A new model: miniature organs in biomedicine

Introduction

Within biomedicine, the study of diseases and understanding their mechanisms are crucial to the treatments we can develop for them. Before a treatment option can be rolled out to the general public, it must be tested for safety and efficacy. Usually, this testing takes place in the form of cell cultures or animal models. However, these methods cannot always accurately replicate the human body's complexity and physiological responses and are sometimes quite expensive and difficult to maintain. In the past few years, a new model has come to light known as organoids, allowing for a new realm of understanding into drug development, disease, and human biology.

What Are Organoids?

Organoids are self-organised, small, three-dimensional organ models which allow scientists and researchers to study different biological organs and tissues in a lab setting, including their physiological functions, development, and structure. These miniature organs are remarkable in their resemblance to actual organs and are obtained from stem cells, and they can undergo division to become any cell type. From their theoretical abilities, organoids may be able to serve utmost value in biomedicine and how we think about testing new treatments.

Disease Modelling, Drug Development and Personalised Medicine

One of the ways in which organoids can be used is to model diseases and test for potential drug targets and treatment programmes. In this way, researchers can replicate congenital and acquired conditions, such as cystic fibrosis and cancer, to study key target phenotypes and understand disease progression, which can help identify potential drug targets. From here, the efficacy of these therapeutics can be assessed quite quickly under different circumstances. 

As an example of this being used currently, scientists involved in cancer research have produced organoids from tumour cells stemming from cancer patients. These patient-derived organoids have been made for various cancers, including endometrium. They will allow for the ability to test chemotherapy drugs and determine which are most effective for individual patients whilst factoring in comorbidities and other unique factors to that person. Through this personalised approach, it is hoped that therapeutics will allow for a customised treatment programme which lowers the risk of side effects and improves the quality of care.

Understanding Development and Function

Another use of organoids is going into more depth and exploring our understanding of how an organ may develop and function. Using organoids can help us observe how different cells may work together and interact to organise themselves, allowing researchers to strengthen their knowledge of organogenesis by mimicking the natural growth conditions of the human environment.

By combining tissue engineering with an appreciation of an organ's functional and developmental processes, organoid use can be extended to regenerative medicine to help fill research gaps in the molecular and cellular mechanisms of tissue regeneration. Techniques such as ELISA and immunofluorescent staining can help garner these critical details. By achieving this, organoids may produce entire organs for transplantation, addressing the organ donor shortage and lowering the risk of donor rejection.

Recent Breakthroughs

Cardiovascular diseases are one of the leading causes of death around the world. The human heart is limited to regenerating damaged tissue; thus, research must explore using organoids and other cell-based therapies to encourage natural repair processes. By investigating this avenue, cardiomyocytes derived from human pluripotent stem cells are a promising source. These cell types have the potential to restore contractile functions in animal models as well as the ability to regenerate myocardial tissue. Researchers have developed a cardiac organoid with silicon nanowires that have significantly improved the medicinal efficacy of stem cell-derived cardiac organoids. Using these nano-wired organoids, electrical activity was shown to improve, which in turn supported improved contractility in ischemia-injured mice.

Challenges and Future Directions

While the promising nature of organoids must be acknowledged, they are not without limitations. Research is currently ongoing to improve the reproducibility and scalability of organoids and their cultures to make organoids more accessible and their use more widespread. Below are some summarised advantages and disadvantages of organoids.

Conclusion

In conclusion, the advent of organoids has created a revolutionary era within the scope of biomedicine. These miniature organs have remarkable potential in various research, development, and tissue engineering facets. Organoids provide scientists with precise modelling of diseases across a range of different organs, assuring their versatility. From understanding organ development to combating cardiovascular diseases and introducing personalised treatment for cancer patients, it is unclear why they are being more rapidly explored. While they hold their promise, there are still challenges surrounding their reproducibility, restricting them from being used in organ transplantation. However, with ongoing progress, organoids undoubtedly have the aptitude to tailor treatments and address complexities of tissue regeneration, heralding a groundbreaking era in healthcare.

By Irha Khalid

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