Pathogenese von IgG4-assoziierten Erkrankungen

Zusammenfassung

IgG4-assoziierte Erkrankungen (IgG4-RD) stellen eine besondere Entität dar, deren Pathologie durch die deutliche Polarisierung einer Entzündungsreaktion und die Ausprägung spezifischer anatomischer Strukturen, den tertiären lymphatischen Geweben (tertiary lymphoid tissue, TLT) und der storiformen Fibrose, geprägt sind. Bei der Induktion von IgG4-RD spielen Rezeptoren des unspezifischen Immunsystems, die Toll-like-receptors (TLR) eine wichtige Rolle. Letztlich entsteht am Ort der Immunreaktion ein Mikromilieu, dass durch die Infiltration mit IgG4-positiven Plasmablasten und T-follikulären-Helfer2-Zellen (Tfh2-Zellen) sowie eine vermehrte Expression bestimmter Zytokine, namentlich Interleukin- (IL-)4, IL-5, IL-10, IL-13, IL-33 und Transforming growth factor-beta bestimmt wird. Dieses Mikromilieu fördert die Bildung von TLT und storiformer Fibrose.

Abstract

IgG4-associated disease (IgG4-RD) is a distinct immuno-inflammatory entity. Its pathology is characterised by the polarisation of the immune reaction towards IgG4-production, together with the appearance of tertiary lymphatic tissues (TLT) and storiform fibrosis. Toll-like receptors (TLR) are receptors of the non-specific immune system, and play an important role in the induction of the disease. Finally, the microenvironment is determined by the infiltration of IgG4-positive plasmablasts and T-follicular helper 2 cells (Tfh2 cells) as well as increased expression of certain cytokines, namely interleukin- (IL-)4, IL-5, IL-10, IL-13, IL-33 and transforming growth factor-beta and this emerges at the site of the immune reaction. This microenvironment propagates the formation of fibrotic tissue and TLT.

Schlüsselwörter

IgG4-assoziierte Erkrankung - Pathogenese - Tfh2-Lymphozyten - Storiforme Fibrose

Keywords

IgG4-related disease - pathogenesis - Tfh2-Lymphocytes - storiform fibrosis

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