Postoperative downregulation of MHC class II antigen on monocytes does not differ between open and endovascular repair of aortic aneurysms

Abstract

Objectives: To study immune cell response and histocompability class II (HLA-DR) expression after aortic aneurysm repair. Setting: University hospital, Sweden. Subjects: 42 patients operated on for aortic aneurysm, 26 by an endovascular and 16 by an open technique. Main outcome measures: Analysis of HLA-DR expression and concentrations of blood mononuclear cells by flow cytometry. Splanchnic pH analysed by tonometry and interleukin-6 and tumour necrosis factor-α measured by enzyme-linked immunosorbent assay. Results: The HLA-DR expression on lymphocytes did not change, whereas total HLA-DR expression on monocytes was downregulated, and more pronounced in five patients who developed severe postoperative complications. There were no differences in cell or HLA-DR responses between the two operations. Conclusions: Both endovascular and open repair of aortic aneurysm produced similar downregulation of monocyte HLA-DR expression and similar responses in circulating mononuclear blood cells. There was pronounced downregulation of monocyte HLA-DR expression in patients with severe postoperative complications.