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Isolation of Murine Peritoneal Macrophages to Carry Out Gene Expression Analysis Upon Toll-like Receptors Stimulation
Published on: April 29, 2015
TNF-alpha, H2O2 and NO response of peritoneal macrophages to Yersinia enterocolitica O:3 derivatives
Iracilda Zeppone Carlos1, Luis Gustavo Silva Monnazzi, Deise Pasetto Falcão
1Departamento de Análises Clínicas, Faculdade de Ciências Farmacêuticas de Araraquara, UNESP, Rua Expedicionários do Brasil, No. 1621, Araraquara, SP, CEP 14.801-902, Brazil. carlosiz@fcfar.unesp.br
Abstract:
In this study, the effect of Yersinia derivatives on nitric oxide (NO), hydrogen peroxide (H2O2) and tumor necrosis factor-alpha (TNF-alpha) production by murine peritoneal macrophages was investigated. Addition of lipopolysaccharide (LPS) to the macrophage culture resulted in NO production that was dose dependent. On the other hand, bacterial cellular extract (CE) and Yersinia outer proteins (Yops) had no effect on NO production. The possible inhibitory effect of Yops on macrophage cultures stimulated with LPS was investigated. Yops partially inhibited NO production (67.4%) when compared with aminoguanidine. The effects of Yersinia derivatives on H2O2 production by macrophages were similar to those on NO production. LPS was the only derivative that stimulated H2O2 release in a dose-dependent manner. All Yersinia derivatives provoked the production of TNF-alpha, but LPS had the strongest effect, as observed for NO production. CE and Yops stimulated TNF-alpha production to a lesser extent than LPS. The results indicate the possibility that in vivo Yops may aid the evasion of the bacteria from the host defense mechanism by impairing the secretion of NO by macrophages.
Insights
Yersinia outer proteins (Yops) partially inhibit nitric oxide (NO) production by macrophages, potentially aiding bacterial evasion. Yersinia derivatives also affect hydrogen peroxide (H2O2) and tumor necrosis factor-alpha (TNF-alpha) release.
Area of Science:
- Immunology
- Microbiology
- Cell Biology
Background:
- Macrophages are key immune cells involved in host defense.
- Yersinia species are pathogenic bacteria that can evade host immune responses.
- Nitric oxide (NO), hydrogen peroxide (H2O2), and tumor necrosis factor-alpha (TNF-alpha) are critical mediators of macrophage-mediated immunity.
Purpose of the Study:
- To investigate the impact of Yersinia derivatives on macrophage production of NO, H2O2, and TNF-alpha.
- To determine if Yersinia outer proteins (Yops) inhibit LPS-stimulated macrophage responses.
Main Methods:
- Murine peritoneal macrophages were cultured and treated with Yersinia derivatives (cellular extract [CE] and Yops) and lipopolysaccharide (LPS).
- Production of NO, H2O2, and TNF-alpha was measured.
- Inhibitory effects of Yops on LPS-stimulated macrophages were assessed.
Main Results:
- LPS stimulated dose-dependent production of NO and H2O2.
- CE and Yops did not stimulate NO or H2O2 production.
- Yops partially inhibited LPS-induced NO production (67.4%).
- All Yersinia derivatives, particularly LPS, induced TNF-alpha production.
Conclusions:
- Yersinia derivatives differentially affect macrophage effector molecule production.
- Yops may impair macrophage NO secretion, potentially contributing to Yersinia immune evasion in vivo.
- Understanding these interactions is crucial for developing strategies against Yersinia infections.
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