CD4+CD28-T lymphocytes contribute to early atherosclerotic damage in rheumatoid arthritis patients

Background - Peripheral blood expansion of an unusual CD4+ T-cell subset lacking surface CD28 has been suggested to predispose rheumatoid arthritis ( RA) patients to develop more aggressive disease. However, the potential association between CD4+ CD28(null) T cells and early atherosclerotic changes in RA has never been investigated. Methods and Results - The number of circulating CD4 + CD28(null) cells was evaluated in 87 RA and 33 control subjects who also underwent evaluation of carotid artery intima-media thickness (IMT) and endothelial function via flow-mediated vasodilation (FMV). Patients had higher IMT and lower FMV compared with control subjects. The frequency of CD4 + CD28(null) cells was significantly higher in patients than in control subjects. Twenty patients with persistent expansion of circulating CD4 + CD28(null) cells had more marked increase of carotid artery IMT and stronger decrease of brachial artery FMV. Blockade of tumor necrosis factor-alpha led to a partial reappearance of the CD28 molecule on the CD4 + cell surface. Conclusions - Circulating CD4 + CD28(null) lymphocytes are increased in RA. Patients with persistent CD4 + CD28(null) cell expansion show preclinical atherosclerotic changes, including arterial endothelial dysfunction and carotid artery wall thickening, more significantly than patients without expansion. These findings suggest a contribution of this cell subset in atheroma development in RA. Moreover, the demonstration that tumor necrosis factor-alpha blockade is able to reverse, at least in part, the CD28 deficiency on the CD4+ cell surface may be of interest for possible innovative therapeutic strategies in cardiovascular diseases.