Human PLacental eXpanded (PLX) mesenchymal-like adherent stromal cells confer neuroprotection to nerve growth factor (NGF)-differentiated PC12 cells exposed to ischemia by secretion of IL-6 and VEGF

Abstract

Mesenchymal stem cells are potent candidates in stroke therapy due to their ability to secrete protective anti-inflammatory cytokines and growth factors. We investigated the neuroprotective effects of human placental mesenchymal-like adherent stromal cells (PLX) using an established ischemic model of nerve growth factor (NGF)-differentiated pheochromocytoma PC12 cells exposed to oxygen and glucose deprivation (OGD) followed by reperfusion. Under optimal conditions, 2 × 10⁵ PLX cells, added in a trans-well system, conferred 30-60% neuroprotection to PC12 cells subjected to ischemic insult. PC12 cell death, measured by LDH release, was reduced by PLX cells or by conditioned medium derived from PLX cells exposed to ischemia, suggesting the active release of factorial components. Since neuroprotection is a prominent function of the cytokine IL-6 and the angiogenic factor VEGF165, we measured their secretion using selective ELISA of the cells under ischemic or normoxic conditions. IL-6 and VEGF165 secretion by co-culture of PC12 and PLX cells was significantly higher under ischemic compared to normoxic conditions. Exogenous supplementation of 10 ng/ml each of IL-6 and VEGF165 to insulted PC12 cells conferred neuroprotection, reminiscent of the neuroprotective effect of PLX cells or their conditioned medium. Growth factors as well as co-culture conditioned medium effects were reduced by 70% and 20% upon pretreatment with 240 ng/ml Semaxanib (anti VEGF165) and/or 400 ng/ml neutralizing anti IL-6 antibody, respectively. Therefore, PLX-induced neuroprotection in ischemic PC12 cells may be partially explained by IL-6 and VEGF165 secretion. These findings may also account for the therapeutic effects seen in clinical trials after treatment with these cells.

Placental Stromal Cell Therapy for Experimental Autoimmune Encephalomyelitis: The Role of Route of Cell Delivery

“…The discrepancy between the significant beneficial effects after intracranial delivery compared with the marginal benefit following systemic delivery underscores the importance of the route of cell delivery. Several studies support the notion that hPSCs induce their beneficial effects locally, as bystanders, and therefore should be delivered directly to the target organ of disease []. In agreement with our findings, ICV implantation of hPSCs attenuated EAE [] and reduced the ischemic lesion size after middle cerebral artery occlusion, accompanied by a reduction of the microglial response [].…”

Isolation and characterization of canine placenta‐derived mesenchymal stromal cells for the treatment of neurological disorders in dogs

“…The observed secretory profile of cPMSCs in combination with existing MSC literature suggests the potential for use as a therapeutic; cPMSCs secreted IL‐6, IL‐8, MCP‐1, and VEGF, all paracrine factors secreted by human PMSC lines in our previous studies . IL‐6 is an immunomodulatory cytokine with demonstrated in vitro and in vivo neuroprotective capabilities . IL‐8 is another cytokine with immunomodulatory properties that also promotes angiogenesis .…”

Mesenchymal Stromal Cells from Fetal and Maternal Placenta Possess Key Similarities and Differences: Potential Implications for Their Applications in Regenerative Medicine

“…We compared maternal MSC-like cells (PLX-PAD) and two different fetal-derived cells known as PLX-R18 [36][37][38][39][40] and a well-characterized MSC population from the amniotic membrane [41]. Placental expanded (PLX) are of a good manufacturing practice (GMP)-grade clinical investigational product that are prepared using a 3-dimensional (3D) bioreactor-based cell growth platform.…”