This work was supported by the Brain Research Program through the National Research Foundation (NRF), funded by the Korean Ministry of Science, ICT, and Future Planning (Grants NRF-2015M3C7A1028790); and by a grant from the Korea Health Technology R&amp;D Project through the Korea Health Industry Development Institute (KHIDI), funded by the Ministry of Health &amp; Welfare, Republic of Korea (HI14C3347).

1. Preparation of Materials and Culture Medium
<ol>
	<li>For the dissection and dissociation of the SCZ, wrap the brain matrix, double-edged razor blade, and forceps with aluminum foil, and then sterilize them by autoclaving.</li>
	<li>Prepare 50 ml of cold PBS buffer to wash the whole mouse brain.</li>
	<li>Set up a dissection microscope and prepare the surgical tools required for the dissection of the brain (autoclaved scissors and forceps) and the isolation of the SCZ (1 ml syringe, 30 G needle, brain matrix, and fine forceps).</li>
	<li>Preparation of N2 Medium:
	<ol>
		<li>Prepare F-12/DMEM (+L-glutamin, +sodium bicarbonate) medium with 2% B27, 1% N2 supplements, and 1% Penicillin-Streptomycin. 
		Note: The growth medium consists of N2 medium and growth factors (20 ng/mL purified epidermal growth factor (EGF) and 20 ng/mL basic fibroblast growth factor (bFGF2)).</li>
	</ol>
	</li>
	<li>Prepare a digestion buffer (40 unit/ml papain, 2.4 unit/ml dispase II, and 2% penicillin-streptomycin in PBS) for tissue digestion.</li>
	<li>Preparation of Coating Plate and Coverslip:
	<ol>
		<li>Prepare poly-L-ornithine (PLO; 0.01%) and laminin (10 &#181;g/ml dissolved in DH2O). To coat 6-well plates for the maintenance of SCZ-aNSCs as a monolayer or 18 mm coverslips for immunostaining, incubate them with PLO overnight at 4 &#176;C. Then wash them 3 times with DH2O. Allow the plates and coverslips to dry after the last washing.</li>
		<li>Next, incubate the plates with laminin overnight at 4 &#176;C. Then, wash them 3 times with DH2O. 
		Caution: Do not dry the laminin, which will affect cell attachment. 
		Note: The coating solutions can be reused 3 times.</li>
	</ol>
	</li>
</ol>
2. Isolation and Dissociation of the Adult SCZ
<ol>
	<li>Prior to culture preparation, place the brain matrix and double-edged razor on ice. 
	Note: Do not freeze the brain matrix, because the brain could attach to it.</li>
	<li>Sacrifice a mouse (8 weeks old) by CO2 asphyxiation or cervical dislocation.
	<ol>
		<li>Cut off the head with sharp scissors after spraying 70% ethanol. To immobilize the head, hold both sides of the head tightly. Cut the skin with scissors at the midline in a caudal-rostral direction. This promotes the complete removal of the skin from the skull.</li>
		<li>Remove the caudal part of skull (posterior to lambda) first, and then insert the forceps between the skull and brain at the dorsal midline position. Grab the left (or right) parietal bone and carefully peel it off. Repeat this procedure for the removal of the other parietal bone. 
		Note: Disconnection of optic nerve and removal of the meninges from the brain make it easier to detach the brain from the skull.</li>
		<li>Transfer the brain to cold PBS buffer (25 ml) and rinse it twice to remove excess blood.</li>
	</ol>
	</li>
	<li>Place the brain into the brain matrix on ice and make coronal cuts to obtain 1 mm thick slices. Transfer the brain slices (1 mm) containing the SCZ regions that are located in the posterior part of the brain to a cold PBS in a 35 mm plastic petri dish. 
	Caution: In order to obtain a parallel plane of coronal sections, ensure that the brain fissure is placed in the midline of the brain matrix; it is critical to avoid unnecessary variations in the sections. 
	Note: Obtain brain slices at 2-3 mm posterior to bregma; this allows the separation of the SCZ from the SVZ.</li>
	<li>Under the dissecting microscope with a low magnification, micro-dissect the SCZ from the white matter area of the cortex and hippocampus with a bent 30G needle6,9. Then, remove the cortex regions above the SCZ. Place the dissected SCZ region from the slices into a 35 mm plastic petri dish on ice without cold PBS. 
	Note: Contamination of extra regions containing mature neurons could affect the viability of aNSCs and neurosphere formation because they undergo cell death in aNSC culture conditions.</li>
	<li>Using a bent 30 G needle, immediately chop the dissected tissues into small pieces. 
	Note: If a longer time is required for dissecting the SCZ tissue, immerse the dissected tissues in cold PBS before chopping.</li>
	<li>Re-suspend the chopped tissue with 1 ml of digestion buffer, transfer the tissue to a 15 ml tube containing 2 ml of digestion buffer, and incubate it for 30 min in a 37 &#176;C water bath. 
	Note: Shake the tube every 10 min to mix well.</li>
</ol>
3. Subcallosal Zone-derived Adult Neural Stem Cell Culture
<ol>
	<li>Tap the tube mildly to dissociate the digested tissue, and then centrifuge the tube at 145 x g for 5 min. Discard the supernatant, re-suspended the digested tissue with 1 mL of pre-warmed N2 medium to wash out the digestion buffer, and gently pipet the sample solution a maximum of 5 times using a P1000 pipette. 
	Note: Over-triturating with a narrow pipet tip can diminish cell viability and subsequent growth.</li>
	<li>Centrifuge the tube at 145 x g for 5 min. After discarding the supernatant, re-suspend the cell pellet in 1 ml of N2 medium.</li>
	<li>Prepare 1 ml of N2 medium in a non-coated 6-well plate and add 1 ml of the suspended cells to make a final volume of 2 ml.</li>
	<li>Add EGF (20 ng/ml) and bFGF (20 ng/ml) into each well. Gently shake the 6-well culture dish by hand to mix the added growth factors with the plated cells. Keep the 6-well plate in a 37 &#176;C and 5% CO2 incubator.</li>
	<li>Add EGF (20 ng/ml) and bFGF (20 ng/ml) to each well every day for 8 days. Every third day, add 200 &#181;l of N2 media to maintain the approximate 2 ml volume of the medium.</li>
</ol>
4. Passaging of NSCs as Neurospheres and to Monolayer Cultures
<ol>
	<li>Gather the neurospheres and transfer them to a new 15 ml conical tube. 
	Note: The number of neurospheres (&#62;50 &#181;m diameter) per well from the SCZ of a single mouse brain was 64.3 &#177; 7.31, which was less than that of the SVZ (190.5 &#177; 6.33)9.</li>
	<li>Incubate the neurospheres with 0.5 ml of dissociation buffer for 5 min in a 37 &#176;C water bath to dissociate the neurospheres into single cells. Primary neurospheres can be dissociated into single cells and maintained over several passages as neurosphere or monolayer cultures. 
	Note: Expanding SCZ-aNSCs as a monolayer is superior to neurospheres because SCZ-aNSCs can be passaged &#62;10 times in a monolayer culture format, but &#60;5 times in a neurosphere culture format. 
	Caution: SCZ-aNSCs exhibit strong aggregation, and it is difficult to dissociate them into single cells. Thus, the neurosphere culture format is not recommended for routine cell expansion.</li>
	<li>Gently pipet the sample solution up and down with a P1000 pipette less than 5 times and centrifuge the tube at 145 x g for 5 min. Discard the supernatant and re-suspend the neurospheres with 1 ml of N2 medium. 
	Note: Over triturating with a narrow pipette tip can diminish cell viability and subsequent growth.</li>
	<li>To count the cells, make a 1:1 mixture of the cell suspension (10 &#181;l) and the 0.4% trypan blue solution, and then count the number of live cells on a hematocytometer. After coating a 6-well plate with PLO/laminin, plate the cells at 2.5 x 105 cells/ml with 2 ml of N2 medium for each well. 
	Note: Changes in cell density can affect their condition and differentiation potential.</li>
	<li>Maintain the SCZ-aNSCs with a daily treatment of growth factors (2 ml, 20 ng/ml) for 5 days, and them passage them.</li>
</ol>
5. Differentiation of Subcallosal Zone-derived Adult Neural Stem Cells
<ol>
	<li>Plate aNSCs onto a PLO/Laminin-coated 18 mm coverslip with 1 x 105 cells/ml in 1 ml N2 with growth factors (20 ng/ml) for differentiation of the SCZ-aNSCs.</li>
	<li>The next day, when the cells are firmly attached to the coverslip, exchange the growth medium with N2 to remove the growth factors.</li>
	<li>After 6 days, wash the differentiated cells with 1 ml of PBS to remove cell debris and fix them for immunostaining. 
	Note: BrdU can be incorporated into the newly-synthesized DNA of proliferating cells. Therefore, if desired, BrdU (10 &#181;g/ml) can be added to live cells before the fixation of cells.</li>
</ol>
6. Immunostaining Adult Neural Stem Cells and Differentiated Progenitors
<ol>
	<li>For immunostaining, wash the cells with PBS and fix them with 4% PFA for 20 min at room temperature. 
	Caution: PFA is highly toxic; avoid contact with the skin and eyes.</li>
	<li>Remove the 4% PFA, rinse the fixed cells with PBS 3 times, and then store them at 4 &#176;Cuntil they are needed for immunostaining.</li>
	<li>Incubate the cells on the coverslip with blocking solution (3% bovine serum albumin and 0.1% Triton X-100 in 1x PBS) for at least 30 min at room temperature.</li>
	<li>Prepare the primary antibodies in fresh blocking solution and incubate the samples overnight at 4 &#176;C.
	<ol>
		<li>Immunostaining the aNSCs
		<ol>
			<li>Stain the aNSCs using anti-Nestin and anti-BrdU antibodies. Before fixation, add 20 &#181;g of BrdU to the aNSCs and incubate them for 2 h. Perform the denaturing step using 2 N HCl for 20 min at 37 &#176;Cbefore performing the blocking step.</li>
		</ol>
		</li>
		<li>Immunostaining the differentiated progenitors:
		<ol>
			<li>Use anti-O4, anti-bIII-tubulin, and anti-glial fibrillary acidic protein (GFAP) antibodies to label the differentiated progenitors.</li>
		</ol>
		</li>
	</ol>
	</li>
	<li>Wash the samples with PBS 3 times and incubate them with secondary antibodies conjugated to fluorescent dyes (1:500) in blocking solution for 30 min at room temperature. Then, wash the samples 3 times with PBS. 
	Note: Use secondary antibodies that match the hosts of the primary antibodies. Hoechest33343 (1:2,000) is used for nuclear staining.</li>
	<li>Add mounting solution to a slide glass and proceed with mounting. Observe and image the sample on a confocal microscope at multiple wavelengths: FITC (488 nm), Cy3 (543 nm), Cy5 (647 nm), and Hoechest33343 (405 nm).</li>
</ol>

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The authors declare no conflicts of interest.

This paper describes a detailed protocol to generate NSCs from the adult mouse SCZ and to maintain them for various applications. There are three critical steps for establishing the in vitro culture system needed to purify and expand SCZ-NSCs. First, it is important to ensure that the SCZ region is precisely dissected out from other potential neurogenic regions (Figure 1B). Thick and precise sections containing the SCZ regions were obtained with a 1 mm interval brain matrix, and then a fine need...

NSCs have characteristics of self-renewal and multiple-lineage differentiation. To confirm these properties, a neurosphere culture system has widely been used. The neurosphere culture system was developed in the early 1990s and served as a standard stem cell culture system1. Depending on self-renewal potency, NSCs continuously proliferate and generate a cell mass in a suspension culture. The number of cells and the size of the neurosphere are considered to be closely associated with the proliferation properties of the NSCs. Monolayer cultures are also widely used for the maintenance and differentiation of NSCs. Compared to the neurosphere culture, the monolayer culture system provides better homogenous maintenance and expansion of NSCs2. These two well-developed culture systems have contributed to the characterization of aNSCs in vitro. 
NSCs reside in different brain regions, such as the subventricular zone (SVZ) of the lateral ventricle and the subgranular zone (SGZ) of the hippocampus3-5. The subcallosal zone (SCZ) of the caudal subcortical white matter is recognized as a novel neurogenic region6-8. It was recently reported that the SCZ-aNSCs have therapeutic potential in traumatic brain injury9. Compared to other neurogenic regions, the SCZ resides along the subcortical white matter. In the human brain, subcortical white matter occupies a larger region than in the mouse brain10. Therefore, an understanding of the characteristics of SCZ-aNSCs using an in vitro culture system is important in order to promote the potential use of these cells for neural regeneration. Precise dissection of the desired brain region is required to rule out possible contamination by unwanted regions containing active or quiescent NSCs. For instance, aNSCs in non-neurogenic regions can be activated and produce new neural cells in injured brains or during in vitro culturing11. To obtain NSCs from the SCZ, cells were collected from brain slices containing the SCZ. Then, a careful micro-dissection of the SCZ region was performed using a fine needle. To generate the neurosphere from the SCZ, micro-dissected SCZ tissue chunks were dissociated into single cells and then cultured as a suspension in the presence of epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF). After SCZ-aNSCs form neurospheres, they also can be maintained as neurospheres or monolayers for expansion. This procedure also demonstrates immunostaining processes with various markers for the detection of NSCs and their progeny after their expansion and differentiation in a monolayer culture. Here, a visual protocol of the SCZ-aNSC culture system is presented. This protocol contains detailed instructions for the micro-dissection of the SCZ region and for the maintenance and passaging of the cells.

<table><tbody><tr><td>&lt;strong&gt;Medium components&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>DMEM/F12&amp;nbsp;</td><td>Gibco</td><td>11320-033</td><td>+L-glutamin, +Sodium bicarbonate</td></tr><tr><td>Pen/Strep</td><td>Invitrogen</td><td>15140-122</td><td></td></tr><tr><td>N2 supplement</td><td>Gibco</td><td>17502-048</td><td></td></tr><tr><td>B27 supplement</td><td>Gibco</td><td>17504-044</td><td></td></tr><tr><td>&lt;strong&gt;Growth factor&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>bFGF</td><td>R&amp;amp;D</td><td>233-FB</td><td></td></tr><tr><td>EGF</td><td>Gibco</td><td>PHG0313</td><td></td></tr><tr><td>&lt;strong&gt;Buffer&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>PBS (10x)</td><td>BIOSOLUTION</td><td>BP007a</td><td>1x dilution</td></tr><tr><td>HBSS</td><td>Gibco</td><td>14175-095</td><td></td></tr><tr><td>&lt;strong&gt;Dissociattion buffer&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>Dispase II</td><td>Roche</td><td>04-942-078-001</td><td></td></tr><tr><td>Papain</td><td>Worthington</td><td>3126</td><td></td></tr><tr><td>Accutase</td><td>ICT</td><td>AT-104</td><td></td></tr><tr><td>&lt;strong&gt;Tool&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>Fine forceps</td><td>WPI</td><td>555229F</td><td></td></tr><tr><td>Scissors</td><td>Storz</td><td>E3321-C</td><td></td></tr><tr><td>Brain matrix (1 mm)</td><td>RWD</td><td>68707</td><td></td></tr><tr><td>Double-edged razor</td><td>DORCO</td><td>ST-300</td><td></td></tr><tr><td>30 G needle</td><td>SUNGSHIM</td><td>N1300</td><td></td></tr><tr><td>&lt;strong&gt;Materials&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>15 ml tubes</td><td>SPL</td><td>50015</td><td></td></tr><tr><td>50 ml tubes</td><td>SPL</td><td>50050</td><td></td></tr><tr><td>35 mm dish</td><td>SPL</td><td>10035</td><td>Petri dish</td></tr><tr><td>100 mm dish</td><td>SPL</td><td>10090</td><td>Petri dish</td></tr><tr><td>Cover slip (18 mm)</td><td>Deckglaser</td><td>111580</td><td></td></tr><tr><td>12 well dish</td><td>SPL</td><td>32012</td><td>non-coating</td></tr><tr><td>6 well dish</td><td>SPL</td><td>32006</td><td>non-coating</td></tr><tr><td>&lt;strong&gt;Coating materials&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>PLO</td><td>Sigma</td><td>P4957</td><td>0.01%</td></tr><tr><td>Laminin</td><td>Gibco</td><td>23017-015</td><td>10 mg/ml</td></tr><tr><td>&lt;strong&gt;Primary antibodies&amp;nbsp;&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>Nestin</td><td>Millipore</td><td>MAB353</td><td>mouse (1:1,000)</td></tr><tr><td>EGFR</td><td>Abcam</td><td>ab2430</td><td>rabbit (1:1,000)</td></tr><tr><td>DCX</td><td>Santa Cruz</td><td>SC8066</td><td>goat (1:500)</td></tr><tr><td>Tuj1</td><td>Sigma</td><td>T2200</td><td>rabbit (1:2,000)</td></tr><tr><td>GFAP</td><td>Invitrogen</td><td>13-0300</td><td>rat (1:1,000)</td></tr><tr><td>O4</td><td>Millipore</td><td>MAB345</td><td>mouse (1:500)</td></tr><tr><td>BrdU</td><td>Abcam</td><td>ab6326</td><td>Rat (1:500)</td></tr><tr><td>&lt;strong&gt;Secondary antibodies&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>anti-mouse 488</td><td>Invitrogen</td><td>A21202</td><td>1:500</td></tr><tr><td>anti-mouse cy3</td><td>Jackson</td><td>715-165-151</td><td></td></tr><tr><td>anti-mouse 647</td><td>Jackson</td><td>715-606-150</td><td></td></tr><tr><td>anti-rabbit 488</td><td>Alexa</td><td>A21206</td><td></td></tr><tr><td>anti-rabbit cy3</td><td>Jackson</td><td>711-165-152</td><td></td></tr><tr><td>anti-rabbit 647</td><td>Jackson</td><td>711-605-152</td><td></td></tr><tr><td>anti-goat 488</td><td>Alexa</td><td>A11055</td><td></td></tr><tr><td>anti-goat cy3</td><td>Jackson</td><td>705-165-147</td><td></td></tr><tr><td>anti-goat 647</td><td>Invitrogen</td><td>A21447</td><td></td></tr><tr><td>anti-rat 488</td><td>Invitrogen</td><td>A21208</td><td></td></tr><tr><td>anti-rat cy3</td><td>Jackson</td><td>712-166-150</td><td></td></tr><tr><td>anti-rat 647</td><td>Jackson</td><td>712-605-153</td><td></td></tr><tr><td>&lt;strong&gt;Immunostaining materials&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>BSA</td><td>Millipore</td><td>82-100-6</td><td>3% BSA with 0.1% Triton X-100 in PBS</td></tr><tr><td>Triton X-100</td><td>usb</td><td>22686</td><td></td></tr><tr><td>4% PFA</td><td>Biosesang</td><td>P2031</td><td></td></tr><tr><td>Hoechest33342</td><td>Life Technology</td><td>H3570</td><td>Dye for staining nuclei</td></tr></tbody></table>

isolation and culture of adult neural stem cells from the mouse subcallosal zone

Adult neural stem cells (aNSCs) can be used for the regeneration of damaged brain tissue. NSCs have the potential for differentiation and proliferation into three types of cells: neurons, astrocytes, and oligodendrocytes. Identifying aNSC-derived regions and characterizing the aNSC properties are critical for the potential use of aNSCs and for the elucidation of their role in neural regeneration. The subcallosal zone (SCZ), located between white matter and the hippocampus, has recently been reported to contain aNSCs and continuously give rise to neuroblasts. A low percentage of aNSCs from the SCZ is differentiated into neurons; most cells are differentiated into glial cells, such as oligodendrocytes and astrocytes. These cells are suggested to have a therapeutic potential for traumatic cortical injury. This protocol describes in detail the process to generate SCZ-aNSCs from an adult mouse brain. A brain matrix with intervals of 1 mm is used to obtain the SCZ-containing coronal slices and to precisely dissect the SCZ from the whole brain. The SCZ sections are initially subjected to a neurosphere culture. A well-developed culture system allows for the verification of their characteristics and can increase research on NSCs. A neurosphere culture system provides a useful tool for determining proliferation and collecting the genuine NSCs. A monolayer culture is also an in vitro system to assay proliferation and differentiation. Significantly, this culture system provides a more homogenous environment for NSCs than the neurosphere culture system. Thus, using a discrete brain region, these culture systems will be helpful for expanding our knowledge about aNSCs and their applications for therapeutic uses.

Defining the culture system for aNSCs from the unknown neurogenic region is essential for understanding these cells and for developing their potential use in brain repair12. It is known that NSCs in different developmental stages or in different regions behave differently3,4. Recently, it was reported that SCZ-derived cells exhibit differential potentials for neuronal differentiation in vivo and in vitro compared to SVZ-derived cells7-9. ...

Watch this Scientific Journal Video about Isolation and Culture of Adult Neural Stem Cells from the Mouse Subcallosal Zone at JoVE.com

Isolation and Culture of Adult Neural Stem Cells from the Mouse Subcallosal Zone

Establishing culture systems for the expansion of adult neural stem cells (aNSCs) allows for the examination and application of aNSCs for therapy. The subcallosal zone (SCZ) has recently been recognized as a novel neuroblast-forming region in adult mice. Here, methods for the isolation, expansion, and differentiation of SCZ-aNSCs are described.

Adult neural stem cells (aNSCs) can be used for the regeneration of damaged brain tissue. NSCs have the potential for differentiation and proliferation ...

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Neuroscience

15.1K Views.  Korea University College of Medicine. Establishing culture systems for the expansion of adult neural stem cells (aNSCs) allows for the examination and application of aNSCs for therapy. The subcallosal zone (SCZ) has recently been recognized as a novel neuroblast-forming region in adult mice. Here, methods for the isolation, expansion, and differentiation of SCZ-aNSCs are described. 

Video: Isolation and Culture of Adult Neural Stem Cells from the Mouse Subcallosal Zone

Isolation and Expansion of the Adult Mouse Neural Stem Cells Using the Neurosphere Assay

Isolation and expansion of the putative neural stem cells (NSCs) from the adult murine brain was first described by Reynolds and Weiss in 1992 employing a chemically defined serum-free culture system known as the neurosphere assay (NSA). In this assay, the majority of differentiated cell types die within a few days of culture but a small population of growth factor responsive precursor cells undergo active proliferation in the presence of epidermal growth factor (EGF) and/ basic fibroblastic growth factor (bFGF). These cells form colonies of undifferentiated cells called neurospheres, which in turn can be subcultured to expand the pool of neural stem cells. Moreover, the cells can be induced to differentiate, generating the three major cell types of the CNS i.e. neurons, astrocytes, and oligodendrocytes. This assay provides an invaluable tool to supply a consistent, renewable source of undifferentiated CNS precursors, which could be used for in vitro studies and also for therapeutic purposes.
This video demonstrates the NSA method to generate and expand NSCs from the adult mouse periventricular region, and provides technical insights to ensure one can achieve reproducible neurosphere cultures. The procedure includes harvesting the brain from the adult mouse, micro-dissection of the periventricular region, tissue preparation and culture in the NSA. The harvested tissue is first chemically digested using trypsin-EDTA and then mechanically dissociated in NSC medium to achieve a single cell suspension and finally plated in the NSA. After 7-10 days in culture, the resulting primary neurospheres are ready for subculture to reach the amount of cells required for future experiments.

This video protocol demonstrates the neurosphere assay method to generate and expand neural stem cells from the adult mouse periventricular region, and provides technical insights to ensure one can achieve reproducible neurosphere cultures.

Isolation and expansion of the putative neural stem cells (NSCs) from the adult murine brain was first described by Reynolds and Weiss in 1992 employing a ...

Establishing Embryonic Mouse Neural Stem Cell Culture Using the Neurosphere Assay

In mammalians, stem cells acts as a source of undifferentiated cells to maintain cell genesis and renewal in different tissues and organs during the life span of the animal. They can potentially replace cells that are lost in the aging process or in the process of injury and disease. The existence of neural stem cells (NSCs) was first described by Reynolds and Weiss (1992) in the adult mammalian central nervous system (CNS) using a novel serum&#8208;free culture system, the neurosphere assay (NSA). Using this assay, it is also feasible to isolate and expand NSCs from different regions of the embryonic CNS. These in vitro expanded NSCs are multipotent and can give rise to the three major cell types of the CNS. While the NSA seems relatively simple to perform, attention to the procedures demonstrated here is required in order to achieve reliable and consistent results. This video practically demonstrates NSA to generate and expand NSCs from embryonic day 14-mouse brain tissue and provides technical details so one can achieve reproducible neurosphere cultures. The procedure includes harvesting E14 mouse embryos, brain microdissection to harvest the ganglionic eminences, dissociation of the harvested tissue in NSC medium to gain a single cell suspension, and finally plating cells in NSA culture. After 5-7 days in culture, the resulting primary neurospheres are passaged to further expand the number of the NSCs for future experiments.

This video protocol demonstrates the application of the neurosphere assay for the isolation and expansion of neural stem cells from the ganglionic eminences of embryonic day 14-mouse brain.

In mammalians, stem cells acts as a source of undifferentiated cells to maintain cell genesis and renewal in different tissues and organs during the life ...

Isolation and Culture of Neural Crest Stem Cells from Human Hair Follicles

Hair follicles undergo lifelong growth and hair cycle is a well-controlled process involving stem cell proliferation and quiescence. Hair bulge is a well-characterized niche for adult stem cells1. This segment of the outer root sheath contains a number of different types of stem cells, including epithelial stem cells2, melanocyte stem cells3 and neural crest like stem cells4-7. Hair follicles represent an accessible and rich source for different types of human stem cells. We and others have isolated neural crest stem cells (NCSCs) from human fetal and adult hair follicles4,5. These human stem cells are label-retaining cells and are capable of self-renewal through asymmetric cell division in vitro. They express immature neural crest cell markers but not differentiation markers. Our expression profiling study showed that they share a similar gene expression pattern with murine skin immature neural crest cells. They exhibit clonal multipotency that can give rise to myogenic, melanocytic, and neuronal cell lineages after in vitro clonal single cell culture. Differentiated cells not only acquire lineage-specific markers but also demonstrate appropriate functions in ex vivo conditions. In addition, these NCSCs show differentiation potential toward mesenchymal lineages. Differentiated neuronal cells can persist in mouse brain and retain neuronal differentiation markers. It has been shown that hair follicle derived NCSCs can help nerve regrowth, and they improve motor function in mice transplanted with these stem cells following transecting spinal cord injury8. Furthermore, peripheral nerves have been repaired with stem cell grafts9, and implantation of skin-derived precursor cells adjacent to crushed sciatic nerves has resulted in remyelination10. Therefore, the hair follicle/skin derived NCSCs have already shown promising results for regenerative therapy in preclinical models.
Somatic cell reprogramming to induced pluripotent stem (iPS) cells has shown enormous potential for regenerative medicine. However, there are still many issues with iPS cells, particularly the long term effect of oncogene/virus integration and potential tumorigenicity of pluripotent stem cells have not been adequately addressed. There are still many hurdles to be overcome before iPS cells can be used for regenerative medicine. Whereas the adult stem cells are known to be safe and they have been used clinically for many years, such as bone marrow transplant. Many patients have already benefited from the treatment. Autologous adult stem cells are still preferred cells for transplantation. Therefore, the readily accessible and expandable adult stem cells in human skin/hair follicles are a valuable source for regenerative medicine.

This article presents a robust protocol for isolation and culture of neural crest stem cells from human hair follicles.

Hair follicles undergo lifelong growth and hair cycle is a well-controlled process involving stem cell proliferation and quiescence. Hair bulge is a ...

Isolation and Culture of Rat Embryonic Neural Cells: A Quick Protocol

We are describing a quick method to dissociate and culture hippocampal or cortical neurons from E15-17 rat embryos. The procedure can be applied successfully to the isolation of mouse and human primary neurons and neural progenitors. Dissociated neurons are maintained in serum-free medium up to several weeks. These cultures can be used for nucleofection, immunocytochemistry, nucleic acids preparation, as well as electrophysiology. Older neuronal cultures can also be transfected with a good efficiency rate by lentiviral transduction and, less efficiently, with calcium phosphate or lipid-based methods such as lipofectamine.

We describe a rapid methodology to isolate and culture hippocampal and cortical neurons from rodent embryos. This protocol allows us to perform experiments in which nearly pure neuronal cultures are required.

We are describing a quick method to dissociate and culture hippocampal or cortical neurons from E15-17 rat embryos. The procedure can be applied ...

Growing Neural Stem Cells from Conventional and Nonconventional Regions of the Adult Rodent Brain

Recent work demonstrates that central nervous system (CNS) regeneration and tumorigenesis involves populations of stem cells (SCs) resident within the adult brain. However, the mechanisms these normally quiescent cells employ to ensure proper functioning of neural networks, as well as their role in recovery from injury and mitigation of neurodegenerative processes are little understood. These cells reside in regions referred to as &#34;niches&#34; that provide a sustaining environment involving modulatory signals from both the vascular and immune systems. The isolation, maintenance, and differentiation of CNS SCs under defined culture conditions which exclude unknown factors, makes them accessible to treatment by pharmacological or genetic means, thus providing insight into their in vivo behavior. Here we offer detailed information on the methods for generating cultures of CNS SCs from distinct regions of the adult brain and approaches to assess their differentiation potential into neurons, astrocytes, and oligodendrocytes in vitro. This technique yields a homogeneous cell population as a monolayer culture that can be visualized to study individual SCs and their progeny. Furthermore, it can be applied across different animal model systems and clinical samples, being used previously to predict regenerative responses in the damaged adult nervous system.

Neural stem cells harvested from the adult brain are increasing utilized in applications ranging from the basic research of nervous system development to exploring potential clinical applications in regenerative medicine. This makes rigorous control in the isolation and culturing conditions used to grow these cells critical to sound experimental outcomes.

Recent work demonstrates that central nervous system (CNS) regeneration and tumorigenesis involves populations of stem cells (SCs) resident within the ...

One Mouse, Two Cultures: Isolation and Culture of Adult Neural Stem Cells from the Two Neurogenic Zones of Individual Mice

The neurosphere assay and the adherent monolayer culture system are valuable tools to determine the potential (proliferation or differentiation) of adult neural stem cells in vitro. These assays can be used to compare the precursor potential of cells isolated from genetically different or differentially treated animals&#160;to determine the effects of exogenous factors on neural precursor cell proliferation and differentiation and to generate neural precursor cell lines that can be assayed over continuous passages. The neurosphere assay is traditionally used for the post-hoc identification of stem cells, primarily due to the lack of definitive markers with which they can be isolated from primary tissue&#160;and has the major advantage of giving a quick estimate of precursor cell numbers in brain tissue derived from individual animals. Adherent monolayer cultures, in contrast, are not traditionally used to compare proliferation between individual animals, as each culture is generally initiated from the combined tissue of between 5-8 animals. However, they have the major advantage that, unlike neurospheres, they consist of a mostly homogeneous population of precursor cells and are useful for following the differentiation process in single cells. Here, we describe, in detail, the generation of neurosphere cultures and, for the first time, adherent cultures from individual animals. This has many important implications including paired analysis of proliferation and/or differentiation potential in both the subventricular zone (SVZ) and dentate gyrus (DG) of treated or genetically different mouse lines, as well as a significant reduction in animal usage.

Here we describe a detailed protocol for the simultaneous generation of neural precursor cell cultures, as either adherent monolayers or neurospheres, from the subventricular zone and dentate gyrus of individual adult mice.

The neurosphere assay and the adherent monolayer culture system are valuable tools to determine the potential (proliferation or differentiation) of adult ...

Isolation and Culture of Embryonic Mouse Neural Stem Cells

Neural stem cells (NSCs) are multipotent and can give rise to the three major cell types of the central nervous system (CNS). In vitro culture and expansion of NSCs provide a suitable source of cells for neuroscientists to study the function of neurons and glial cells along with their interactions. There are several reported techniques for the isolation of neural stem cells from adult or embryo mammalian brains. During the microsurgical operation to isolate NSCs from different regions of the embryonic CNS, it is very important to reduce the damage to the brain cells to obtain the highest ratio of live and expandable stem cells. A possible technique for stress reduction during isolation of these cells from the mouse embryo brain is the reduction of surgical time. Here, we demonstrate a developed technique for rapid isolation of these cells from the E13 mouse embryo ganglionic eminence. Surgical procedures include harvesting E13 mouse embryos from the uterus, cutting the frontal fontanelle of the embryo with a bent needle tip, extracting the brain from the skull, microdissection of the isolated brain to harvest the ganglionic eminence, dissociation of the harvested tissue in NSC medium to gain a single cell suspension, and finally plating cells in suspension culture to generate neurospheres.

Here, we introduce a novel microsurgical technique for the isolation of neural stem cells from the E13 mouse embryo ganglionic eminence.

Neural stem cells (NSCs) are multipotent and can give rise to the three major cell types of the central nervous system (CNS). In vitro culture and ...

Efficient Nucleofection of NSCs Isolated from the Murine Subventricular Zone

Isolation, Expansion, and Nucleofection of Neural Stem Cells from Adult Murine Subventricular Zone

Isolation and expansion of neural stem cells (NSCs) from the subventricular zone (SVZ) of the adult mouse brain can be achieved in a medium supplemented with basic fibroblast growth factor (bFGF) and epidermal growth factor (EGF) as mitogens, producing clonal aggregates known as neurospheres. This in vitro system is a valuable tool for studying NSC potential. Transfection of siRNAs or genes carried in plasmids can be used to induce perturbations to gene expression and study NSC biology. However, the exogenous nucleic acid delivery to NSC cultures is challenging due to the low efficiency of central nervous system (CNS) cells transfection. Here, we present an improved nucleofection system that achieves high efficiency of gene delivery in expanded NSCs from adult murine SVZ. We demonstrate that this relatively simple method enhances gene perturbation in adult NSCs, surpassing traditional transfection protocols with survival rates exceeding 80%. Moreover, this method can also be applied in primary isolated NSCs, providing a crucial advancement in gene function studies through gene expression manipulation via knockdown or overexpression in neurosphere cultures.

Author Spotlight: Improved Nucleofection for High-Efficiency Gene Delivery in Murine Subventricular Zone-Derived Neural Stem Cell Cultures

Here, we describe a nucleofection system designed to enhance gene delivery efficiency in expanded neural stem cells (NSCs) isolated from the adult murine subventricular zone. The findings demonstrate that this method significantly improves gene perturbation in NSCs, surpassing the effectiveness of traditional transfection protocols and enhancing cell survival rate.

Isolation and expansion of neural stem cells (NSCs) from the subventricular zone (SVZ) of the adult mouse brain can be achieved in a medium supplemented ...

Isolation and Culturing of Adult Neural Stem Cells from the Mouse Subcallosal Zone

Source: Kim, J. Y., et al. <a href="https://app.jove.com/v/54929">Isolation and culture of adult neural stem cells from the mouse subcallosal zone.</a> J. Vis. Exp. (2016)
The video demonstrates the process of isolating and culturing neural stem cells from the mouse brain&#39;s subcallosal zone. It involves dissecting tissue, enzymatic dissociation, and culturing them with differentiation factors to develop into mature neural cells.

Izolacja i hodowla dorosłych nerwowych komórek macierzystych ze strefy podmodzelowej myszy

1. Preparation of Materials and Culture Medium

	For the dissection and dissociation of the SCZ (Subcallosal zone), wrap the brain matrix, double-edged ...

JoVE Encyclopedia of Experiments

Neuronal Culture Techniques

Primary Neuronal Culture

Obtaining a Mixed Oligodendrocyte and Astrocyte Culture From Adult Mouse Neural Stem Cells

For neural stem cell isolation from the subventricular zone from 2.5-month-old adult mice, place brains from four to five adult mice into a 50-milliliter tube of ice-cold HBSS and place one brain ventral side down in the rostrocaudal direction on a sterile aluminum foil-covered flask filled with -20 degrees Celsius overnight cold water. Use a razor blade to remove the olfactory bulbs, and to cut two to three one-millimeter thick coronal slices from the cortex to the optical chiasma. Place the slices on the cold surface in a ventro-dorsal position, and identify the corpus callosum and the two lateral ventricles. Using magnification, isolate the walls of the lateral ventricles, taking care not to include pieces of the corpus callosum, and place the isolated tissue in 5 to 10 milliliters of enzymatic dissociation buffer for a 15-minute incubation at 37 degrees Celsius.
At the end of the incubation, pipette the tissues at least 50 times before incubating the samples at 37 degrees Celsius for an additional 10 minutes. At the end of the incubation, neutralize the trypsin with 5 milliliters of standard culture medium and filter the tissue suspension through a 70-micron filter. Centrifuge the filtered solution for five minutes at 400 times g and resuspend the pellet in sucrose solution for a second centrifugation. At the end of the centrifugation, resuspend the pellet in bovine serum albumin washing solution for another centrifugation, then resuspend the pellet in standard culture medium for counting and plate the cells in an upright T25 or T45 flask.
For primary neurosphere differentiation, add basic fibroblast and endothelial growth factors to the neural stem cell culture every two days. When the neurospheres reach a 100 to 500-micron diameter, passage the cells by mechanical dissociation according to standard protocols.
For oligosphere differentiation, treat the cells with basic fibroblast growth factor and platelet-derived factor AA every two days. When the oligospheres reach a 100 to 150-micron diameter, dissociate the spheres by mechanical dissociation according to standard protocols, and seed the cell suspension at a 3,000 cell per square centimeter density onto Poly-D/L-Ornithine laminin coated plates. After three days, replace the supernatant of each culture with the same volume of oligodendrocyte differentiation medium.