Gene expression profiling in endothelial precursor cells of patients protected from microvascular complications

In this study, we examined the impact of modulating the TGF-β/PAI-1 axis in CD34+ cells function from diabetic patients and controls. Using gene array studies, we found that diabetics, protected from microvascular complications despite suboptimal glycemic control, had reduced level of TGF- β1 and PAI-1 transcripts in their CD34+ cells compared to age, sex, duration and degree of glycemic control -matched diabetics with microvascular complications. Treatment with neutralizing antibody to TGF- β1 in murine hematopoietic stem cells (HSC) enhanced in vivo repopulation potential of these cells in bone marrow transplantation; reduced the time required for cell division of single cells, increased survival of the progenitor cells and reduced TGF-β1 expression. TGF- β1 phosphorodiamidate morpholino oligomers (PMO) treatment reduced PAI-1 mRNA expression in diabetic (p<0.01) and non-diabetic (p=0.05) CD34+ cells. Inhibition of PAI-1 promoted CD34+ cell proliferation and migration in vitro.Targetting TGFβ-1/PAI-1 system offers a promising therapeutic strategy for restoring vascular reparative function in diabetic CD34+ cells and hematopoietic stem cells, enhancing key functions needed for cell therapy. Peripheral blood from either age matched controls (n=5), diabetics with long standing poorly controlled diabetes and no microvascular complications (n=4), and diabetics with long-standing poorly controlled diabetes with severe microvascular complications (n=5) was obtained and CD34+ cells were isolated. RNA was extracted followed by AffyNugen amplification, and the cDNA was probed to Human RSTA Affymetrix 2.0 chip