Decreased expression of complement regulatory proteins, CD55 and CD59, on peripheral blood leucocytes in patients with type 2 diabetes and macrovascular diseases.
BACKGROUND
Macro- and microvascular diseases are the leading cause of morbidity and mortality in diabetic patients, but their mechanisms remain unclear. Recent reports provide evidence that the levels of CD55 and CD59 are decreased in diabetic microvascular diseases. However, very little is known about the levels of CD55 and CD59, the relationship between them and carotid artery intima-media thickness, and the effects of statins on CD55 and CD59 in diabetic macrovascular diseases.


METHODS
The mean fluorescence intensity (MFI) of CD55 and CD59 expression on peripheral blood leucocyte subsets (lymphocytes, monocytes and neutrophils) was studied using flow cytometry, and carotid artery intima-media thickness was measured using B-mode ultrasonography in 23 healthy subjects (controls), 19 patients with type 2 diabetes (T2DM), and 43 patients with type 2 diabetes and macrovascular diseases (T2DM-M). The patients with T2DM-M were assigned to two subgroups based on whether statins were used: group with statins (n = 23) and group without statins (n = 20).


RESULTS
Compared with the controls and T2DM, the MFI of CD55 positive neutrophils was significantly lower in T2DM-M (P = 0.049 vs controls and P = 0.033 vs T2DM); similarly, the MFI of CD59 positive monocytes was also lower in T2DM-M (P = 0.038 vs controls and P = 0.043 vs T2DM). The MFI of CD59 positive neutrophils in T2DM-M was lower than in T2DM (P = 0.032). The levels of CD55 and CD59 were negatively associated with age and blood pressure (r = -0.245 - -0.352, P = 0.041 - 0.003), but not acute-phase reactants and carotid artery intima-media thickness. The levels of CD55 and CD59 increased after treatment with statins, but the results were not significantly different (P > 0.05).


CONCLUSIONS
CD55 and CD59 expressions on peripheral blood leucocytes are decreased in T2DM patients with macrovascular diseases. The results suggest that the decreased levels of complement regulatory proteins might play an important role in diabetic macrovascular diseases.
Ma
Xi-wen
XW
Department of Geriatrics, Beijing Tongren Hospital, Capital Medical University, Beijing 100730, China.
Chang
Zhi-wen
ZW
Qin
Ming-zhao
MZ
Sun
Ying
Y
Huang
Hui-lian
HL
He
Yan
Y
D000368:Aged; D000369:Aged, 80 and over; D018958:CD55 Antigens / Q000276:immunology*; D018957:CD59 Antigens / Q000276:immunology*; D003924:Diabetes Mellitus, Type 2 / Q000276:immunology*; D003925:Diabetic Angiopathies / Q000276:immunology*; D005260:Female; D005434:Flow Cytometry; D005786:Gene Expression Regulation; D006801:Humans; D007962:Leukocytes / Q000276:immunology*; D008297:Male; D008875:Middle Aged
D018958:CD55 Antigens; D018957:CD59 Antigens