In situ evidence of pulmonary endothelial activation in patients with granulomatosis with polyangiitis and systemic sclerosis.

INTRODUCTION

The aim of this study was to investigate the in situ pulmonary endothelial activation in lung lesions of granulomatosis with polyangiitis (GPA) and systemic sclerosis (SScl).

METHODS

We examined the endothelial expression of ICAM-1, VCAM-1, and E-selectin using immunohistochemistry on formalin-fixed, paraffin-embedded sections of lung lesions of GPA, interstitial lung disease associated with SScl and controls.

RESULTS

A significantly enhanced expression of ICAM-1 and E-selectin was observed in GPA and SScl pulmonary endothelium compared to controls. VCAM-1 was more pronouncedly expressed in GPA compared to SScl.

CONCLUSION

These observations are an evidence of in situ pulmonary vascular endothelial activation in lesions of GPA and SScl, adding information to the pathogenic knowledge of both diseases.