Interleukin-5 mediates peritoneal eosinophilia induced by the F1 cell wall fraction of Histoplasma capsulatum

摘要

An alkali-insoluble fraction 1 (F1), which contains mainly ?-glucan isolated from the cell wall of Histoplasma capsulatum, induces eosinophil recruitment into the peritoneal cavity of mice. The present study was carried out to determine the participation of interleukin-5 (IL-5) in this process. Inbred C57BL/6 male mice weighing 15-20 g were treated ip with 100 μg of anti-IL-5 monoclonal antibody (TRFK-5, N = 7) or an isotype-matched antibody (N = 7), followed by 300 μg F1 in 1 ml PBS ip 24 h later. Controls (N = 5) received only 1 ml PBS. Two days later, cells from the peritoneal cavity were harvested by injection of 3 ml PBS and total cell counts were determined using diluting fluid in a Neubauer chamber. Differential counts were performed using Rosenfeld-stained cytospin preparations. The F1 injection induced significant (P