Heparan Sulfate Proteoglycans as Markers in Human Neural Progenitor Cell Line Short-Term Lineage Differentiation

Abstract Heparan sulfate proteoglycans (HSPGs) are major constituents of the neuronal niche and have been demonstrated to be expressed in the developing brain and to contribute to multiple aspects of neurogenesis, including neural progenitor cell proliferation, differentiation, and synaptogenesis. However, their roles in human stem cell neural differentiation are still under exploration. This study utilised three human cell lines, first expanded under basal culture conditions then differentiated towards neuronal (SH-SY5Y human neuroblastoma cells), astrocyte (ReNcell CX human neural progenitor cells) and mixed neural cultures (ReNcell VM human neural progenitor cells). The cells were characterised in basal and differentiated states for calcium signalling activity and via Q-PCR, Western Blotting, and immunocytochemistry (ICC) analyses. The results showed that the HSPG core protein and heparan sulfate (HS) biosynthesis enzyme profiles differed between the different neural lineage cultures, as well as demonstrated distinct correlations with neural specific lineage markers. Surface-bound glypican-1 (GPC1), GPC2, and GPC4 were found to be associated with neuronal lineage differentiation while GPC6 and syndecan-3 (SDC3) were observed to be upregulated in astrocyte differentiation. Modulation of ReNcell VM mixed neural cultures with HS-binding neuroregulatory growth factors brain-derived neurotrophic factor (BDNF) and platelet-derived growth factor (PDGF) produced cultures suppressed glial lineage differentiation potential while modifying HS chain sulfation. Overall, the findings from this study provide evidence of HSPGs and HS GAGs as key regulators of human neural lineage differentiation and specification and targeting these HSPGs may allow for the better isolation of human neural lineage specific cell populations.