The whole process of obtaining human tissue for studying organ development and diseases is tedious due to ethical concerns and difficulty of availability. 3D cell culture offers a unique alternative for advanced research on human tissue. 3D cell culture, in the form of organoids, is used by biomedical researchers to study the complex arrangements and interactions of cells in 3D for studying diseases, physiology, drug toxicity, etc.
What are Organoids?
Organoids are an assembly of lab-grown cells that have organized into cellular structures similar to different organs. “Organoid” means “organ-like”. To provide an example, brain organoids can develop layers of active neurons and have similar regions similar to some ‘brain regions’. In the current research scenario, organoids can closely resemble some structural aspects but do not fully mimic the functional aspect of organs. Though these organoids might be small or just have some similarities to the fully furnished organs, researchers can learn a great deal from these structures. The current research generation believes that organoids are the ‘next-gen’ biological tools for biomedical studies.
How Organoids are Constructed?
Organoids start from stem cells. Different types of stem cells are used depending on what type of organoid is constructed. Scientists can use pluripotent or multipotent stem cells as different stem cells have different abilities and limitations. Protocols for growing organoids require researchers to formulate the requirements of specific growth conditions with nutrients, growth factors, signaling molecules. The growth conditions stimulate stem cells to differentiate into the cell lineage that relates to the intended organoid. The real challenge in organoid formation is to figure out the precise conditions of cell stimulation that promote stem cell differentiation and assembly.
Applications of Organoids
Researchers want to study organoids for several reasons. The first and foremost reason involves understanding what external factors direct stem cells to make organ-specific growth and development. Once the part of ‘making’ an organoid is done, the focus shifts on application. Once researchers can establish functional and phenotypical similarities between organ and organoid structures, they can use it to study several domains like drug toxicity, wound healing, genetic engineering, etc.
As an example, in a 2013 study, intestinal organoids created from 6 patients with multiple intestinal atresia disordered to the discovery of a crucial gene involved in intestine formation. The study reported that these patients carried single-gene mutations, causing discrepancy in the formation of healthy organoids from intestinal stem cells. The researchers were also able to determine the signaling pathway affected by the mutated protein in stem cells. In another study, brain organoids were used to study the ZIKA virus in brain development and microencephaly. In other cases, organoids can be excellent platforms to study infectious diseases or developmental biology.
- The Ethics of Brain Organoids– interview with bio-ethicist Sarah Chan
- ISSCR – Organoids: What is the Science and What are the Clinical Applications?– a YouTube video of a lecture on brain organoids
- TEDx Talk – How We Are Growing Organs in the Lab?– a YouTube video by Dr. Jim Wells
- HSC – Organoids: A new window into disease, development and discovery– an article on organoids by Harvard Stem Cell Institute
Organoids are the first step towards constructing fully functional organs in vitro and although researchers are far away from this ultimate goal, studies prove positive progress. If your lab is working on 3D cell culture organoids or spheroids, and you are looking for human stem cells, contact KOSHEEKA at firstname.lastname@example.org for your inquiries.