Nature interpretation! Protrusion cells may be able to cope with cancer through multiple threads.

!--webeditor: page title -- -- The production of an effective anti-cancer immune response is a multi-faceted, multi-step process, and in a recent study published in the international journal Nature, researcher Ferris et al. found that an immune cell called a dendritic cell is more flexible than previously thought in coordinating tumor targeting.
A key feature of the
immune cell targeting cancer process is the activation of CD8 T cells, which recognize antigens, peptide fragments derived from tumor cells, and the initiation of anti-tumor reactions also requires the action of degenerate cells, which can ingest Tumor-derived proteins are captured and processed into antigens, which can be displayed on their surfaces and combined with major tissue-compatible complex (MHC) molecules and presented to T-cell-like (TCR) molecules on T-cells.
another type of T cell called CD4 T cells (auxiliary T cells) is also able to identify antigens shown in a class of molecules called Class II MHC, which provides auxiliary signals to promote CD8 T cells to kill tumor cells, so that C D8 T cells can establish a long-lasting protection mechanism against tumor recurrence, and it is important to understand and control the body's anti-tumor immune response in clinically to clarify the molecular mechanism of which type of degeneration cells and CD8 T cells are stimulated by CD4 T cells.
Most of the results we know about immune responses, including anti-tumor responses, come from studies of infections, not cancers, in which two dendroid cells called DC1s and DC2s initially activate CD8 and CD4 T cells, respectively, and then both types of activated T cells once or at the same time Antigens on DC1s are identified, and CD4 T cells provide effective help to CD8 T cells; for example, CD4 T cells secrete special molecules to support the function of CD8 T cells, and CD4 T cells induce DC1s to express specific molecules, thereby enhancing the activation of CD8 T cells.
There is some debate between researchers about whether the interactions between CD4 and CD8 T cells and DC1s are simultaneous or sequential, in any way consistent with the conclusions of previous study models, which have previously concluded that DC1s must present both Class I and Class II MHC molecules to produce an immune response against infectious factors. Now living imaging technology can provide evidence that DC1s can act as a platform to support the activation of CD4 and CD8 T cells at the same time, but many studies have shown that DC1s can present antigens of Class I MHC molecules to CD8 T cells, while DC2s can present Class II MHC molecules to CD4 T cells.
photo source: Marianne Burbage et al. Nature (2020) doi: 10.1038/d41586-020-02339-9DC1s promote CD8 T cells to get help from CD4 T cells The platform model may not yet be clearly genetically supported by in vivo experiments, and the researchers say they used a model of fibroblastoma mice to assess the role that CD4 T cells in their bodies' different stages of anti-tumor immune response can help, and fibroblastoma stimulates the body to produce a strong immune response.
month after removing primary fibroblastoma after surgery, the researchers injected mice with the same type of cancer cells and monitored the growth of tumors, which were rejected in controlled animals and were 100% effective at being removed by immune cells. In the immune response of primary tumors, or in the memory immune response to secondary tumors, the removal of CD4 or CD8 T cells mediated by antibodies removes the immune system's control over secondary tumors, suggesting that CD4 T cells are necessary for both types of immune system responses.
The researchers then engineered fibroblastoma cells to express egg white proteins, providing a model system for monitoring immune responses, and wild mice were able to effectively reject these engineered tumor cells; In mice, a few days later, the researchers collected immune cells from the lymph nodes of mice, an engineered CD4 T cell that proliferates actively, suggesting that it can be activated by interacting with egg white protein antigens from tumors, compared with the same experiments in mice that were missing DC1s, which revealed a lack of CD4 T cell stimulation, suggesting that DC1s is also essential.
By genetically removing CD4 T cells from DC1s, the researchers may be able to reveal the role of proteins in promoting CD4 T cells to help CD8 T cell responses, however, the researchers did not clarify how CD4 T cells affect and license DC1s to activate CD8 T cells, in particular, to study whether interactions between DC1s and CD4 T cells regulate the expression of key immune cell regulators, such as examining the expression of point proteins or soluble molecules called cell factors.
, will DC1s also help enhance the anti-tumor immune response in the body? DC1s and DC2s play an evolutionaryly conservative role in the human body, and mice and human DC1s share many common functions and can express similar proteins, but there are also some species differences; In mouse bodies, DC1s produce more IL-12s than DC2s, but in humans, the opposite is true, and whether human DC1s are more effectively presented to CD8 T cells than DC2s remains a controversial issue.
Although many studies have shown that DC1s are critical to the human anti-tumor immune response, the evidence is still circumstantial or controversial, revealing the role of human DC1s is critical, and the results may help scientists develop new cancer immunotherapy clinically.
() !--/ewebeditor:page--!--ewebeditor:page title"--references: Ferris, S.T., Durai, V., Wu, R. et al. cDC prime and are licensed by CD4 plus T cells to toe anti-tummmunity. Nature (2020). doi: 10.1038/s41586-020-2611-3( 2) Marianne Burbage, Sebastian Amigorena. A dendritic cell multitasks to tackle cancer, Nature (2020) doi: 10.1038/d41586-020-02339-9 !--/ewebeditor:-page.