IL33 and sST2 serum level in systemic sclerosis microvascular involvement

Area of Science:

• Immunology and Rheumatology
• Vascular Biology and Medicine

Background:

• Systemic sclerosis (SSc) is characterized by endothelial dysfunction and microvascular damage.
• The role of the Interleukin 33 (IL33) and its receptor ST2 axis in SSc pathogenesis and microvascular complications requires further investigation.

Purpose of the Study:

• To evaluate serum levels of IL33 and soluble ST2 (sST2) in patients with SSc compared to healthy controls (HC).
• To explore the association between IL33/sST2 levels and microvascular manifestations in SSc, including digital ulcers, nailfold capillaroscopy patterns, skin perfusion, and renal vascular involvement.

Main Methods:

• Serum IL33 and sST2 levels were measured in 46 SSc patients and 24 HC.
• Clinical data and microvascular parameters were assessed, including Laser Speckle Contrast Analysis (LASCA) for hand skin perfusion and renal artery ultrasound for resistive index (RRI).
• Nailfold videocapillaroscopy (NVC) was performed, and digital ulcers (DUs) incidence was tracked.

Main Results:

• SSc patients exhibited significantly higher serum IL33 and sST2 levels than HC.
• Elevated IL33 and sST2 levels correlated with the presence of digital ulcers, specific NVC patterns, reduced skin perfusion (LASCA), and increased renal vascular resistance (RRI).
• Higher sST2 levels were associated with a reduced time to developing digital ulcers and predicted new DU development in multivariate analysis.

Conclusions:

• Serum IL33 and sST2 are elevated in patients with systemic sclerosis.
• Soluble ST2 (sST2) may serve as a valuable biomarker for assessing microvascular damage and predicting disease progression, particularly digital ulcer development, in SSc.