritoneal inflam mation Tvas investigated, After zymosan injection (1 mg) a rapid influ x of polymorphonuclear leukocytes (PMN)) and monocytes into the perito neal cavity associated with mouse MCP-1 (JE) gene activation and prote in secretion in the exudates occurred. MCP-I production (maximal at 4 h) preceded the accumulation of monocytes (F4/80-positive cells, maxim ally recovered between 16 and 24 h), Treatment of mice with a single i njection of anti-mouse MCP-I antibody inhibited 16-h monocyte accumula tion by similar to 40%, however, a significant decrease in the number of PMN was also measured, Finally, intraperitoneal injection of murine recombinant MCP-1 (1 mu g) produced a selective accumulation of monoc ytes (F4/80-positive cells) into the peritoneal cavity. in conclusion, we show the novel existence of a strict relationship between MCP-I pr oduction and leukocyte accumulation in this model of acute inflammatio n.