Microarray analysis of the cell cycle-related gene expression from a RAW264 murine macrophage cell line in response to lipopolysaccharide

Understanding the Biology of Self-Renewing Macrophages

Macrophages reside in specific territories in organs, where they contribute to the development, homeostasis, and repair of tissues. Recent work has shown that the size of tissue macrophage populations has an impact on tissue functions and is determined by the balance between replenishment and elimination. Macrophage replenishment is mainly due to self-renewal of macrophages, with a secondary contribution from blood monocytes. Self-renewal is a recently discovered trait of macrophages, which can have a major impact on their physiological functions and hence on the wellbeing of the organism. In this review, I discuss our current understanding of the developmental origin of self-renewing macrophages and the mechanisms used to maintain a physiologically stable macrophage pool.

Dose-dependent effects of Ni (II) ions on production of three inflammatory cytokines (TNF-alpha, IL-1beta and IL-6), superoxide dismutase (SOD) and free radical NO by murine macrophage-like RAW264 cells with or without LPS-stimulation

The effect of Ni (II) ions on macrophages is not well understood. The purpose of this study was to examine the dose-dependent effects of Ni (II) ions up to 1,000 micromol/L on production of three inflammatory cytokines (TNF-alpha, IL-1beta and IL-6), superoxide dismutase (SOD) and nitric oxide (NO) by murine macrophage-like RAW264 cells with (+) or without (-) lipopolysaccharide (LPS) -stimulation. Ni (II) ions caused LPS (-) RAW264 cells to slightly increase production of TNF-alpha and IL-6, proportionally to the Ni (II) ion concentration while IL-1beta was not produced, and to slightly increase production of SOD and NO. It can be concluded that Ni (II) ions dose-dependently increased the inflammatory and oxidative stress conditions of LPS (-) RAW264 cells. LPS-stimulation caused RAW264 cells to produce in abundance the three inflammatory cytokines, SOD and NO. Ni (II) ions dose-dependently reduced the three cytokine quantities and NO amounts in LPS (+) RAW264 cells, while dose-independently increasing SOD amounts. It was noted that Ni (II) ions dose-dependently reduce the resistance power against bacteria of LPS (+) macrophages, because the production of volatile NO--bacteria killer is diminished proportionally to the Ni (II) ion concentration.