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An Immunohistopathologic Study to Profile the Folate Receptor Beta Macrophage and Vascular Immune Microenvironment in Giant Cell Arteritis
06:35

An Immunohistopathologic Study to Profile the Folate Receptor Beta Macrophage and Vascular Immune Microenvironment in Giant Cell Arteritis

Published on: February 8, 2019

Leukocyte and platelet activation in patients with giant cell arteritis and polymyalgia rheumatica: a clue to

Norma Maugeri1, Mattia Baldini, Patrizia Rovere-Querini

  • 1San Raffaele Scientific Institute, University of Vita-Salute San Raffaele, via Olgettina 58, 20132, Milan, Italy.

Autoimmunity
|October 9, 2009
PubMed

Insights

Giant cell arteritis (GCA) patients show increased activated platelets and leukocytes. These activated cells may contribute to inflammation and blood clot risks in systemic vasculitis.

Area of Science:

  • Rheumatology
  • Hematology
  • Vascular Biology

Background:

  • Ischemia is a significant cause of morbidity in giant cell arteritis (GCA).
  • Understanding the role of circulating cells in GCA pathogenesis is crucial.

Purpose of the Study:

  • To investigate circulating platelet and leukocyte activation in patients with GCA and polymyalgia rheumatica (PMR).
  • To determine if cellular activation markers correlate with disease features or inflammation.

Main Methods:

  • Analysis of circulating platelets and leukocytes in GCA patients, PMR patients, and healthy elderly controls.
  • Quantification of platelet activation markers (e.g., P-selectin) and aggregates.
  • Assessment of leukocyte markers, including tissue factor expression.

Main Results:

  • Patients with GCA exhibited a significantly higher proportion of platelets expressing P-selectin.
  • Increased platelet-leukocyte aggregates and elevated tissue factor on leukocytes were observed in GCA patients.
  • These cellular activation differences correlated with P-selectin expression and were independent of clinical features or systemic inflammation.

Conclusions:

  • Activated circulating leukocytes and platelets may play a role in the chronic vessel inflammation characteristic of GCA.
  • These findings suggest a potential contribution of cellular activation to thromboembolic events in systemic large vessel vasculitis.

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