UMR_S 1076, INSERM, Aix Marseille Univ., Marseille, France.
CERIMED, Aix Marseille Univ., Marseille, France.
J Nucl Med. 2016 Nov;57(11):1798-1804. doi: 10.2967/jnumed.115.170308. Epub 2016 Sep 8.
Endothelial colony-forming cells (ECFCs) are promising candidates for cell therapy of ischemic diseases, as less than 10% of patients with an ischemic stroke are eligible for thrombolysis. We previously reported that erythropoietin priming of ECFCs increased their in vitro and in vivo angiogenic properties in mice with hindlimb ischemia. The present study used SPECT/CT to evaluate whether priming of ECFCs with erythropoietin could enhance their homing to the ischemic site after transient middle cerebral artery occlusion (MCAO) followed by reperfusion in rats and potentiate their protective or regenerative effect on blood-brain barrier (BBB) disruption, cerebral apoptosis, and cerebral blood flow (CBF).
Rats underwent a 1-h MCAO followed by reperfusion and then 1 d after MCAO received an intravenous injection of either PBS (control, n = 10), PBS-primed ECFCs (ECFC, n = 13), or erythropoietin-primed ECFCs (ECFC, n = 10). ECFC homing and the effect on BBB disruption, cerebral apoptosis, and CBF were evaluated by SPECT/CT up to 14 d after MCAO. The results were expressed as median ± interquartile range for ipsilateral-to-contralateral ratio of the activity in middle cerebral artery-vascularized territories in each hemisphere. Histologic evaluation of neuronal survival and astrocytic proliferation was performed on day 14.
Erythropoietin priming increased homing of ECFCs to the ischemic hemisphere (ECFC, 111.0% ± 16.0%; ECFC, 146.5% ± 13.3%). BBB disruption was significantly reduced (control, 387% ± 153%; ECFC, 151% ± 46% [P < 0.05]; ECFC, 112% ± 9% [P < 0.001]) and correlated negatively with ECFC homing (Pearson r = -0.6930, P = 0.0002). Cerebral apoptosis was significantly reduced (control, 161% ± 10%; ECFC, 141% ± 9% [P < 0.05]; ECFC,118% ± 5% [P < 0.001]) and correlated negatively with ECFC homing (r = -0.7251, P < 0.0001). CBF was significantly restored with ECFCs and almost totally so with erythropoietin priming (control, 72% ± 2%; ECFC, 90% ± 4% [P < 0.01]; ECFC, 99% ± 4% [P < 0.001]) and correlated positively with ECFC homing (r = 0.7348, P < 0.0001). Immunoblocking against the CD146 receptor on ECFCs highlighted its notable role in ECFC homing with erythropoietin priming (ECFC, 147% ± 14%, n = 4; ECFC with antibody against CD146, 101% ± 12%, n = 4 [P < 0.05]).
Priming with erythropoietin before cell transplantation is an efficient strategy to amplify the migratory and engraftment capacities of ECFCs and their beneficial impact on BBB disruption, apoptosis, and CBF.
评估红细胞生成素（EPO）预处理能否增强内皮祖细胞（ECFC）在短暂性大脑中动脉闭塞（MCAO）后继发性再灌注后的归巢能力，并增强其对血脑屏障（BBB）破坏、脑凋亡和脑血流（CBF）的保护或再生作用。
MCAO 后大鼠再灌注 1 天，然后接受 PBS（对照组，n=10）、PBS 预处理的 ECFC（ECFC，n=13）或 EPO 预处理的 ECFC（ECFC，n=10）静脉注射。通过 SPECT/CT 评估 ECFC 归巢及其对 BBB 破坏、脑凋亡和 CBF 的影响，直至 MCAO 后 14 天。结果以每侧大脑中动脉血管化区域活性的半侧/对侧比值的中位数（四分位距）表示。在第 14 天进行神经元存活和星形胶质细胞增殖的组织学评估。
EPO 预处理可增加 ECFC 向缺血半球的归巢（ECFC，111.0%±16.0%；ECFC，146.5%±13.3%）。BBB 破坏明显减少（对照组，387%±153%；ECFC，151%±46%[P<0.05]；ECFC，112%±9%[P<0.001]），与 ECFC 归巢呈负相关（Pearson r=-0.6930，P=0.0002）。脑凋亡明显减少（对照组，161%±10%；ECFC，141%±9%[P<0.05]；ECFC，118%±5%[P<0.001]），与 ECFC 归巢呈负相关（r=-0.7251，P<0.0001）。ECFC 可显著恢复 CBF，EPO 预处理几乎可完全恢复 CBF（对照组，72%±2%；ECFC，90%±4%[P<0.01]；ECFC，99%±4%[P<0.001]），与 ECFC 归巢呈正相关（r=0.7348，P<0.0001）。用针对 ECFC 上的 CD146 受体的免疫阻断剂强调了其在 EPO 预处理的 ECFC 归巢中的显著作用（ECFC，147%±14%，n=4；用针对 CD146 的抗体处理的 ECFC，101%±12%，n=4[P<0.05]）。
细胞移植前用 EPO 预处理是一种有效的策略，可以增强 ECFC 的迁移和植入能力，以及它们对 BBB 破坏、凋亡和 CBF 的有益影响。
