Predictors of Chronic Obstructive Pulmonary Disease Exacerbations

Takeo Ishii; Kozui Kida


Curr Opin Pulm Med. 2014;20(2):138-145. 

In This Article

New Viewpoints From a SIGLEC-14 Study: Longevity and Unwanted Inflammation

During evolution, Siglec-14, which was necessary to protect humans from bacterial infections in a preindustrialized era in which antibiotics were not yet in existence, may induce unwanted chronic inflammation with a chronic disease such as COPD, as the human life expectancy at birth has increased during the industrialized era,[48] which possibly led to the emergence of a frequent-exacerbation phenotype. Severe, excessive inflammation, that surpasses the amount necessary for the protection against infectious pathogens, is one of the COPD exacerbation characteristics and is treated with a systemic steroid as standard therapy, which is different from that of a pneumonia or acute bronchitis treatment. As lipopolysaccharide (LPS) induced matrix metalloproteinase (MMP)-9 in our COPD-exacerbation mouse model[56] and MMP-12 protein expression in alveolar macrophages induced by LPS was correlated to the severity of emphysema in humans,[57] excessive expression of proteases including MMPs caused by repetitive exacerbations might cause COPD progression.