Higher expression of annexin A1 in 1 CD56+ than in CD56-T cells : Potential implications for coronary artery disease

• Background: Increased proportions of circulating proinflammatory CD56+ T cells have been reported in patients with coronary artery disease (CAD). Yet, little is known about regulation of these cells. In the present study, we investigated the expression and potential role of the glucocorticoid-mediated protein annexin A1 (AnxA1) in CD56+ and CD56-T cell subsets, with focus on CAD.Methods and Results: We included totally 52 healthy individuals, 28 patients with acute coronary syndrome (ACS) and 57 patients with a history of ACS. AnxA1 mRNA expression was assessed in peripheral blood mononuclear cells. AnxA1 protein expression (total and cell surface-associated) was measured by whole blood flow cytometry in circulating CD56+ and CD56- T cell subsets. Furthermore, inhibitory effects of dexamethasone and/or recombinant AnxA1 on cytokine secretion by CD56+ and CD56- T cells were explored in vitro. We found that CD56+ T cells (the majority CD8+), expressed higher levels of AnxA1 mRNA and protein than did CD56- T cells. When comparing CAD patients with healthy controls, significantly higher levels of cell surface-associated AnxA1 expression were seen in patients, most pronounced in ACS patients. In vitro, dexamethasone reduced cytokine secretion by CD56+ T cells, whereas AnxA1 alone had no effect, and AnxA1 combined with dexamethasone abolished the dexamethasone-induced suppressive effects.Conclusion: AnxA1 was expressed more abundantly in proinflammatory CD56+ T cells. Patients with ACS exhibited increased levels of cell surface-associated AnxA1, thus indicating increased activation of the AnxA1 pathway. Our data further suggested that AnxA1 might counteract glucocorticoid mediated anti-inflammatory effects in T cells.

Ämnesord

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Kardiologi (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Cardiac and Cardiovascular Systems (hsv//eng)

MEDICIN OCH HÄLSOVETENSKAP  -- Medicinska och farmaceutiska grundvetenskaper -- Cell- och molekylärbiologi (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Basic Medicine -- Cell and Molecular Biology (hsv//eng)

Nyckelord

Annexin A1

T cell

CD56

coronary artery disease

acute coronary syndrome

Publikations- och innehållstyp

vet (ämneskategori)

ovr (ämneskategori)