Abstract 402: Human CD271-positive Adipose Derived Stem Cells are the Angiogenic Subset Decreased by Donor Insulin Resistance

Abstract

Introduction: Type 2 diabetes mellitus (T2DM) is an important risk factor for cardiovascular diseases (CVDs). Recently, cell therapy using adipose-derived stem cells (ADSCs) has emerged as an attractive therapy for severe CVDs because of their angiogenic potentials. However, whether and how T2DM would impair human ADSC angiogenic capacity is still uncertain. We previously reported that CD31 - CD34 + CD271 + ADSCs (CD271 + ADSCs) were specifically decreased in adipose tissue of T2DM patients. Therefore, we aimed to investigate the angiogenic capacity of CD271 + ADSCs. Furthermore, we evaluate which patients’ parameters regard as T2DM would decrease the amount of CD271 + ADSCs. Methods and Results: Human CD45 - CD34 + CD31 - ADSCs were obtained from subcutaneous adipose tissue of healthy donors, separated into CD271 + and CD271 - subsets by FACS, and cultured. Both subsets of ADSCs were assessed gene expression profile by microarray. Microarray analysis and validation PCR elucidated that PI3K/Akt/mTOR pathway was significantly up-regulated in CD271 + ADSCs compared to in CD271 - ADSCs. ( p < 0.05). Then, we compared in vivo angiogenic capacity in xenograft experiments of nude mice subjected to hindlimb ischemia. Angiogenesis was evaluated histologically using perfused lectin (capillary density) at day 14. Cell therapy using CD271 + ADSCs demonstrated about 3-fold more lectin + capillaries compared to CD271 - ADSCs or PBS injection ( p < 0.005, n = 5 / group). Next, we established cultured ADSCs obtained from CD271 knock-out mice (KO-ADSCs) and compared their angiogenic capacity with those from WT mice. Consistently, KO-ADSCs demonstrated impaired in vivo angiogenic capacity ( p < 0.005, n = 5 / group). Finally, we collected 23 samples of adipose tissue obtained from CVD patients and evaluated the frequency of CD271 + ADSCs in CD45 - CD34 + CD31 - ADSCs. Among studied parameters, HOMA-IR, an index of insulin resistance, was negatively correlated with the frequency of CD271+ ADSCs ( r = -0.64, p < 0.005). Conclusions: Human CD271 + ADSCs demonstrated enhanced in vivo angiogenic capacity with higher mTOR expression. Donor insulin resistance might decrease this regenerative subset of ADSCs. These findings would be critical for development and improvement of ADSC therapy.