Transforming growth factor beta isoforms and TGF-ßR1 and TGF-ßR2 expression in systemic sclerosis patients.

Systemic sclerosis (SSc) is characterized by chronic inflammation and fibrosis, two processes associated with transforming growth factor ß (TGF-ß) functions. In the present study, we investigated the expression of TGF-ß isoforms in serum and the skin distribution of TGF-ß and two receptors (TGF-ßR1 and TGF-ßR2) and their relationship with some clinical, inflammatory, autoimmune (autoantibodies), and vascular (platelets) biomarkers in SSc patients. A total of 56 SSc patients and 120 control subjects (CS) were included. The serum levels of TGF-ß isoforms were quantified by immunoassay with magnetic microspheres, and the skin biopsies were processed by immunohistochemistry. The soluble levels of the three active TGF-ß isoforms were lower in SSc patients than in CS (p < 0.0001). However, sTGF-ß1 and sTGF-ß3 levels were positively correlated with C-reactive protein levels in SSc patients. Additionally, sTGF-ß2 and sTGF-ß3 levels were positively correlated with the number of platelets in SSc patients. In skin biopsies, TGF-ß1, TGF-ßR1, and TGF-ßR2 expression levels were higher in SSc patients than CS. In conclusion, this is the first study showing a joint decrease of the 3 active TGF-ß isoforms in SSc patients. However, TGF-ß1, TGF-ßR1, and TGF-ßR2 are possibly increased in clinically involved skin. Therefore, it is likely that a distinct role is played by TGF-ß at the local (skin lesions) and systemic levels in SSc patients.

Impaired muscle strength is associated with ultrastructure damage in myositis.

The muscle fiber ultrastructure in Idiopathic Inflammatory Myopathies (IIM) has been scarcely explored, especially in Inclusion Body Myositis. The aim of this study was to implement the Scanning Electron Microscopy (SEM) in a small cohort of IIM patients, together with the characterization of immunological profile for a better understanding of the pathophysiology. For immunological profile characterization, we identified the presence of autoantibodies (Ro-52, OJ, EJ, PL7, PL12, SRP, Jo-1, PMScl75, PMScl100, Ku, SAE1, NXP2, MDA5, TIF1γ, Mi-2α, Mi-2ß) and quantified cytokines (IL-1ß, IFN-α2, IFN-γ, TNF-α, IL-6, IL-10, IL-12p70, IL-17A, IL-18, IL-23, IL-33) and chemokines (CCL2, CXCL8). The histological analysis was made by hematoxylin-eosin staining while the muscle fiber ultrastructure was characterized by SEM. We observed changes in the morphology and structure of the muscle fiber according to muscle strength and muscle enzymes. We were able to find and describe muscle fiber ultrastructure with marked irregularities, porosities, disruption in the linearity and integrity of the fascicle, more evident in patients with increased serum levels of muscle enzymes and diminished muscle strength. Despite the scarce reports about the use of SEM as a tool in all clinical phenotypes of IIM, our work provides an excellent opportunity to discuss and reframe the clinical usefulness of SEM in the diagnostic approach of IIM.