Circulation of CD34+ progenitor cell populations in patients with idiopathic dilated and ischaemic cardiomyopathy (DCM and ICM)

Aims This study aimed at analysing the endogenous stem cell circulation in patients suffering from idiopathic dilated cardiomyopathy (DCM) and ischaemic cardiomyopathy (ICM). Methods and results Cytokines in peripheral blood were analysed using enzyme-linked immunosorbent assay and circulating CD34+ stem cell populations (CD34+CD133+, CD34+CD31+, CD34+CXCR-4+) were measured by flow cytometry in DCM patients ( n = 25), ICM patients ( n = 15), and controls ( n = 10). Explanted DCM ( n = 5), ICM ( n = 4) and normal hearts ( n = 5) were analysed for the expression of several homing factors [stromal cell-derived factor-1 (SDF-1), Stem cell factor (SCF), HIF-1a, vascular cell adhesion molecule (VCAM), and Hepatocyte growth factor] by quantitative real-time polymerase chain reaction (PCR). SDF-1 was significantly elevated and positively correlated with brain natriuretic peptide (BNP) in peripheral blood of DCM and ICM patients showing the same New York heart association- (NYHA) class. In DCM patients circulating CD34+ cell populations were significantly increased in comparison to ICM patients and controls. mRNA of SDF-1, SCF, HIF-1a, and VCAM related to glyceraldehyde-3-phosphate dehydrogenase was significantly upregulated in ICM hearts when compared with DCM hearts and controls. Conclusion Myocardial homing factors are upregulated in ICM when compared with DCM hearts. Reduced homing of stem cells might therefore explain the increased number of CD34+ cells in DCM patients. These findings may open a new insight into the pathology and the treatment of idiopathic DCM.