ImmunoSensation scientists unravel a long standing enigma in crystal-induced chronic inflammation

December 19, 2018 - December 19, 2018

Canvas effect of a Confocal Microscopy image of the phagocytosis of Charcot-Leyden Crystals by human macrophages (c) Bernardo S Franklin

 

A team formed by researchers from the Institute of Innate Immunity, the Institute of Experimental Immunology of the University of Bonn, and the University of Massachusetts Medical School have unraveled a long standing enigma in crystal-induced chronic inflammation. 

It has been known, since 1850, that eosinophil infiltration into tissues results in the accumulation of large extracellular crystals known as Charcot-Leyden crystals (CLCs). CLCs have now been extensively described in the lungs of asthmatics patients as well as in patients with allergic reactions, helminthic infections and in the nose of chronic rhinosinusitis patients. Research on this topic has been considerably slow, for example, it took another 120 years for the biochemical characterization of these crystals, formed by a protein Galectin-10, which is enriched in eosinophil granules. Since then, another gap in knowledge was that their function or activity remained unknown. Whether these crystals are merely a marker of eosinophil demise, or play any role in the disease progression. 

The new study published this week in the Journal of Immunology shows that Charcot-Leyden crystals induce a strong inflammatory response driven by interleukin-1 after the activation of the pattern recognition receptor NLRP3 and formation of inflammasomes. The study suggests that a product of eosinophil degranulation can sustain immune activity, which could have important implications for the development of chronic diseases such as allergic asthma, a chronic airway inflammatory disease that affects 8-12% of people in Europe.

DOI: doi.org/10.4049/jimmunol.1800107