Analysis of circulating osteoclast and osteogenic precursors in patients with Gorham-Stout disease.

Purpose: Gorham-Stout disease is a very rare disorder characterized by progressive bone erosion and angiomatous proliferation; its etiopathogenesis is still unknown, and diagnosis is still performed by exclusion criteria. The alteration of bone remodeling activity has been reported in patients; in this study, we characterized circulating osteoclast and osteogenic precursors that could be important to better understand the osteolysis observed in patients.
Methods: Flow cytometry analysis of PBMC (Peripheral Blood Mononuclear Cells) was performed to characterize circulating osteoclast and osteogenic precursors in GSD patients (n = 9) compared to healthy donors (n = 55). Moreover, ELISA assays were assessed to evaluate serum levels of bone markers including RANK-L (Receptor activator of NF-κB ligand), OPG (Osteoprotegerin), BALP (Bone Alkaline Phosphatase) and OCN (Osteocalcin).
Results: We found an increase of CD16 ^- /CD14 ⁺ CD11b ⁺ and CD115 ⁺ /CD14 ⁺ CD11b ⁺ osteoclast precursors in GSD patients, with high levels of serum RANK-L that could reflect the increase of bone resorption activity observed in patients. Moreover, no significant alterations were found regarding osteogenic precursors and serum levels of BALP and OCN.
Conclusion: The analysis of circulating bone cell precursors, as well as of RANK-L, could be relevant as an additional diagnostic tool for these patients and could be exploited for therapeutic purposes.
(© 2024. The Author(s), under exclusive licence to Italian Society of Endocrinology (SIE).)