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

Abstract

An alkali-insoluble fraction 1 (F1), which contains mainly ß-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 < 0.01) leukocyte recruitment into the peritoneal cavity (8.4 x 10 6 cells/ml) when compared with PBS alone (5.5 x 10 6 cells/ ml). Moreover, F1 selectively (P < 0.01) induced eosinophil recruitment (1 x 10 6 cells/ml) when compared to the control group (0.07 x 10 6 cells/ml). Treatment with TRFK-5 significantly (P < 0.01) inhibited eosinophil recruitment (0.18 x 10 6 cells/ml) by F1 without affecting recruitment of mononuclear cells or neutrophils. We conclude that the F1 fraction of the cell wall of H. capsulatum induces peritoneal eosinophilia by an IL-5-dependent mechanism. Depletion of this cytokine does not have effect on the recruitment of other cell types induced by F1.

Modulation of eosinophil generation and migration by Mangifera indica L. extract (Vimang®)

“…Total BALF and peritoneal cavity leukocyte counts were immediately performed in a Neubauer chamber. Differential counts were performed using Rosenfeld-stained cytospin preparations [11].…”

“…Total cell counts were performed using diluting solution in a Neubauer chamber. Differential counts were obtained using Rosenfeld-stained smears [11].…”

“…Cytokines have an important role in the allergic inflammation [7]. Interleukin (IL)-5 is crucial in orchestrating the eosinophilic inflammation and antibodies against IL-5 have been extensively used to inhibit eosinophil accumulation in different experimental models [8][9][10][11]. This cytokine specifically supports terminal differentiation, proliferation of eosinophils precursors and activates mature eosinophils [12][13][14][15].…”

Differential modulation of cell recruitment and acute edema in a model of Polybia paulista venom-induced inflammation

“…Such leukotrienes are inflammatory mediators and have been shown to recruit leukocytes, such as neutrophils and eosinophils, in various animal and human models [13][14][15]32,33]. In a previous study, we demonstrated that MK 886 inhibited recruitment of neutrophils and eosinophils to the peritoneal cavity after administration of the alkali-insoluble fraction 1 from the cell wall of Histoplasma capsulatum, a dimorphic pathogenic fungus [34]. In the present study, treatment with MK 886 resulted in dose-dependent inhibition of neutrophil and eosinophil recruitment, although no effect on mononuclear cell recruitment was observed (Fig.…”

Anti-inflammatory activity of Dasyphyllum brasiliensis (Asteraceae) on acute peritonitis induced by β-glucan from Histoplasma capsulatum

“…Leukocyte recruitment to the site of inflammation is a fundamental event in the inflammatory process. Acute peritonitis promoted by ␤-glucan of cell walls from Histoplasma capsulatum greatly induces leukocyte recruitment, including NE, to the peritoneal cavity (Medeiros et al, 1999;Sá-Nunes et al, 2004). This model is easy to reproduce and is widely used in our laboratory to screen plants extracts, their fractions as well as secondary metabolites regarding their anti-inflammatory activity (Rogerio et al, 2006).…”