Several international research groups have analyzed the hitherto underexplored populations of immune cells —compared to those circulating in the blood—in multiple tissues of the human body to provide new insights into the functioning of our immune system.
The first of these works focuses on the early development of the immune system and the localization of immune cells in various tissues. The second examined immune cells in various tissues of adult subjects, providing a framework for predicting cell type identity and understanding immunological memory.
Both are part of the international consortium Atlas of Human Cells (HCA), whose goal is to map all types of cells in the human body to understand human health and diagnose, monitor and treat disease. HCA is open-minded and led by scientists; Different institutes will collaborate in it and have funding from all over the world, with more than 2,300 members from 83 countries.
These studies explore the similarities and differences of immune cells in different tissues. Knowing the reactions of immune cells in these tissues, at different stages of life, can help to improve therapies aimed at producing or potentiating an immune response to fight the diseaselike the vaccines or treatments for Cancer.
In addition, the magazine Science echoes two other investigations that created comprehensive, open-access tissue cross-sectional cell atlases that will also contribute to the creation of a unique Human Cell Atlas.
The complexity of the immune system
The human immune system is made up of many different types of cells that are found throughout the body and that perform crucial functions. They don’t just fight pathogens when they appear, but remember them so they can be removed in the future.
The Wellcome Sanger Institute and its collaborators have created an atlas of the development of the human immune system in nine organs. For this, they used the space transcriptomics to know the cellular diversity of tissues, and single cell RNA sequencing map the exact location of specific cells within developing tissues.
Scientists have identified a new type of distinct B and T cells that appear early in life. The team used data from another Human Cell Atlas study to show that these specific immune cells are not found in adults.
Muzlifah Hannifah, by Wellcome Sanger and the University of Newcastle, and one of the lead authors of the first paper, explains: disorders. In collaboration with the other studies, it makes it possible to map the immune system from development to adulthood.”
A Cellular Catalog of the Adult Human Body
In the second study, scientists at Wellcome Sanger, the University of Cambridge and other centers simultaneously analyzed immune cells from 16 tissues from 12 adult organ donors. The team also developed a database and an algorithm that automatically classifies different types of cells, called Cell Typist, to deal with the large volume and variation of immune cells. In this way, they were able to identify about 100 different cell types.
In this way, they revealed the relationship between immune cells in one tissue and their counterparts in others, to the point of finding similarities between certain families of immune cells, such as macrophages, as well as differences in others. For example, some memory T cells exhibit unique characteristics depending on the tissue in which they are found.
“We have created a catalog of immune cells within the adult human body, allowing us to automatically identify cell types in various tissues. We want to thank the donors and their families who made this research possible,” he says. Count Cecilia Dominguezco-author of the second Wellcome Sanger study.
In addition to creating a new resource for researchers to classify different cell types, our work will have many implications, including providing a framework for developing therapies to fight immune-related diseases.
Per Joanne Jones, also a co-author from the University of Cambridge: “In this research, we not only identified different types of immune cells, but we also found that some types of immune cells follow specific distribution patterns in tissues. This could help inform research on diseases and how treatments targeting these cells can affect other tissues.”
“In addition to creating a new resource for researchers to classify different cell types, our work will have many translational implications, such as providing a framework for developing therapies to fight immune-related diseases and manage infections,” he concludes. Sarah Techmannlead co-author of both studies.
These atlas of cross-tissue immune cells are freely available to the research community.
Chenqu Suo, Emma Dann, Issac Goh, and others. Mapping the developing human immune system across organs. Science.
Count Domingues. C, Xu. C, Jarvis. LB, rainbow. DB, Wells. SB, and others. Analysis of immune cells between tissues reveals specific tissue characteristics in humans. Science.