Unresolved inflammation: ‘immune tsunami’ or erosion of integrity in immune-privileged and immune-responsive tissues and acute and chronic inflammatory diseases or cancer

Abstract

Introduction: Unresolved inflammation is loss of balance between two biologically opposing arms of acute inflammation, ‘Yin’ (tumoricidal) and ‘Yang’ (tumorigenic) processes that cause disruption of protective mechanisms of immune system.

Areas covered: Hypothesis: Unresolved inflammation-induced exaggerated expression of apoptotic and/or wound healing mediators lead to fundamental erosion (‘immune tsunami’ or ‘immune meltdown’) of integrity in tissues that are naturally immune-responsive (immune surveillance); or immune-privileged (immune tolerance). ‘Immune tsunami’ refers to end results of acute or chronic immune dysfunction leading to inflammatory diseases or cancer. Acute inflammatory diseases including drug-induced cancer cachexia, would fit features of ‘immune meltdown’ that are otherwise described for end results of age-associated diseases. Pathogens induce rapid destruction of vascular integrity, gain access to tissues and cause excessive expression of apoptotic factors leading to multiple organ failure (MOF). Significant disruptions of immunological barriers and response shifts lead to chronic neurodegenerative and autoimmune diseases, tumor growth, malignancies and angiogenesis and loss of natural immune response balances.

Expert opinion: Strategies to promote (stabilize) inherent properties of innate immune cells (‘tumoricidal’ versus ‘tumorigenesis’) that would influence polarization of adaptive immune (T or B) cells are key in reducing or preventing incidence of inflammatory and vascular diseases or cancer during aging process.

Keywords::

• acute and chronic inflammation
• angiogenesis
• autoimmune
• cancer
• BBB
• CNS
• cornea
• dendritic cells
• hyperplasia
• immune-privilege
• immune surveillance
• immune tolerance
• innate and adaptive immune cells
• macrophages
• mast cells
• natural killer cells
• neovascularization
• neurodegenerative
• neuroretina
• tissue integrity

Acknowledgements

The comments and opinions presented in this perspective are personal views of the author and not necessarily those of the National Cancer Institute. Earlier studies on experimental models of acute and chronic inflammatory diseases were established in collaboration with John H Rockey, MD, Ph.D. and his team at the University of Pennsylvania, School of Medicine, Department of Ophthalmology, Philadelphia, PA. The author is grateful to Mr. Alan Hoofring at NIH Medical Arts for his expertise in preparing the art work.

Notes

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