Mast cells are a source of transforming growth factor β in systemic sclerosis

• Published in: Arthritis and rheumatism Vol. 63; no. 3; pp. 795 - 799
• Main Authors: Hügle, Thomas, Hogan, Vanessa, White, Kathryn E., van Laar, Jacob M.
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 01.03.2011; Wiley
• Subjects: Aged; Biological and medical sciences; Biopsy; Cell Degranulation - physiology; Cytoplasmic Vesicles - metabolism; Cytoplasmic Vesicles - pathology; Dermis - metabolism; Dermis - pathology; Diseases of the osteoarticular system; Female; Humans; Male; Mast Cells - diagnostic imaging; Mast Cells - metabolism; Medical sciences; Microscopy, Immunoelectron; Middle Aged; Sarcoidosis. Granulomatous diseases of unproved etiology. Connective tissue diseases. Elastic tissue diseases. Vasculitis; Scleroderma, Diffuse - metabolism; Scleroderma, Diffuse - pathology; Scleroderma, Limited - metabolism; Scleroderma, Limited - pathology; Transforming Growth Factor beta1 - metabolism; Transforming Growth Factor beta2 - metabolism; Ultrasonography; Immunopathology; Connective tissue disease; Skin disease; Transforming growth factor β; Systemic disease; Rheumatology; Autoimmune disease; Mast cell; Scleroderma
• ISSN: 0004-3591; 1529-0131; 1529-0131
• DOI: 10.1002/art.30190

Objective To describe the cellular source of transforming growth factor β (TGFβ) in the dermis of patients with systemic sclerosis (SSc). Methods We performed electron microscopy (EM) with immunogold labeling on skin biopsy specimens from 7 patients with SSc and 3 healthy control subjects. For TGFβ quantification, the numbers of gold particles per square micron were calculated. The origin of mast cells was confirmed and quantified by toluidine blue staining and light microscopy. Degranulation was assessed on toluidine blue–stained sections and on EM images. Results In all patients, active TGFβ was observed uniquely in mast cell vesicles, some of which were released into the extracellular space. Patients with progressive SSc and a more recent onset of non–Raynaud's phenomenon symptoms had higher numbers of mast cells and gold particles per mast cell. Mast cells from healthy control subjects also contained active TGFβ but, in contrast to SSc samples, showed a resting character with no or low‐level degranulation and uniformly dense osmiophilic vesicles. Conclusion Degranulation of skin mast cells can be an important mechanism of TGFβ secretion in SSc.