Article

Macrophages and Tissue Injury: Agents of Defense or Destruction?

Department of Pharmacology and Toxicology, Rutgers University, Piscataway, New Jersey 08854, USA.
Annual Review of Pharmacology (Impact Factor: 18.52). 11/2010; 51(1):267-88. DOI: 10.1146/annurev.pharmtox.010909.105812
Source: PubMed

ABSTRACT The past several years have seen the accumulation of evidence demonstrating that tissue injury induced by diverse toxicants is due not only to their direct effects on target tissues but also indirectly to the actions of resident and infiltrating macrophages. These cells release an array of mediators with cytotoxic, pro- and anti-inflammatory, angiogenic, fibrogenic, and mitogenic activity, which function to fight infections, limit tissue injury, and promote wound healing. However, following exposure to toxicants, macrophages can become hyperresponsive, resulting in uncontrolled or dysregulated release of mediators that exacerbate acute tissue injury and/or promote the development of chronic diseases such as fibrosis and cancer. Evidence suggests that the diverse activity of macrophages is mediated by distinct subpopulations that develop in response to signals within their microenvironment. Understanding the precise roles of these different macrophage populations in the pathogenic response to toxicants is key to designing effective treatments for minimizing tissue damage and chronic disease and for facilitating wound repair.

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    • "However, NK cells seem to play a role in pancreas resistance to CVB infection [43] but do not alter the cardiac viral clearance after its depletion [44], or inhibition [45]. Taken together , it seems that in CVB3-induced myocarditis, cardiac infiltrating macrophages have a major role in the early clearance of infected cardiomyocytes in accordance with the assigned dual role of macrophages not only limiting tissue injury but also increasing tissue damage [46]. The fact that macrophage-depleted mice also presented lower body weight suggests that besides their role in chronic myocarditis, macrophages might have additional roles, controlling viral replication and/or tissue damage in other organs. "
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