In the modern age of drug development, 3D cell culture models have come to prominence as a promising alternative to traditional methods, such as 2D cell culture and animal testing. Yet, amidst this scientific revolution, one must pause and ponder: What real relevance do these models have, especially in the field of neuroscience? Imagine the challenges faced in developing drugs for neurodegenerative diseases like Alzheimer’s or Parkinson’s. The stakes are high, and the need for innovative solutions is more pressing than ever. Having a model that is powerfully predictive while still cost-effective and animal-free is a game changer; but only if it works. Here, we discuss how 3D cell culture models are useful predictors of potential drug activity and how they can improve the success of your drug development pipeline.

In traditional preclinical drug development, monolayer cell culture and animal studies play a crucial role in characterizing a drug’s potency, efficacy, and safety. The emergence of 3D cell culture sparked optimism that it could revolutionize this testing paradigm. The unique configuration of cells in a 3D sphere was anticipated to offer a viable alternative, capturing physiologically relevant features of the in vivo environment. This includes the production of extracellular matrix, preservation of native cell morphologies, and the establishment of diffusion gradients for molecules like oxygen and other nutrients. The promise lies in the ability of 3D cell culture to replicate these critical elements, possibly reducing or even replacing animal studies. In recent years, many researchers have been able to demonstrate the practical relevance of 3D cell culture in preclinical research for various cell and tissue types. Notably, in 2013, M. Lancaster’s lab demonstrated the first application of 3D cell culture to neural cells, showcasing the ability for the spheres to be induced to a disease-state (microcephaly, in this case)[1]. Since then, researchers have been using neural spheres to unlock new knowledge about brain development and physiology.

One approach to measuring the functional output of neurons has lent a hand to 3D neural models and helped them become a viable option for preclinical drug development studies: the calcium imaging assay. In neurons and other signaling cell types, a burst of calcium occurs when a cell fires an electrical signal; this can be used to monitor and characterize electrical signaling waves from groups of neurons using a fluorescent probe specific for calcium. In 3D spheres, this output allows researchers to collect data about the functional activity of the culture without having to adapt monolayer-based assays for use with spheres. This finding has sparked innovative investigations into how Ca2+ imaging can be used as a practical means for early-stage drug characterization using 3D neural spheres. These studies have shown that functional assessment of 3D neural spheres is useful and can be applied to high-throughput screening [2]. Intriguingly, these studies also demonstrate that 3D spheres have a more consistent response to known neuromodulating molecules (such as TTX and 4AP) compared to 2D cultures using the same cell source [3].

Overall, 3D neural cell cultures have the power to respond to developmental drugs in ways that can be expected in the in vivo system. From successful implementation in the study of brain development and basic physiology, these models have made the leap to industrial applications with the expectation that they can improve success rates of drugs that make it to the clinical trial stage of development. Investigators have been able to show that these models are a viable option for developing a neurologically effective drug for use in humans. Here at Biotect Services, we offer cutting edge 3D neural cell culture using proven protocols to design studies that can help our clients discover critical insights about their neuroscience drug products. From basic viability studies to high-content fluorescent analysis, Biotect Services has the expertise and resources to use 3D neural spheres to enable early-stage drug developers to make leaps toward their clinical development goals.

Written by: Katelynne Donnelly, M.S., January 2024

1.      Lancaster M.A.,Renner M.,Martin C.A.,et al. Cerebral organoids model human brain development and microcephaly. Nature. (2013).501(7467), 373-9. https://doi.org/10.1038/nature12517

2.      Boutin, M. E., Strong, C. E., Van Hese, B., Hu, X., Itkin, Z., Chen, Y. C., LaCroix, A., Gordon, R., Guicherit, O., Carromeu, C., Kundu, S., Lee, E., & Ferrer, M. (2022). A multiparametric calcium signal screening platform using iPSC-derived cortical neural spheroids. SLAS discovery : advancing life sciences R & D, 27(4), 209–218. https://doi.org/10.1016/j.slasd.2022.01.003

3.      Woodruff, G., Phillips, N., Carromeu, C., Guicherit, O., White, A., Johnson, M., Zanella, F., Anson, B., Lovenberg, T., Bonaventure, P., & Harrington, A. W. (2020). Screening for modulators of neural network activity in 3D human iPSC-derived cortical spheroids. PloS one, 15(10), e0240991. https://doi.org/10.1371/journal.pone.0240991