Nerve growth factor expression in astrocytoma and cerebrospinal fluid: a new biomarker for prognosis of astrocytoma / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Recent studies have discovered that nuclear translocation of nerve growth factor (NGF) and its receptor fragments function differently from the traditional model. This study aimed to uncover the nuclear expression of NGF in astrocytoma and its biological significance.</p><p><b>METHODS</b>Ninety-four paraffin-embedded astrocytoma specimens were subjected to immunohistochemical (IHC) and hemotoxylin & eosin (HE) staining. Preoperative cerebrospinal fluid (CSF) specimens and intraoperative snap-frozen astrocytoma tissues were assayed for NGF expression by ELISA and Western blotting. The outcome of patients who contributed samples was tracked. Each ten tissue samples from patients with traumatic brain injury who had received decompression surgery and CSF samples from patients undergoing spinal anesthesia but with no history of nervous system disease were taken as control.</p><p><b>RESULTS</b>NGF-positive immunoreactive products were distributed in both the cytoplasm and nucleus of astrocytoma, but were only located in the cytoplasm of traumatic brain injury (TBI) tissue. NGF nuclear-positive rate (NPR) of grades III - IV astrocytomas (70.0%) was higher than that of grades I - II astrocytoma (28.6%, P < 0.05). NGF-NP expression positively correlated with the NGF concentration in cerebrospinal fluid (CSF) (r = 0.755, P < 0.01). Kaplan-Meier survival analysis indicated that the median survival time was 25 months for NGF-NP astrocytoma grade I - II patients and 42 months in NGF nuclear negative (NGF-NN) astrocytoma grade I - II patients (P < 0.05). In astrocytoma III - IV patients, the median survival was 7 months for NGF-NP patients and 24 months for NGF-NN patients (P < 0.01). Two types of NGF with molecular weights of 13 and 36 kDa were present in astrocytoma, but only the 36 kDa NGF was found in the CSF. NGF expression elevated as the malignancy increased.</p><p><b>CONCLUSIONS</b>NGF-NP expression and NGF level in CSF were significant prognostic factors in astrocytoma patients. Because of the easy access of CSF, it may be developed as an index for early diagnosis and surveillance of astrocytoma.</p>

A novel biosynthetic hybrid scaffold seeded with olfactory ensheathing cells for treatment of spinal cord injuries / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Implantation of tissue-engineered scaffolds is one of the most promising therapeutic strategies for inducing nerve regenerations following spinal cord injuries. In this paper, we report a novel bioengineered hybrid scaffold comprised of three major extracellular matrix (ECM) proteins.</p><p><b>METHODS</b>ECM-scaffolds (ECM-S) were prepared by gelling fibrinogen, fibronectin and laminin using fresh rat plasma. Olfactory ensheathing cells (OECs) were isolated from fresh rat olfactory mucosa, purified under differential adhesion, and assessed by immunofluorescent staining. OECs were seeded onto ECM-S and cultured. The effects of the scaffolds on the seeded cells were detected using the immunofluorescent staining, Western blotting, scanning electron microscopy and transmission electron microscopy.</p><p><b>RESULTS</b>Tissue-engineered ECM-S could be easily molded into mat-like or cylindrical shapes and gelled by addition of fresh plasma. Observations by electron microscopy show that the ECM-S forms a stable three-dimensional porous network. Studies on the effects of the ECM-S on the biological behaviors of OECs in vitro indicate that the scaffold can promote OEC adhesion, proliferation and process extensions. Additionally, OECs seeded on the scaffold maintained the expression of nerve growth factor, matrix metalloproteinase-3 and matrix metalloproteinase-9.</p><p><b>CONCLUSION</b>We developed a biosynthetic hybrid gel which could be used as a scaffold for OEC transplantation; this gel can promote nerve regeneration following spinal cord injuries.</p>

The mitosis and immunocytochemistry of olfactory ensheathing cells from nasal olfactory mucosa / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To culture olfactory ensheathing cells (OECs) of rats in vitro and to investigate its morphology, mitosis and immunocytochemistry, and to explore if the OECs could be a new donation for transplantation.</p><p><b>METHODS</b>OECs were harvested from olfactory mucosa of Sprague Dawley rats based on the differing rates of attachment of the various cell types, followed by glial fibrillary acidic protein (GFAP), nerve growth factor (NGF), anti-low affinity receptor for NGF (NGFRp75), brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT-3) and S-100 immunocytochemistry. The morphological changes and mitosis were observed under a phase contrast microscope at different culture time.</p><p><b>RESULTS</b>Three morphologically distinct types of cells, bipolar, multipolar and flat morphology were present in the primary culture of adult rat olfactory mucosa. Mitosis was characterized by a retraction of all processes, forming a sphere that divided into spherical daughter cells, the daughter cells sent out their processes. The OECs were immunoreactive for GFAP, NGFRp75, S-100, NGF, BDNF and NT-3.</p><p><b>CONCLUSIONS</b>The OECs from nasal olfactory mucosa cultivated in the medium with fetal bovine serum could survive, divide, differentiate, and express the neurotrophin. It may become an accessible source for autologous grafting in spinal cord injury.</p>