Rat Hippocampal Neurons

Used to Study Apoptosis Induced by Brain Insults
Although our primary human cells are increasingly being used in drug discovery and toxicology assays versus animal cells, we are always pleased to see the success of the latter in sophisticated studies.

This publication references use of our e18 rat hippocampal neurons. These cells continue to be easy to culture, pure and potent. Chiara Porro, Antonia Cianciulli, Teresa Trotta, Dario Domenico Lofrumento, Rosa Calvello and Maria Antonietta Panaro. (2019). Formyl-methionyl-leucyl-phenylalanine Induces Apoptosis in Murine Neurons: Evidence for NO-Dependent Caspase-9 Activation. Biology 8(1), 4; doi:10.3390/biology8010004.

Highlights
Formyl-methionyl-leucyl-phenylalanine (fMLP) may be present in the brain in the course of some infectious diseases of the central nervous system (CNS), although little is known about its role. This investigation was performed to study the effect of fMLP on neuron apoptosis. The results showed that fMLP treatment of primary cultures of neurons was able to induce morphological features of apoptosis in cell cultures, as well as activation of the intrinsic apoptotic pathway, through the upregulation of caspase-9 and caspase-3.

Figure. (A) Western blot analysis was performed on membrane-enriched cell extracts (25 µg lysate) of primary neurons. The blots were probed with formyl peptide receptor 2 (FPR2) antibody (Ab) and detected by chemiluminescence. A ~41 kDa band corresponding to FPR2 was observed as compared to the positive control. Lane 1: Marker; lane 2: Positive control, lane 3: Primary neuron lysate. (B) Immunofluorescence identification of FPR. Double staining shows the expression of the FPR receptor on the cell membrane and neurofilaments. FPR2 expression (green); skeleton protein staining of neuron-specific neurofilament 68 (red); DAPI nuclear staining (blue); cells stained by both neurofilament 68, FPR2 and DAPI (merged). Scale bar: 100 μm. 1): neurofilaments stain; 2) FPR2 expression; 3) DAPI stain; 4) merged.

The present study emphasizing the potential role of infectious agents, such as N-formyl peptides, in neurodegenerative diseases may help to promote the development of new therapies able to modulate the expression of the N-formyl peptide receptors.

Energize your Cell-Based Assays

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AlphaBioCoat Solution (AC001) is a biocompatible complex of extracellular matrix binding solution that is supplemented with growth factors. It helps accelerate cell attachment and cell growth. AC001 is the premium version of our Smooth Coat Solution (SC300).

It is ideal for plate coating due to its unique viscosity. Its coating greatly enables cell migration on cultured plate surfaces. Perfect for establishing primary cell lines, it can increase endothelial cell attachment, survival in culture, and cell growth. AlphaBioCoat Solution is great for both coating plates and T-flasks.

Interested? Please contact rose@neuromics.com.

Pure and Potent Human Primary Retinal Pigment Endothelial Cells (HRPES)

Culture Ready
Neuromics is a recognized leader in providing researchers 21-CFR Compliant Primary Human Cells.

Here we feature our new Retinal Pigment Epithelial Cell (HRPES). These hard to find cells are reasonably priced and culture ready,

HRPES in Culture

Cells are provided at passage 3. HRPEs growth medium (contains 10% serum and growth supplements, Alpha-33) is recommended for cell culture and these cells have a minimum average population doubling capacity of 8 when cultured following the detailed protocol.

Long Term Culturing of Cells

Non-Perfusion Model
Researchers, for some studies, are demanding the ability to maintain vibrant cultures for long periods of time.

Perfusion models afford this, but are expensive, sensitive and require specialized expertise. Given this, I believed it a good time to represent a protocol that can be used for our primary neurons and can be extrapolated to many of our other primary and stem cells.

Here's the complete protocol.

Rose Ludescher, Manager of Customer Satisfaction, is an expert in helping our customers successfully culturing cells. So if you need help with any of your cell-based assays do not hesitate to contact her. Just email your request to rose@neuromics.com.

eSC Derived hNP1 Neural Progenitors Astrocytic Differentiation

Protocol for Driving hNP1^TM Human Neural Progenitors to Astrocytes

There is a great demand for an easy way to generate human astrocytes in culture. I am pleased to present a protocol for differentiating our hNP1 Cells to Astrocytes. This comes from my friend Dr. Steve Stice and his team at ArunA Biomedical and University of Georgia: Majumder A, Dhara SK, Swetenburg R, Mithani M, Cao K, Medrzycki M, Fan Y, Stice SL. Inhibition of DNA methyltransferases and histone deacetylases induces astrocytic differentiation of neural progenitors. Stem Cell Res. 2013 Jul;11(1):574-86. doi: 10.1016/j.scr.2013.03.003. Epub 2013 Apr 2.

These enriched non-transformed human astrocyte progenitors will provide a critical cell source to further our understanding of how astrocytes play a pivotal role in neural function and development. Human neural progenitors derived from pluripotent embryonic stem cells and propagated in adherent serum-free cultures provide a fate restricted renewable source for quick production of neural cells; however, such cells are highly refractive to astrocytogenesis and show a strong neurogenic bias, similar to neural progenitors from the early embryonic central nervous system (CNS). We found that several astrocytic genes are hypermethylated in such progenitors potentially preventing generation of astrocytes and leading to the proneuronal fate of these progenitors. However, epigenetic modification by Azacytidine (Aza-C) and Trichostatin A (TSA), with concomitant signaling from BMP2 and LIF in neural progenitor cultures shifts this bias, leading to expression of astrocytic markers as early as 5days of differentiation, with near complete suppression of neuronal differentiation.

Images: Morphology and gene expression after 15 and 30 days of differentiation of cells with astrocytic treatment. Bright field images of hNP cells differentiated (A) with or (B) without astrocytic treatment. A and B compare morphology of cultured cells in treated vs. untreated differentiation at 15 days. Treated and untreated cells were cryopreserved at d6 and subsequently thawed and cultured for an additional 9 days. Flow cytometry analysis to determine percent of GFAP+ and S100B+ cells at d15 of differentiation. Data is presented as histograms for (C) GFAP and (D) S100B with corresponding immunoreactive cells in insets from a parallel culture. Immunocytochemistry detects expression of (E) GFAP with S100B (inset showing distinct staining for both markers), (F) GFAP with GLAST, and (G) GFAP with ALDH1L1 at d30 of differentiation.

The Protocol:  For astrocytic differentiation of hNP cells, neuronal differentiation media were supplemented with BMP2 (20 ng/mL) and combinations of Aza-C and TSA; Aza-C (500 nM), TSA (100 nM) and BMP2 (20 ng/mL) for 2 days, with one complete media change in between, followed by differentiation media supplemented with BMP2 but not with Aza-C or TSA. Cells were harvested prior to analysis at 5, 15 or 30 days of treatment or for cryopreservation at d6 or d10 of differentiation. For cryopreservation, cells were dissociated with Accutase™ and frozen in differentiation media containing10% DMSO. Viability was assessed at 30 days in Aza-C and TSA treated cultures by trypan blue exclusion, and datawas acquired using a Cellometer Auto T4® (Nexcelom Biosciences).

I will keep you updated on new differentiation protocols for our potent, pure and widely used hNP1 Human Neural Progenitors to new phenotypes.

Neuron-Glial Cultures-Setting a Higher Bar!

Improved Methods for Long Term, High Denisty Cultures

 

Dr. Randen Patterson and his team at UC Davis have developed new culturing techniques using our e18 Rat Primary Hippocampal Neurons. They have developed a protocol that allows for culturing of E18 hippocampal neurons at high densities for more than 120 days. These cultured hippocampal neurons are (i) well differentiated with high numbers of synapses, (ii) anchored securely to their substrate, (iii) have high levels of functional connectivity, and (iv) form dense multi-layered cellular networks. We propose that our culture methodology is likely to be effective for multiple neuronal subtypes–particularly those that can be grown in Neurobasal/B27 media. This methodology presents new avenues for long-term functional studies in neurons. This is good news indeed: Todd GK, Boosalis CA, Burzycki AA, Steinman MQ, Hester LD, et al. (2013) Towards Neuronal Organoids: A Method for Long-Term Culturing of High-Density Hippocampal Neurons. PLoS ONE 8(4): e58996. doi:10.1371/journal.pone.0058996.

 

Protocol Highlights: 
Substrate Preparation
1. On the day of plating, prepare 25 mm coverslips by removing them from 70% ethanol storage solution and propping them up at an angle in each well of a 6-well culture plate to allow drying. [No more than 5 plates (30 coverslips) should be dried simultaneously for 15–25 minutes in culture hood to avoid over-drying.]
2. Once dry, shake slips down flat into their respective wells and coat with 1 mL 0.1% poly-D-lysine, taking care to form a liquid meniscus on each slip. Carefully transfer coverslips into incubator, taking care to preserve meniscus.
3. Incubate for 1 hr at 37°C. [Keeping poly-D-lysine meniscus on top of coverslip is important; this serves to avoid poly-D-lysine coating under coverslip surface that may lead to problematic flotation of coverslip.] After incubation, remove poly-D-lysine and rinse each coverslip three times with 2 mL sterile deionized water. Take care to ensure coverslips do not completely dry at any point during the rinse. After the third and final rinse, leave coverslips in 2 mL sterile deionized water for at least 1 hr. Remove water just before plating, again, make sure to avoid over-drying. [This critical step requires attention. Take care to aspirate off all sterile water remaining from the final rinse, but also use caution as not to over-dry the coverslips. Ultimately, the coverslip must be mostly dry as to allow for the meniscus formation during plating (Fig. 1, Step 12), whereas over-drying can result in the neurons peeling off the glass coverslips days to weeks after plating.]

Fig 1: Neuron-Glial Culturing Steps
Preparation of Isolated Neurons (Numbers in Fig. 1 correspond to numbers below).
1. Store tissue at 4°C until ready to use. If dissecting your own cultures, upon isolation of the tissue, store in an appropriate storage media.
2. When ready to plate, make 2 mL of enzymatic solution without B27. In our case, we used Hibernate E-Ca, containing 4 mg (2 mg/mL) of papain. If making your own solution, use a commercially available papain dissociation kit. Make sure to sterile filter solution with 0.2 micron filter after adding papain if source of enzyme is not sterile.
3. Remove the storage media from the dissected tissue and transfer into sterile 15 mL screw-cap tube; be careful not to disturb or remove tissue from original tube. Save the storage media, do not discard.
4. Add 2 mL of media made in Step 2 to tissue (in our case, Hibernate E-Ca containing 2 mg/mL of papain). Incubate for 35 min at 37°C. [Be sure to add Hibernate E-Ca containing papain slowly as to avoid disturbing tissue.]
5. Remove enzymatic solution from tissue, again, take care not to disturb or remove tissue. Add back 1 mL of storage media saved in 15 mL tube.
6. Using a 1 mL pipettor with a sterile plastic pipette tip (tissue can adhere to glass pipettes), aspirate the tissue with the medium into the pipette and immediately dispense contents back into same container. Take care not to create bubbles. [This is another critical step that requires attention. Take care to make sure pipette tip remains in a stable position (as shown in Fig. 1, Step 6). Maintain slow, steady speed when both drawing in and re-dispensing media containing tissue.]
7. Repeat this trituration step 10–12 times or until most all the tissue is dissociated and the cells are dispersed. [Under close examination cell dispersion is highly visible. Stop pipetting immediately upon cell dispersion.]
8. Slowly transfer contents of the tissue tube into a new sterile 15 mL screw-cap tube.
9. Use the remainder of storage medium saved in Step 3 and rinse the interior of the tissue tube before adding it to the sterile 15 mL screw cap tube containing dispersed cells from step 7. [This step helps ensure minimal wastage, as any remaining cells should be saved with this extra rinse.]
10. Spin dispersed cells at 1,100 rpm (200Xg) for 1 min.
11. Discard the supernatant while being careful not to remove any of the cells from cell pellet.
12. Flick tube a few times to loosen the cell pellet. Re-suspend pellet in 2.4 mL of pre-warmed B27/Neurobasal/0.5 mM glutamine medium. Re-suspend by gently pipetting up and down. For E18 Hippocampus, medium includes 25 µM glutamate.
13. Plate cells within a meniscus (approx. 10 mm diameter) at a minimum of 40 µL per 25 mm coverslip. Take care not to disturb meniscus. [Periodically pipette up and down throughout plating process (no more than once every plate per 6 coverslips) to help maintain equal cell density. Again, plating with meniscus formation is critical.]
14. Incubate plated cells at 37°C with 5% CO2 and/or 9% or 20% oxygen for 1 hr.
15. Add 1.5 mL per well of pre-warmed 1:1 ACM/NbActiv4. [Slow and steady media addition rate and proper pipette position are necessary for successful plating density consistency. Position pipette tip at 45° angle along middle of 6-well interior sidewalls, dispense 1.5 mL as slowly and steadily as possible (see Steps 1–14).]
16. Incubate cells at 37°C with 5% CO2 and/or 9% or 20% oxygen.
17. Add Cytosine β-D-arabinofuranoside (Ara-C) to a final concentration of 5 µM, 5–6 days after plating to curb glial proliferation. [Remove 1/3 of media from each well and replace with equal volume containing final concentration of Ara-C]
18. After 4 days or longer, neurons are well differentiated. If further culture is desired, change 1/3 of medium with fresh, pre-warmed 1:1 ACM/NbActiv4 every 7–8 days.

Images: 40X Confocal Images of 30 DIV Hippocampal Cultures. Immunofluorescence detection of MAP-2 (green) and GFAP (red) in 30 DIV (A–C) cultured E18 hippocampal cells using a 40X objective. These images (A and B) clearly depict the intimate physical contact between glia processes and dendritic arbors. Under closer examination (CI and CII), it is clear that the dendrites have grown both bellow (blue arrows) and above (white arrows) glial processes, forming a highly interconnected three-dimensional network by 30 DIV. doi:10.1371/journal.pone.0058996.g004.
All Primary Neuron Assay Customer Publications

 

Related Content:

• Primary Neurons and Astrocytes-Primary human, rat and mouse neurons and glia/astrocytes.
• Neuronal-Glial Markers-Astrocytes, Glia, Microglia, Olidogodendrocytes, Progenitors and Schwann Cell Markers
• Cells, Cell Culturing Systems and Cell Based Assay Reagents-Cells, Petaka Cell Culturing Systems, Biolumonics Kits, Media, 3-D Scaffolds and Related Reagents Designed to Optimize Cell Based Assays

If you have any questions on optimizing your cell cultures, do not hesitate to contact me @ pshuster@neuromics.com or 612-801-1007