Platelets in Systemic Sclerosis: the Missing Link Connecting Vasculopathy, Autoimmunity, and Fibrosis?
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Purpose of Review
Platelets are no longer recognized solely as cell fragments regulating hemostasis. They have pleiotropic functions and they are linked directly or indirectly with the three cornerstones of systemic sclerosis (SSc): vasculopathy, autoimmunity, and fibrosis. In this review, we summarize the current knowledge on the potential role of platelets in the pathogenesis of SSc.
Experimental evidence suggests that vasculopathy, a universal and early finding in SSc, may activate platelets which subsequently release several profibrotic mediators such as serotonin and transforming growth factor β (TGFβ). Platelets may also cross-react with the endothelium leading to the release of molecules, such as thymic stromal lymphopoietin (TSLP), that may trigger fibrosis or sustain vascular damage. Finally, activated platelets express CD40L and provide costimulatory help to B cells, something that may facilitate the breach in immune tolerance.
Preclinical studies point to the direction that platelets are actively involved in SSc pathogenesis. Targeting platelets may be an attractive therapeutic approach in SSc.
KeywordsSystemic sclerosis Scleroderma Platelets Serotonin TGFβ PDGF VEGF Microparticles
Compliance with Ethical Standards
Conflict of Interest
The authors declare that they have no conflict of interest.
Human and Animal Rights and Informed Consent
This article does not contain any studies with human or animal subjects performed by any of the authors.
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