Co-Cultures and Tox Assays

Data End Points Differ
Our clients continue to use our cells and kits for co-culturing. The goal is to develop the most in vivo like results possible.

They find that single cell vs multi cell type co-cultures drive different data sets.

At each dose, the results vary and as the dose of Bis1 increases this variation increases.

We welcome your questions, input and feedback on our co-cultures. Pete Shuster, Owner, pshuster@neuromics.com or 612-801-1007.

Human alpha-Sensory Neurons

Put Them to Work!

We continue to add unique primary Human Neurons to our offerings.

We have discounted our new alpha-Sensory Neurons to make it easier to buy and try-only 850 USD/1,000,000 cells.

Just thaw and culture. Simply culture on ECM- Laminin or Fibronectin coatings with our alpha Motor Neuron Maintaining Media. Questions? Please contact me directly 612-801-1007 or pshuster@neuromics.com. Pete Shuster, CEO and Owner, Neuromics.

Apoptosis and Neurodegeneration

Towards the Development of Disease Specific Assays
Neurodegenerative diseases are becoming increasingly prevalent, especially in the Western societies, with larger percentage of members living to an older age. They have to be seen not only as a health problem, but since they are care-intensive, they also carry a significant economic burden.

Apoptotic pathways are induced in many of these diseases and are key culprits in disease progression.

Figure: Schematic representation of apoptotic pathways. Apoptosis triggered by internal (intrinsic) or external (extrinsic) stress signals that is activated by binding of ligands (e.g. FasL, APO-2L, TRAIL, TNF) to cell surface receptors (e.g. Fas, DR4, DR5, TNF-R1). The intrinsic apoptosis pathway might be triggered by p53 upon DNA damage following exposure to cellular stress. In the intrinsic pathway, death signal reaches mitochondria, leading to release of cytochrome c, which can binds to Apaf1. The cytochrome c/Apaf1 make a complex with pro-caspase-9 (in the presence of dATP), activates caspase-9, which promotes caspase-3 activation, eventually leading to cell death. The extrinsic pathway is initiated through the stimulation of the members of tumor necrosis factor receptor (TNF-R) family (transmembrane death receptors) by their respective ligands. These receptors activate pro-caspases-8, -10 by recruiting the endogenous adaptor protein FADD. Procaspase-8, -10 cleave themselves to form activated caspase-8 or -10. Ultimately, effector enzymes such as caspase-3, -6, -7 are activated in this cascade to mediate apoptosis. Likewise, there can be cross-talk between the intrinsic and extrinsic pathways. For example caspase-8 may cleave Bid to form tBid that is a strong activator of the intrinsic/mitochondrial apoptotic pathway. The intrinsic pathway is usually activated by the recruitment of BAX and BAK to outer mitochondrial membrane, causing cytochrome c release formation of apoptosome and subsequent activation of caspase-9. Activated caspase-9 proteolytically activates caspases-3, -6, and -7. Moreover, some of the effector caspases also can activate caspase-8, forming a positive amplification loop. doi:10.1016/j.pneurobio.2013.10.004.

Working with the Apoptosis Experts at Immunochemistry Technologies and Human Astroglial-Neuron Biosensors Experts at ArunA Biomedical, we plan on  developing disease specific assays. Here's a map of the general process.

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We welcome feedback and input on your interests. You can email rose@neuromics.com. We will continue to post updates on exciting new developments.

Neurite Outgrowth Assays

Cells, Media and Markers

I have previously posted use of our Neurons in Live Content Assays for the study of Neurite Outgrowth: Neurons-Live Content Assays. These assays are critical for the study of repair and regeneration.

A recent publication featured several of our Neuron Markers: Serena Quarta, Bastian E. Baeumer, Nadja Scherbakov1, Manfred Andratsch, Stefan Rose-John, Georg Dechant3, Christine E. Bandtlow, and Michaela Kress: Peripheral Nerve Regeneration and NGF-Dependent Neurite Outgrowth of Adult Sensory Neurons Converge on STAT3 Phosphorylation Downstream of Neuropoietic Cytokine Receptor gp130. The Journal of Neuroscience, 24 September 2014, 34(39): 13222-13233; doi: 10.1523/JNEUROSCI.1209-13.2014.
Live labeling of neuron cultures: After 20 or 48 h, neurons were live-labeled with α-gp130 antibody diluted in cold TNB medium for 30 min on ice. After washing, neurons were incubated with the secondary antibody diluted in cold TNB medium for 30 min and washed with PBS. Cells were fixed either with 4% PFA for 20 min at room temperature (RT) or with methanol at −20°C for 2 min. After permeabilization with 0.01% TX-100 (Pierce) unspecific binding was blocked for 30 min with 10% normal goat serum (Sigma-Aldrich) in PBS. Cells were incubated with the first antibody for 1 h, washed three times for 10 min with PBS and incubated with the appropriate secondary antibody for 30 min, counterstained with 4′, 6-diamidino-2-phenylindole (1:10,000; Sigma-Aldrich) and embedded in Mowiol (Calbiochem). As primary antibodies, α-gp130 (1:50; Neuromics), α-β-III-tubulin clone TuJ-1 (1:1000; R&D Systems), and α-neurofilament-H (α-NF-H; 1:200; Neuromics) were used. Secondary antibodies used were α-goat AlexaFluor 594 (1:1000; Invitrogen), chicken α-mouse AlexaFluor 594 or donkey α-mouse AlexaFluor 488 (1:1000; Invitrogen), and goat α-chicken AlexaFluor 568 (1:10,000; Invitrogen) for fluorescence microcopy.

Images: Reduced density of TuJ-1+ nerve endings in the epidermis in SNS-gp130−/− mice after lesion. A, Representative cross sections of hindpaw glabrous skin of naive and 12 dpl gp130fl/fl and SNS-gp130−/− mice stained with the pan neuronal marker TuJ-1. The dotted line indicates the border between dermis and epidermis. Scale bar, 40 μm. B, Quantification of the total number of TuJ-1+ fibers (NE) per 1000 μm2 of epidermal area shows a significant decrease in density in SNS-gp130−/− mice after lesion compared with control animals (*p < 0.05; n = 4 for each group). Data are presented as mean ± SEM and analyzed by Mann–Whitney U test. C, 3D reconstruction of the deeper layer of the dermis shows fewer nerve bundles in SNS-gp130−/− dermis compared with controls. D, No NF-H+ proprioceptive fibers were detectable in the epidermis of gp130fl/fl animals at 12 dpl. Scale bar, 40 μm.

If you want to learn more about our Neuron-Glial-Astrocyte based assay solutions do not hesitate to contact me (612-801-1007) or pshuster@neuromics.com. Pete Shuster, Owner and CEO, Neuromics.

Protocol for Flow Cytometric Sorting of Enriched Neuronal Cultures from iPSCs

Surface molecule profiles undergo dynamic changes in physiology and pathology, serve as markers of cellular state and phenotype and can be exploited for cell selection strategies and diagnostics. The isolation of well-defined cell subsets is needed for in vivo and in vitro applications in stem cell biology. In this technical report, the authors present an approach for defining a subset of interest in a mixed cell population by flow cytometric detection of intracellular antigens. They have developed a fully validated protocol that enables the co-detection of cluster of differentiation (CD) surface antigens on fixed, permeabilized neural cell populations defined by intracellular staining. Determining the degree of co-expression of surface marker candidates with intracellular target population markers (nestin, MAP2, doublecortin, TUJ1) on neuroblastoma cell lines (SH-SY5Y, BE(2)-M17) yielded a combinatorial CD49f^-/CD200^high surface marker panel. Its application in fluorescence-activated cell sorting (FACS) generated enriched neuronal cultures from differentiated cell suspensions derived from human induced pluripotent stem cells. Our data underlines the feasibility of using the described co-labeling protocol and co-expression analysis for quantitative assays in mammalian neurobiology and for screening approaches to identify much needed surface markers in stem cell biology: Turaç G, Hindley CJ, Thomas R, Davis JA, Deleidi M, et al. (2013) Combined Flow Cytometric Analysis of Surface and Intracellular Antigens Reveals Surface Molecule Markers of Human Neuropoiesis. PLoS ONE 8(6): e68519. doi:10.1371/journal.pone.0068519

Figure 1. Experimental outline. Schematic illustrating the research strategy of identifying novel surface marker combinations on a target population in neural and other stem cell differentiation systems for which intracellular, standard immunocytochemical markers are well established. Following harvesting, the resulting single cell suspension is subject to surface antigen candidate staining, followed by gentle fixation, permeabilization and subsequent co-staining with known intracellular markers. CD markers co-labeling the target population serve as positive markers, those absent on the target population serve as negative markers. In a separate, subsequent step, a combination of the identified positive and/or negative CD markers enables the flow cytometric enrichment of the viable population of interest from a heterogeneous cell suspension for further study and biomedical applications. doi:10.1371/journal.pone.0068519.g001.

Figure 2. Accurate detection of intracellular antigens with optimized fixation-permeabilization conditions preserving surface antigens. Flow cytometric detection of TUJ1, MAP2 and nestin antigens in BJ fibroblasts and the neural SH-SY5Y cell line (A). TUJ1 and nestin are present in both cell lines, while the mature neuronal marker MAP2 was only detected in SH-SY5Y cells (arrows). Note stable fluorescent levels of the negative population, indicating low background staining using this protocol. Representative experiment of three independent repeats shown. (B) Corresponding validation by immunofluorescence analysis. (C) Quantitation of TUJ1, MAP2 and nestin intracellular antigen detection (n=3). Error bars indicate standard deviation. (D) Response of TUJ1 and MAP2 intracellular antigen expression to 6 DIV of 10 µM retinoic acid (RA) treatment of SH-SY5Y cells. Note disappearance/reduction of subsets negative for these markers (upward shift, green arrows), as well as a shift toward CD184low expression with differentiation (blue arrows). doi:10.1371/journal.pone.0068519.g003.

Please note: In addition to the our Human Mouse Monoclonal Nestin Antibody used in the study, we have an extensive catalog of stem cell solutions. I will continue to post highlights of new applications.

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

Primary Hippocampal Neurons Performing!

I advertise our Primary Neurons and Astrocytes as being easy to culture, grow and maintain. We confirm this via the data/images our customers generously share and the many publications referencing use of the cells.

I would like to thank George Kenneth Todd (Patterson Lab at UC Davis) for these wonderful images of our e18 Primary Rat Hippocampal Neurons. These were taken at day 67!

Prior to staining, the cells were treated with Wnt5 for 2 min, then Wnt5 + Wnt3 for an additional 2 min during Calcium Imaging experiments. The cells were then fixed and stained for IP3R (green), Frizzled2 (blue), and B-Catenin (red), and the confocal images were captured at 10x. Notice the parallel neurites formation in image 3.


For staining culture options, check out our neuron-glial-astrocyte markers.