Nature: the New Immunity Pathway was Confirmed
Our immune system is a natural defense that keeps harmful things out in normal conditions. But of course, this defense won’t always work.
Overall, our immune system works by differentiating normal things from abnormal things, such as between cells and microbes. While in terms of microbes, there are a lot of beneficial microbes, such as in gut, which must be distinguished from pathogenic microbes regarding to the fact that microbes are more predominant than cells in our body.
Illustrating as Salmonella, scientists researched the strain in both cell lines and animal models to find out how our innate immune system recognizes the pathogenic attack. Prior to this, people have assumed that GTPase activation might be the trigger, but without identified clue until this study.
Salmonella uses a secretion system, a type of molecular syringe, to inject pathogenic proteins, such as SopE, into the cell. SopE activates human GTPase enzymes RAC1 and CDC42, which break down the surrounding actin, allowing the bacterium inside. By this action, a protein—NOD1 was alarmed and then it sent signal to other proteins. Ultimately, this signaling pathway reaches the protein NF-κB, a transcription factor that instructs the genome to mount an immune response, activating genes associated with inflammation, neutrophils and other immune functions.
The new finding confirmed the earlier assumption about the role of protein NOD1 in our immune system and might led to new regimens for fighting immune system diseases.
Article Link: Nature: the New Immunity Pathway was Confirmed
Tags: Innate Immunity, RAC1, CDC42, NOD1, NF-κB