Three-dimensional (3D) cell culture, touted for exemplary physiological relevance, is an increasingly sought-after application to replace conventional tissue cultures that occur in two dimensions (2D).
The 2D cell culture model, in which cells grow as a monolayer adhered to a plastic surface, is the most commonly used method of growing cells
in vitro.
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2D cell cultures, particularly for mammalian cells, have served researchers well over the years due to several advantages.
Among these are inexpensive costs, low complexity procedures, easier maintenance, high proliferation rates, and standardized culture media.
Due to equal exposure to the culture medium, the cells also tend to exhibit homogenous cellular states, such as cell cycle stages.
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Many applications have also been established around 2D culture, such as routine cellular assays and high-throughput workflows.
Despite their utility, 2D cultures have significant limitations, which has led to the development of 3D cell culture models.
Advantages of 3D over 2D Culture
Cells in the body exist within a 3D environment, which directly influences complex interactions and signaling processes.
2D cultures will not accurately mimic natural conditions such as diverse phenotypes and morphologies of neighboring cells, cell polarization, variable access to oxygen and nutrients, and environmental niches.
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Experiments that rely on these conditions may lead to results that do not accurately represent
in vivo scenarios.
To overcome these limitations, a variety of 3D culture models have been developed, offering advantages such as more accurate
in vivo mimicry, enhanced cell differentiation and function, and improved drug testing.
Here we highlight the leading 3D culture models actively being used in research.
Spheroid Culture
In the 3D spheroid model, cells form a multicellular, multi-layered structure whose physical and biochemical features resemble a solid tumor mass.
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Depending on the cell type, spheroids have been observed to form three distinct architectures: tight spheroids, compact aggregates, and loose aggregates.
Non-adhesive conditions also promote cells to aggregate into spheroids.
Spheroid cell aggregates can better mimic the natural cell-to-cell interactions and the formation of nutrient and oxygen gradients in tissues
in vivo.
Spheroid models have become useful tools in studying complex processes.
Cell-based assays on cell migration, tissue invasion, and angiogenesis can be performed using spheroids.
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Due to their ability to mirror tumor heterogeneity, spheroids derived from tumor cell lines or primary tumor cells (sometimes called tumoroids) are used extensively in cancer research.
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Compared to other 3D models, spheroids can be less expensive and relatively easier to set up, making them ideal for high-throughput assays, such as drug screening.
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To grow spheroids,
ultra-low attachment
vessels, such as plates and flasks, are commonly used.
These reduce cellular adhesion to the vessel surface, promoting cell aggregation into spheroids.
Depending on the cell type, spheroids can be cultured scaffold-free, or in the presence of a 3D scaffold, such as hydrogels.
Hydrogels
can mimic the extracellular matrix (ECM) that provides structural support and an
in vivo-like environment for cells to grow in 3D.
Browse our catalog of specialized
spheroid culture media
from different manufacturers.
Organoid Culture
The organoid model is a 3D culture model that mimic the structures and functions of organs
in vivo.
For example, intestinal organoids can form crypt-villus structures and exhibit peristaltic movements, while brain organoids can develop neural networks and exhibit electrical activity.
Organoids develop from stem cells or organ-specific progenitors via self-organization and can be classified as stem cell or tissue organoids.
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They can comprise multiple cell types found in the organ they mimic. A liver organoid, for instance, will contain hepatocytes, bile duct cells, and endothelial cells.
Organoids are valuable tools for many basic research and clinical research areas, including developmental biology, disease modeling, infectious disease, regenerative medicine, and tumor biology.
Functional organoid models have been established to represent many tissues, including the thyroid, pancreas, liver, stomach, intestine, heart, cerebral cortex, thymus, kidney, lung, and retina.
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They are also useful in patient-relevant
in vitro models as they represent the original tissue’s genetic, phenotypic, and disease characteristics.
Patient-derived organoids can be used to conduct screening with high throughput.
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Like spheroids, organoids often require 3D scaffold support, which can come as a synthetic hydrogel or an animal-component-derived ECM.
Some organoids can also be grown as monolayers on membrane
inserts.
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Reagents such as
basement membrane extracts,
an important component of the ECM, have become widely used as core components of organoid culture.
They are commonly extracted from preparations of Engelbreth-Holm-Swarm (EHS) mouse sarcoma, which are rich in ECM proteins.
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Explore our catalog of specialized media and reagents
dedicated to growing organoids.
Organs-On-A-Chip
The Organ-on-a-Chip model is a type of microphysiological system, which employs microfluidics to recreate
in vivo cell and tissue microenvironments in an organ-specific context.
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The model can recreate interfaces between tissues and exert precise control over fluid flow and mechanical forces.
These mechanics are particularly relevant in complex
in vivo interactions, such as among immune cells, the microbiome, and exposure to clinical compounds.
As Organ-on-a-chip technology advances as a 3D culture model, researchers can anticipate its increased adoption across various platforms.
3D Bioprinting
3D bioprinting technology organizes cells and bio-compatible materials layer by layer to create three-dimensional structures that imitate the architecture and function of natural tissues and organs.
3D bioprinters
are used to gently distribute cells throughout ‘bio-ink’, often generated by a hydrogel, within defined spaces while preserving cell function and viability.
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3D bioprinting platforms have been used to construct a variety of specialized tissues, including engineered myocardial grafts, native heart valves, and musculoskeletal, neural, skin, and bone tissues.
Bioprinting can also be used to improve the assembly of organoids.
7 Bioprinters can be broadly categorized as inkjet-based, laser-assisted, extrusion-based, and electric field-based.
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Learn more about 3D bioprinting here.
For more information, visit our 3D Cell Culture Resources page.
References
1. Kapalczynska M, Kolenda T, Przybyla W, et al. 2D and 3D cell cultures - a comparison of different types of cancer cell cultures. Arch Med Sci. 2018;14(4):910-919. doi:10.5114/aoms.2016.63743
2. Cacciamali A, Villa R, Dotti S. 3D Cell Cultures: Evolution of an Ancient Tool for New Applications. Front Physiol. 2022;13:836480. Published 2022 Jul 22. doi:10.3389/fphys.2022.836480
3. Easthope E. Cell-Based Assays: How to Decide Between 2D and 3D. Biocompare. 2024 Jan 30 [cited 2024 Jul]. Available from: https://www.biocompare.com/Editorial-Articles/609617-Cell-Based-Assays-How-to-Decide-Between-2D-and-3D/
4. Smith C. Getting Started with 3D Cell Cultures. Biocompare. 2024 Feb 22 [cited 2024 Jul]. Available from: https://www.biocompare.com/Editorial-Articles/610998-Getting-Started-with-3D-Cell-Cultures/
5. Ewart L, Apostolou A, Briggs SA, et al. Performance assessment and economic analysis of a human Liver-Chip for predictive toxicology. Commun Med (Lond). 2022;2(1):154. Published 2022 Dec 6. doi:10.1038/s43856-022-00209-1
6. Carter N, Durban VM. A Three-Pillar Approach to Driving Organoid Adoption in Drug Discovery. Biocompare. 2024 Jan 29 [cited 2024 Jul]. Available from: https://www.biocompare.com/Editorial-Articles/610434-A-Three-Pillar-Approach-to-Driving-Organoid-Adoption-in-Drug-Discovery/
7. Easthope E. Bioprinting Applications, Tools, and Tips for Success. Biocompare. 2022 Aug 18 [cited 2024 Jul]. Available from: https://www.biocompare.com/Bench-Tips/589139-Bioprinting-Applications-Tools-and-Tips-for-Success/
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