In a new study, researchers from the Chinese Academy of Sciences Shenzhen Institute of Advanced Technology, Jinan University, Shenzhen University, Fudan University, Xiamen University, Israel Weizmann Institute of Science and other research institutions revealed the dynamic changes in the differentiation of human macrophages in 19 different tissues from the early embryonic stage. The relevant research results were published online in the Cell journal on September 12, 2023, with the title "An immune cell atlas reviews of the dynamics of human macrophage specification during preliminary development".
As a key type of immune cell, the diversity and role of macrophages in human development have long been a mystery. Based on the research results of rodents, the scientific community has gained some understanding of the diversity, developmental origin, and tissue-specific formation of macrophage subtypes. However, it is unclear whether these findings have been preserved in humans.
In this new study, these authors combined single-cell transcriptome sequencing, bioinformatics techniques, immunofluorescence, and in vitro functional testing to construct a high-resolution spatiotemporal dynamic map of human prenatal immune system development spanning 18 pregnancy periods (4th to 26th weeks after conception) and 19 tissues.
Based on this graph, these authors focused on studying the most tissue-specific cell lineage - macrophages. They revealed the differentiation origin, spatial localization, functional characteristics, and transcriptional regulation mechanisms of various macrophage subtypes during development.
Li Hanjie, the co corresponding author of the paper and professor of the Chinese Academy of Sciences Shenzhen Institute of Advanced Technology, said, "The main finding of our research is that we have identified 15 different macrophage subtypes, with special attention paid to two new macrophage populations: microglia like cells and proangiogenic macrophages (PraM)."
As a key type of immune cell, the diversity and role of macrophages in human development have long been a mystery. Based on the research results of rodents, the scientific community has gained some understanding of the diversity, developmental origin, and tissue-specific formation of macrophage subtypes. However, it is unclear whether these findings have been preserved in humans.
In this new study, these authors combined single-cell transcriptome sequencing, bioinformatics techniques, immunofluorescence, and in vitro functional testing to construct a high-resolution spatiotemporal dynamic map of human prenatal immune system development spanning 18 pregnancy periods (4th to 26th weeks after conception) and 19 tissues.
Based on this graph, these authors focused on studying the most tissue-specific cell lineage - macrophages. They revealed the differentiation origin, spatial localization, functional characteristics, and transcriptional regulation mechanisms of various macrophage subtypes during development.
Li Hanjie, the co corresponding author of the paper and professor of the Chinese Academy of Sciences Shenzhen Institute of Advanced Technology, said, "The main finding of our research is that we have identified 15 different macrophage subtypes, with special attention paid to two new macrophage populations: microglia like cells and proangiogenic macrophages (PraM)."
Image from Cell, 2023, doi: 10.1016/j.cell.2023.08.019.
Surprisingly, microglia like cells were found in unexpected locations such as the fetal epidermis, testicles, and heart, similar to microglia in the central nervous system. These authors found that these cells can affect the differentiation of neural crest cells, thereby promoting early tissue development.
These authors also emphasized the strategic location of proangiogenic macrophages in the perivascular area of different fetal organs. These macrophages can originate from the yolk sac and play a crucial role in the development of blood vessels during the prenatal stage.
Dr. Wang Zeshuai, co first author of the paper and a guest student of the Chinese Academy of Sciences Shenzhen Institute of Advanced Technology, said, "Our research provides a comprehensive map of the diversity and development process of human macrophages, revealing their multiple roles in the development process. These findings will completely change our understanding of these immune cells and provide a promising way for potential therapeutic intervention."
These authors also emphasized the strategic location of proangiogenic macrophages in the perivascular area of different fetal organs. These macrophages can originate from the yolk sac and play a crucial role in the development of blood vessels during the prenatal stage.
Dr. Wang Zeshuai, co first author of the paper and a guest student of the Chinese Academy of Sciences Shenzhen Institute of Advanced Technology, said, "Our research provides a comprehensive map of the diversity and development process of human macrophages, revealing their multiple roles in the development process. These findings will completely change our understanding of these immune cells and provide a promising way for potential therapeutic intervention."
