Cerebral Cortical Neurons Differentiation Service

Introduction of Cerebral Cortical Neurons

Classification, Function, and Location of Cortical Neurons

There are two broad classes of cortical neurons: interneurons, which make local connections; and projection neurons, which extend axons to distant intracortical, subcortical, and subcerebral targets. Projection neurons are glutamatergic neurons characterized by a typical pyramidal morphology that transmit information between different regions of the neocortex and to other regions of the brain. During development, they are generated from progenitors of the neocortical germinal zone located in the dorsolateral wall of the telencephalon. By contrast, GABA (γ-aminobutyric acid)-containing interneurons and Cajal Retzius cells are generated primarily from progenitors in the ventral telencephalon and cortical hem, respectively, and migrate long distances to their final locations within the neocortex. In this manner, multiple progenitor zones contribute to the rich variety of neuronal types found in the neocortex.

Major Subtypes of Projection Neuron within the Neocortex

Fig.1 Major subtypes of projection neurons within the neocortex.¹

Commissural

• Callosal projection neurons

Projection neurons of small to medium pyramidal size that are primarily located in layers II/III, V, and VI, and extend an axon across the corpus callosum (CC). At least three major types of callosal neurons can be classified. These maintain single projections to the contralateral cortex; dual projections to the contralateral cortex and ipsilateral or contralateral striatum; and dual projections to the contralateral cortex and ipsilateral frontal cortex. These never project axons to targets outside the telencephalon.

Corticofugal (subcortical)

• Corticothalamic neurons

Projection neurons primarily located in cortical layer VI, with a smaller population in layer V, that project subcortically to different nuclei of the thalamus (Th).

• Subcerebral projection neurons

Subcerebral projection neurons are also referred to as type I layer V projection neurons. These include pyramidal neurons of the largest size, which are located in deep-layer V and extend projections to the brainstem and spinal cord. They can be even further subdivided into several distinct projection neuron subtypes.

Among them:

• Corticotectal neurons are located in the visual area of the cortex and maintain primary projections to the superior colliculus, with secondary collateral projections to the rostral pons (Po).
• Corticopontine neurons maintain primary projections to the pons.
• Corticospinal motor neurons are located in the sensorimotor area of the cortex and maintain primary projections to the spinal cord, with secondary collaterals to the striatum, red nucleus, caudal pons, and medulla.

Many other subtypes of subcerebral projection neurons exist that send axons to different areas of the brainstem or have different combinations of collaterals but are not depicted here for simplicity.

Cerebral Cortical Neurons and Diseases

Understandably, a holistic appraisal of all steps of cortical development (e.g., proliferation, modes of cell division, cell differentiation, cell migration) is key to unraveling the pathophysiological mechanisms underlying cortical malformations such as microcephaly (small brain), lissencephaly (smooth brain), and heterotopia (abnormally positioned neurons), often associated with intractable epilepsy and intellectual disability. Genetic and environmental factors (e.g., viruses such as Zika) can perturb these critical steps. Elucidating the intrinsic and extrinsic mechanisms controlling progenitor cell proliferation versus (vs) neuronal differentiation will help shed light on cortical expansion, gyrification, and ultimately neocortical evolution.

Services at Creative Biolabs

Creative Biolabs has been focusing on neural differentiation models over years, thus we have accumulated extensive experience from practice. In addition, we have also optimized our platform with advanced facilities and technologies thus we are capable of providing quality-reliable cerebral cortical neurons differentiation model service. If you are interested in custom cerebral cortical neurons differentiation models, or you have any other questions about our services, please don't hesitate to contact us for more information.

Here's a brief overview of the differentiation service.

• Preparation of Pluripotent Stem Cells - This service begins with the procurement and preparation of high-quality pluripotent stem cells. These cells are ethically sourced and prepared in our fully equipped laboratories under strict safety regulations. Of course, our clients can also provide cell sources.
• Cell Differentiation - We differentiate pluripotent stem cells into neural progenitor cells using well-established, standard protocols.
• Maturation - We further differentiate the neural progenitor cells into cerebral cortical neurons. This process happens over a period of weeks and involves carefully timed steps and conditions to guide proper neuronal development and maturation.
• Quality Control - Every batch of developed cells is tested for purity, identity, functionality, and sterility. This rigorous quality control procedure ensures that the neurons exhibit the expected phenotypic and genetic characteristics, and are free from contamination.

Our professional teamwork involves multidisciplinary skills, encompassing cell biology, molecular biology, and biochemical engineering, allowing us to reliably generate cerebral cortical neurons. In addition, our company also offers customized services to accommodate individual client needs. Customizations can include specific alterations to the differentiation protocol, or more extensive manipulations like genetic modification of the stem cells prior to differentiation.

We also offer other related services, including but not limited to:

Published Data

K Autar. et al. presented a unique scheme for differentiating iPSC into cortical neurons and the maturation process for obtaining functionally mature cortical neuronal circuits. In their study, they developed a phenotypic model of hiPSC-derived cortical neurons, characterized their maturation process, and investigated its integration with applications of MEA for disease modeling.

As shown, they performed immunocytochemistry using cortical neuron markers to confirm cortical neuron identity. These neural markers were further quantified using flow cytometry. These analyses suggest that if sufficient maturation time is utilized, this differentiation protocol produces near-pure cortical neuronal cultures, thus enabling the study of neuron-only characteristics.

Fig. 2 Characterization of hiPSC-cortical neuron maturation via phase microscopy, immunocytochemistry, and flow cytometry.²

Applications

As a leading biotechnology company, we provide a state-of-the-art cerebral cortical neuron differentiation service that aims to advance research in neuronal function modeling, neurodegenerative diseases, drug discovery, and regenerative therapy.

• Neuronal Function Modeling - for studying neuronal maturation, synaptic functionality, axon guidance, neural plasticity, and comprising processes connected with learning, memory, and cognition.
• Neurodegenerative Diseases - for helping in exploring disease mechanisms, discovering biomarkers, and testing potential therapeutics.
• Drug Discovery - for accelerating testing of potential drug candidates against different targets in neurons. It allows high throughput screening of compound libraries for drug discovery and development.
• Toxicity Testing - for carrying out neurotoxicity testing of different compounds to assess their safety profile.

FAQs

• Q: Can you accommodate specific requests for the inclusion of additional cell types or co-culture systems in the differentiation process?
  A: Yes, we can incorporate additional cell types or establish co-culture systems as per the customer's requirements. Whether it involves astrocytes, microglia, or other supporting cells, we can tailor the differentiation process to facilitate complex in vitro models that better mimic the cellular interactions present in the brain.
• Q: What level of customization do you offer in terms of neuronal subtype specification, such as excitatory or inhibitory neurons, during the differentiation process?
  A: We offer a high degree of customization in specifying neuronal subtypes, including excitatory or inhibitory neurons, during the differentiation process. This can be achieved through precise modulation of signaling pathways, culture conditions, or genetic manipulation techniques tailored to the desired neuronal subtype.
• Q: What is the typical timeline for the entire process, from initiating the differentiation to obtaining functional cerebral cortical neurons?
  A: The timeline can vary depending on the complexity of the differentiation protocol and the specific requirements of your experiment. However, in general, our standard process typically takes between 4 to 6 weeks from the initiation of differentiation to the generation of functional cerebral cortical neurons ready for experimentation. We prioritize efficiency without compromising the quality of the final product.
• Q: What scale of experiments can this service accommodate? Can you provide differentiated neurons in large quantities if needed?
  A: Our service is scalable to accommodate a wide range of experimental needs. Whether you require a small batch of neurons for exploratory studies or large quantities for high-throughput screening or transplantation experiments, we have the capacity and expertise to meet your demands. We employ scalable culture systems and production processes to ensure consistent quality and quantity of differentiated neurons, regardless of the scale of your experiment.

Scientific Resources

Regulation and Drive of Neuronal Differentiation

References

1. Molyneaux, B. J., et al. Neuronal subtype specification in the cerebral cortex. Nat Rev Neurosci. 2007, 8(6): 427-37.
2. Autar, Kaveena, et al. "A functional hiPSC-cortical neuron differentiation and maturation model and its application to neurological disorders." Stem Cell Reports 17.1 (2022): 96-109.

For Research Use Only. Not For Clinical Use.