Difference Between Organoids and Spheroids

The key difference between organoids and spheroids is that organoids are 3D cell cultures that are most frequently grown on a scaffold-based system, while spheroids are 3D cell cultures that are grown on a scaffold-free system.

Organoids and spheroids are two types of 3D cell cultures. A 3D cell culture is a cluster of biological cells grown in an artificially created environment. These biological cells are permitted to grow or interact with their surroundings in all three dimensions. 3D cell cultures are broadly divided into two types: scaffold-based system and scaffold-free system. Scaffold-based system uses natural or synthetic material as a support for seeded cells to aggregate, proliferate, and migrate. In contrast, a scaffold-free system encourages self cell aggregation via specialized culture plates or physical parameters that prevent cell attachment.

CONTENTS

1. Overview and Key Difference
2. What are Organoids 
3. What are Spheroids
4. Similarities – Organoids and Spheroids
5. Organoids vs Spheroids in Tabular Form
6. Summary

What are Organoids?

Organoids are 3D cell cultures that are most frequently grown on a scaffold-based system. They are miniaturized versions of organs grown in vitro in three dimensions. They show realistic microanatomy. Organoids are normally derived from a single adult stem cell or embryonic stem cell. They can also be produced from induced pluripotent stem cells such as skin or blood cells. These cells can self assemble when they are given scaffolding extracellular environments such as Corning® Matrigel® matrix of collagen. Ultimately, they grow into microscopic versions of parent organs that are viable for 3D research studies. The technique of generating organoids rapidly has improved since 2010. The Science journal named this technique as one of the biggest scientific advancements of 2013. The main usages of organoids are to study diseases and treatments in laboratories.

Furthermore, some examples of organoids are cerebral organoid, gut organoid, intestinal organoid, stomach or gastric organoid, lingual organoid, thyroid organoid, thymic organoid, testicular organoid, and hepatic organoid.

What are Spheroids?

Spheroids are 3D cell cultures that are grown on a scaffold-free system.  They consist of cell aggregates generated from a single cell type or from a multicellular mixture of cells. Spheroids can be established from immortalized cell lines, primary cells, or fragments of human tissue. They are simple clusters of broad-ranging cells such as embryoid bodies, hepatocytes, tumor tissue, nervous tissue, or mammary glands.

Spheroids don’t require scaffolding to form 3D cell cultures. In these spheroids, low adhesion culture conditions can use to promote self-aggregation of cells into sphere-shaped 3 dimension structures. They do it so by normally sticking to each other. Spheroids can also be cultured using other different methods like the hanging drop method and rotating wall vessel bioreactors. Nevertheless, they cannot self assemble or regenerate. Thus, spheroids are not as advanced as organoids.

What are the Similarities Between Organoids and Spheroids?

1. Organoids and spheroids are 3D cell cultures.
2. Both are grown in in vitro laboratory conditions.
3. They are viable cell cultures.
4. Both can be generated from a variety of healthy tissues as well as diseased cell types and tissues such as tumors.
5. They are used to study diseases and treatments.

What is the Difference Between Organoids and Spheroids?

Organoids are 3D cell cultures that are most frequently grown on a scaffold-based system, while spheroids are 3D cell cultures that are grown on a scaffold-free system.  So, this is the key difference between organoids and spheroids. Furthermore, organoids can self assemble and regenerate, whereas spheroids cannot self assemble and regenerate.

The following figure lists the differences between organoids and spheroids in tabular form for side by side comparison.

Summary – Organoids vs Spheroids

The 3D cell culture is a culture environment that allows cells to grow and interact with their surrounding extracellular framework in three dimensions. Organoids and spheroids are two types of 3D cell cultures. Organoids are 3D cell cultures that are most frequently grown on a scaffold-based system, while spheroids are 3D cell cultures that are grown on a scaffold-free system.  Thus, this is the summary of the difference between organoids and spheroids.

Reference:

1.“Organoid.” An Overview | ScienceDirect Topics.
2. Białkowska, Kamila, et al. “Spheroids as a Type of Three-Dimensional Cell Cultures-Examples of Methods of Preparation and the Most Important Application.” International Journal of Molecular Sciences, MDPI, 28 Aug. 2020.

Image Courtesy:

1. “Cerebral organoid flowchart” By keval_tilva – Own work (CC BY-SA 3.0) via Commons Wikimedia
2. “Hepatocyte spheroid, imaged with Lightsheet Z.1” By ZEISS Microscopy  (CC BY-NC-ND 2.0) via Flickr