"Character low-key but high-profile"! Nature reveals 'big role' of human structural cells in immune regulation

The immune system can protect our bodies from viruses, bacteria and other pathogens.generally speaking, it is the "national defense force" of the body, which is responsible for defending against foreign aggression.most of this protection is provided by the "army" of hematopoietic immune cells, which are derived from bone marrow and are specialized in fighting pathogens."army" members include macrophages (which can remove pathogens), T cells (which kill infected virus producing cells) and B cells (producing antibodies that neutralize pathogens).of course, immune function is not limited to these "experts", but more types of cells can sense when they are infected and participate in the immune response against pathogens.Image Source: rob dobi / CeMM structural cells are just like this.it is an important part of the human body and plays an important role in shaping the structure of tissues and organs.for example, epithelial cells form the surface of the skin and also separate tissues and organs from each other; endothelial cells wrap all blood vessels; fibroblasts provide connective tissue to keep tissues and organs in shape.structural cells have always been "low-key" and are considered to be simple and uninteresting parts of the human body.but we can't underestimate it. It plays an important role in autoimmune diseases (such as rheumatoid arthritis and inflammatory bowel disease) and cancer.Thomas krausgruber, Nikolaus fortelny and their colleagues from the Christoph bock Laboratory of the Research Center for molecular medicine of the Austrian Academy of Sciences (CeMM), tried to enter this low-key but high-profile "big guy".in their latest research, they carried out systematic and genome-wide analysis on epigenetic and transcriptional regulation of human structural cells to clarify the role of structural cells in immune regulation.the results were published in the journal Nature.specifically, CeMM researchers used high-throughput sequencing technology (RNA SEQ, ATAC SEQ, chipmentation) to sequence three structural cells (epithelial cells, endothelial cells, fibroblasts) from 12 organs of healthy mice, and established a comprehensive catalog of immune gene activity of structural cells.this data set reveals the extensive expression of immune genes in structural cells, as well as the high cell type and organ specificity of gene regulation patterns.bioinformatics analysis detected the genes controlling the complex interaction network between structural cells and hematopoietic immune cells, revealing the potential mechanism of structural cells participating in the response to pathogens.interestingly, many immune genes exhibit epigenetic characteristics that are usually associated with high gene expression, while the expression observed in structural cells obtained from healthy mice is lower than expected based on epigenetic characteristics. therefore, the CeMM researchers hypothesized that these genes were pre programmed epigenetically and that they were rapidly up-regulated when their activity was needed, such as in response to pathogens. to test this hypothesis, they used their expertise in viral immunology and infection biology to work with the Andreas bergthaler Laboratory of CeMM. the results were not unexpected. When mice were infected with the virus that triggered a broad immune response (LCMV), many epigenetic genes that were ready to be activated were up-regulated and promoted transcriptional changes in structural cells in response to viral infection. these results suggest that structural cells achieve an "epigenetic potential" that can be pre programmed to participate in rapid immune responses. as another test, the researchers triggered the artificial immune response by injecting cytokines into mice, and indeed found that many of the same genes were up-regulated. in conclusion, this new study reveals the astonishing complexity of immune gene regulation in structural cells. these results indicate that structural cells are not only an essential part of the human body, but also play a broad role in the body's defense against pathogens. in addition, the data provided help to develop innovative therapies for many diseases involving the immune system. end reference: [1] smart structures: structural cells of the body control immune function