A nomenclature consensus for nervous system organoids and assembloids 公告 2024-12-16 08:45:43 Written By Kym Kilbourne Title: A Nomenclature Consensus for Nervous System Organoids and Assembloids Abstract One of the most remarkable scientific advancements in the field of stem cell research is the immense potential for human pluripotent stem cells to self-organize in laboratory settings. These three-dimensional (3D) cellular models, derived from human pluripotent stem cells or primary tissues, are crucial for gaining insights into how the human nervous system develops, its uniqueness, and the origins, progression, and potential therapeutic approaches for neurological disorders. To foster scientific progress and improve communication with the scientific community and the public, we have clarified and provided a foundational framework for the nomenclature of human multicellular nervous system development and disease models, including organoids, assembloids, and grafts. Defining Key Concepts The focus of our discussion is on the three main types of 3D models currently used in the field: organoids, assembloids, and grafted organoids. We define organoids as in vitro cellular systems that arise through self-organization, contain multiple cell types, and exhibit some cellular architectural and functional features reminiscent of an organ or organ region. Organoids can be generated as 3D cultures or through a combination of 3D and 2D methods (also known as 2.5D), and they can develop and mature over extended periods (months to years). Working Classifications We recognize two broad categories of neural organoids based on the level of guidance provided during their derivation from pluripotent stem cells. If the differentiation is unguided, leading to organoids that contain a high diversity of neural cells, typically representing different positions along the neuraxis as well as non-neural derivatives, we term them unguided neural organoids. If organoids are obtained by selecting parts of the organoid, such as using genetic reporters, cell sorting, or mechanical dissection (e.g., germinal zone or optic cup structures), we refer to these as selected neural organoids. Conversely, when guidance cues are used to generate organoids composed of more regionally specific cell types, we term them regionalized neural organoids, which can recapitulate cellular, molecular, or anatomical features of specific domains within the nervous system. General Recommendations To facilitate the current and upcoming nomenclature framework, we propose the following guidelines to promote clarity and rigor. Unless strong evidence is provided for recapitulating a specific domain, neural organoids should be named as broadly as possible (e.g., spinal cord, hindbrain, or arcuate nucleus). In the absence of evidence demonstrating characteristics of these cells or regions, there is a preference for descriptive naming conventions. For instance, if such evidence is lacking, organoids should be defined by regional axes (e.g., ventral-dorsal or anterior-posterior) and specify their cellular composition (e.g., the proportion of GABAergic or glutamatergic neurons). Final Comments We agree to implement this nomenclature system in our publications and invite others to align with this framework and provide input as the field evolves. We believe that nomenclature should remain flexible to accommodate new developments and information and should be updated as necessary. Looking ahead, new names may be required, but for now, we recommend avoiding excessive renaming. Importantly, we believe that work involving human cells must maintain close dialogue with ethicists and the broader scientific and non-scientific communities. Public support depends on trust that all who communicate discoveries, including scientists, institutional public relations departments, and science journalists, can accurately report and describe these structures and their uses. Emotionally charged descriptive terms can generate considerable attention and may harm scientific progress. Exaggerating or hyping discoveries is detrimental to the credibility of the field and ultimately undermines efforts to find urgently needed treatments for neurological diseases and disorders. We are excited about the potential of human multicellular models in understanding development, evolution, and neurological disease. We hope this framework will facilitate communication within and outside the field, catalyze further discussion, and accelerate progress. Kym Kilbourne
A nomenclature consensus for nervous system organoids and assembloids 公告 2024-12-16 08:45:43 Written By Kym Kilbourne Title: A Nomenclature Consensus for Nervous System Organoids and Assembloids Abstract One of the most remarkable scientific advancements in the field of stem cell research is the immense potential for human pluripotent stem cells to self-organize in laboratory settings. These three-dimensional (3D) cellular models, derived from human pluripotent stem cells or primary tissues, are crucial for gaining insights into how the human nervous system develops, its uniqueness, and the origins, progression, and potential therapeutic approaches for neurological disorders. To foster scientific progress and improve communication with the scientific community and the public, we have clarified and provided a foundational framework for the nomenclature of human multicellular nervous system development and disease models, including organoids, assembloids, and grafts. Defining Key Concepts The focus of our discussion is on the three main types of 3D models currently used in the field: organoids, assembloids, and grafted organoids. We define organoids as in vitro cellular systems that arise through self-organization, contain multiple cell types, and exhibit some cellular architectural and functional features reminiscent of an organ or organ region. Organoids can be generated as 3D cultures or through a combination of 3D and 2D methods (also known as 2.5D), and they can develop and mature over extended periods (months to years). Working Classifications We recognize two broad categories of neural organoids based on the level of guidance provided during their derivation from pluripotent stem cells. If the differentiation is unguided, leading to organoids that contain a high diversity of neural cells, typically representing different positions along the neuraxis as well as non-neural derivatives, we term them unguided neural organoids. If organoids are obtained by selecting parts of the organoid, such as using genetic reporters, cell sorting, or mechanical dissection (e.g., germinal zone or optic cup structures), we refer to these as selected neural organoids. Conversely, when guidance cues are used to generate organoids composed of more regionally specific cell types, we term them regionalized neural organoids, which can recapitulate cellular, molecular, or anatomical features of specific domains within the nervous system. General Recommendations To facilitate the current and upcoming nomenclature framework, we propose the following guidelines to promote clarity and rigor. Unless strong evidence is provided for recapitulating a specific domain, neural organoids should be named as broadly as possible (e.g., spinal cord, hindbrain, or arcuate nucleus). In the absence of evidence demonstrating characteristics of these cells or regions, there is a preference for descriptive naming conventions. For instance, if such evidence is lacking, organoids should be defined by regional axes (e.g., ventral-dorsal or anterior-posterior) and specify their cellular composition (e.g., the proportion of GABAergic or glutamatergic neurons). Final Comments We agree to implement this nomenclature system in our publications and invite others to align with this framework and provide input as the field evolves. We believe that nomenclature should remain flexible to accommodate new developments and information and should be updated as necessary. Looking ahead, new names may be required, but for now, we recommend avoiding excessive renaming. Importantly, we believe that work involving human cells must maintain close dialogue with ethicists and the broader scientific and non-scientific communities. Public support depends on trust that all who communicate discoveries, including scientists, institutional public relations departments, and science journalists, can accurately report and describe these structures and their uses. Emotionally charged descriptive terms can generate considerable attention and may harm scientific progress. Exaggerating or hyping discoveries is detrimental to the credibility of the field and ultimately undermines efforts to find urgently needed treatments for neurological diseases and disorders. We are excited about the potential of human multicellular models in understanding development, evolution, and neurological disease. We hope this framework will facilitate communication within and outside the field, catalyze further discussion, and accelerate progress. Kym Kilbourne
