On November 20, international scientists announced the first design of the development of the human skeletal system, marking a significant advancement in the Human Cell Atlas project, a major effort to create a detailed biological map of every type of cell in the human body.
The Human Cell Atlas project was initiated in 2016 and currently involves researchers from around the globe. The project’s goal is to provide deeper insights into human health and assist in the diagnosis and treatment of diseases.
The human body contains approximately 37 trillion cells, each type having a special function. Scientists hope to complete the first draft of the cell map within the next 1 to 2 years.
Dr. Aviv Regev, co-founder and current Executive Vice President of Genentech (USA), stated that this project is important for two reasons. She explained: “First is the fundamental human curiosity. We want to know what we are made of. Humans have always wanted to understand the nature of themselves. In fact, biologists began mapping cells back in the 1600s for this reason. Second, there is a practical reason: we need this knowledge to understand and treat diseases. Cells are the basic units of life, and when problems occur, they often originate from the cells.”
The Human Cell Atlas project attracts participation from researchers worldwide. (Image source: technologynetworks.com).
In this project, researchers have completed a map of skeletal development during the first three months of pregnancy, describing all the cells, gene networks, and interactions related to the early development of bones. They demonstrated how cartilage serves as a “framework” for bone development, except for the top part of the skull. They also described the important cells involved in skull formation and studied how gene mutations can cause the soft spots on infants’ skulls to fuse too early, thereby limiting brain development.
According to the researchers, understanding these cells may help identify and treat congenital disorders. They also found that some genes activated in the first bone cells may be linked to the risk of developing hip arthritis in adulthood.
In addition to the skeletal system, researchers also published detailed maps of other organs in the body. One important map is of the digestive system, which includes tissues from the mouth, esophagus, stomach, intestines, to the colon. They discovered one type of cell in the intestine that may be related to inflammation, potentially offering new insights into diseases like Crohn’s disease and ulcerative colitis.
The thymus map – a vital organ for training immune cells to protect the body against infections and cancer – was also published by the scientists.
Dr. Alexandra-Chloe Villani from Massachusetts General Hospital (USA) remarked: “Although the primary focus of the project is mapping cells in healthy human bodies, this project has also provided valuable insights into diseases such as cancer, COVID-19, cystic fibrosis, and heart, lung, and intestinal diseases.”
The research in this project utilizes new data analysis tools, including artificial intelligence (AI) and machine learning. Dr. Sarah Teichmann from the Cambridge Stem Cell Institute (UK) stated that data from the Human Cell Atlas allows researchers to train basic models, similar to “ChatGPT for cells,” which helps identify and analyze new cells or search for cells among millions of cell records. Dr. Teichmann shared: “This helps us discover surprising connections, such as the link between cells in pulmonary fibrosis and cells in pancreatic tumors.”
Scientists believe that understanding human development at the cellular level is a significant challenge. Dr. Muzlifah Haniffa from Newcastle University (UK) noted: “These studies help us understand how tissues, organs, and the human body are built. Understanding human development is crucial in studying developmental disorders, congenital conditions, as well as diseases affecting adults, because these developmental pathways can re-emerge in later diseases.”
