Neutrophil activation via β₂ integrins (CD11/CD18): Molecular mechanisms and clinical implications

 

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Summary

Polymorphonuclear neutrophils (PMN) are key components of the innate immunity and their efficient recruitment to the sites of lesion is a prerequisite for acute inflammation. Signaling via adhesion molecules of the β₂ integrin family (CD11/CD18) plays an essential role for PMN recruitment and activation during inflammation. In this review, we will focus on the non-receptor tyrosine kinase Syk, an important downstream signaling component of β₂ integrins that is required for the control of different PMN functions including adhesion,migration and phagocytosis. The exploration of β₂ integrin-mediated Syk activation provided not only novel insights into the control of PMN functions but also led to the identification of Syk as a new molecular target for therapeutic intervention during inflammatory diseases.

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