Abstract
The ability to culture neural progenitor cells from the adult human brain has provided an exciting opportunity to develop and test potential therapies on adult human brain cells. To achieve a reliable and reproducible adult human neural progenitor cell (AhNPC) culture system for this purpose, this study fully characterized the cellular composition of the AhNPC cultures, as well as the possible changes to this in vitro system over prolonged culture periods. We isolated cells from the neurogenic subventricular zone/hippocampus (SVZ/HP) of the adult human brain and found a heterogeneous culture population comprised of several types of post-mitotic brain cells (neurons, astrocytes, and microglia), and more importantly, two distinct mitotic cell populations; the AhNPCs, and the fibroblast-like cells (FbCs). These two populations can easily be mistaken for a single population of AhNPCs, as they both proliferate under AhNPC culture conditions, form spheres and express neural progenitor cell and early neuronal markers, all of which are characteristics of AhNPCs in vitro. However, despite these similarities under proliferating conditions, under neuronal differentiation conditions, only the AhNPCs differentiated into functional neurons and glia. Furthermore, AhNPCs showed limited proliferative capacity that resulted in their depletion from culture by 5–6 passages, while the FbCs, which appear to be from a neurovascular origin, displayed a greater proliferative capacity and dominated the long-term cultures. This gradual change in cellular composition resulted in a progressive decline in neurogenic potential without the apparent loss of self-renewal in our cultures. These results demonstrate that while AhNPCs and FbCs behave similarly under proliferative conditions, they are two different cell populations. This information is vital for the interpretation and reproducibility of AhNPC experiments and suggests an ideal time frame for conducting AhNPC-based experiments.
Highlights
The existence of adult neural stem cells in the rodent brain was reported in the 1960s [1,2] and by the early 1990s, they were successfully isolated, propagated and differentiated into neurons in vitro [3]
We studied the proliferating cell types grown from adult human brain tissue to compare their properties and determine whether fibroblast-like cells (FbCs) and adult human neural progenitor cell (AhNPC) are two distinct populations or arise from a common source
We demonstrate the relatively limited proliferative ability of the AhNPCs compared to the FbCs and suggest a time frame in which AhNPC experiments should be conducted for accurate interpretation of in vitro experiments of adult human neurogenesis
Summary
The existence of adult neural stem cells in the rodent brain was reported in the 1960s [1,2] and by the early 1990s, they were successfully isolated, propagated and differentiated into neurons in vitro [3]. A number of reports showed that AhNPCs were capable of being cultured in vitro from both autopsy and biopsy human brain tissue [8,9,10,11,12,13,14,15,16]. Most of these studies utilized the neurosphere (NS) culture method [3,17], and provided evidence for self-renewal through 5-bromo-2-deoxyuridine (BrdU) incorporation studies [8] and single AhNPC clonal expansion studies [10,16]. It is possible that these FbCs are, another source of NPCs in the brain [22]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
