School of Pharmacy Institute for Drug Research, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel.
School of Pharmacy Institute for Drug Research, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel.
Cytotherapy. 2018 Feb;20(2):245-261. doi: 10.1016/j.jcyt.2017.11.008. Epub 2017 Dec 20.
Human umbilical cord blood (HUCB) is an important source of stem cells for therapy of hematopoietic disorders and is a potential therapy for various neurological disorders, including traumatic brain injury (TBI). The expression of nerve growth factor (NGF) and its receptors TrkA, p75 and α9β1 integrin on an HUCB CD45 pan-hematopoietic subpopulation was investigated in the context of its neurotherapeutic potential after TBI.
NGF and its receptors were detected on CD45 cells by reverse transcriptase polymerase chain reaction, flow cytometry analysis and confocal microscopy. CD45 cells were stimulated by TBI brain extracts, and NGF levels were measured by enzyme-linked immunosorbent assay. TBI mice were divided into six groups for xenogeneic intravenous transplantation, 1 day post-trauma, with 1 × 10 CD45 cells untreated or treated with the anti-NGF neutralizing antibody K252a, a TrkA antagonist; VLO5, an α9β1 disintegrin; or negative (vehicle) and positive (NGF) controls.
The HUCB CD45 subpopulation constitutively expresses NGF and its receptors, mainly TrkA and p75 and minor levels of α9β1. In vitro experiments provided evidence that trauma-related mediators from brain extracts of TBI mice induced release of NGF from HUCB CD45 cell cultures. HUCB CD45 cells induced a neurotherapeutic effect in TBI mice, abrogated by cell treatment with either anti-NGF antibody or K252a, but not VLO5.
These findings strengthen the role of NGF and its TrkA receptor in the HUCB CD45 subpopulation's neurotherapeutic effect. The presence of neurotrophin receptors in the HUCB CD45 pan-hematopoietic subpopulation may explain the neuroprotective effect of cord blood in therapy of a variety of neurological disorders.
人类脐血（HUCB）是治疗血液系统疾病的重要干细胞来源，也是治疗包括创伤性脑损伤（TBI）在内的多种神经疾病的潜在疗法。本研究旨在探讨 HUCB CD45 泛造血亚群在 TBI 后的神经治疗潜能，并检测其神经生长因子（NGF）及其受体 TrkA、p75 和 α9β1 整联蛋白的表达情况。
通过逆转录聚合酶链反应、流式细胞术分析和共聚焦显微镜检测 CD45 细胞上的 NGF 及其受体。用 TBI 脑提取物刺激 CD45 细胞，用酶联免疫吸附试验检测 NGF 水平。TBI 小鼠分为六组，于创伤后 1 天进行异种静脉移植，每组 1×10 CD45 细胞未经处理或用抗 NGF 中和抗体 K252a、TrkA 拮抗剂；VLO5，一种α9β1 整联蛋白抑制剂；或阴性（载体）和阳性（NGF）对照处理。
HUCB CD45 亚群持续表达 NGF 及其受体，主要是 TrkA 和 p75，还有少量的α9β1。体外实验表明，TBI 小鼠脑提取物中的创伤相关介质诱导 HUCB CD45 细胞培养物中 NGF 的释放。HUCB CD45 细胞在 TBI 小鼠中诱导了神经治疗作用，用抗 NGF 抗体或 K252a 处理细胞可阻断该作用，但用 VLO5 处理则无作用。
这些发现加强了 NGF 及其 TrkA 受体在 HUCB CD45 亚群神经治疗作用中的作用。HUCB CD45 泛造血亚群存在神经营养因子受体，可能解释了脐带血在治疗多种神经疾病中的神经保护作用。
