Mononuclear cell adenosine deaminase and CD26/dipeptidylpeptidase-IV activities are sensitive markers of reperfusion during percutaneous transluminal angioplasty

During ischaemia, the extracellular level of adenosine increases, which has cytotoxic effects. In endothelium, cell surface adenosine deaminase (ADA) complexing CD26 is coordinately induced during ischaemia as part of an adaptative response by eliminating adenosine. We examined whether a similar mechanism exists for mononuclear cells. We studied mononuclear cell surface ADA (MCADA) and dipeptidyl-peptidase IV activity (DPPIV) of membrane CD26 during percutaneous transluminal coronary angioplasty (PTCA) as a model of ischaemia-reperfusion. Enzymatic activities were compared with levels of ischaemia-modified albumin (IMA), a marker of ischaemia-reperfusion.

Methods and results: Patients (15 men and 5 women) with non-ST segment elevation acute coronary syndrome related to a stenosis of proximal left anterior descending artery were prospectively included before revascularization. MCADA, DPPIV and IMA were measured before PTCA (T0) then 15 (T15) and 120 (T120) minutes after reperfusion. Fifteen healthy control subjects were enrolled. At T0, MCADA and IMA levels were higher in patients than in controls. MCADA decreased at T15 (median, IQR: 8.2 [7.6-9.8] IU) relative to T0 (11.25 [10-13.5] IU, p<0.01) and remained low at T120. DPPIV decreased at T15 (0.9 [0.7-1.1] AU) relative to T0 (1.05 [0.99-1.48] AU; p<0.01) and remained low at T120. IMA level increased only at T120. MCADA and DPPIV were correlated. Our findings are that MCADA and DPPIV decreased rapidly after angioplasty, suggesting that both catalysts are early markers of reperfusion.

Conclusion: MCADA and DPPIV are sensitive and early markers of ischaemia-reperfusion process during PTCA.