(1)How would your body react in a non-specific way to a threat of microbial invasion
(2)How would your body react in a specific way to a viral invasion?
(3)Describe how memory cells contribute to immune protection?
(1) Once a microbial pathogen enters the body, there are several non-specific mechanisms the body can use to defend itself. Firstly, physical barriers such as skin or mucus the gut or respiratory tract can prevent the organism from entering the body. If the pathogen is able to penetrate into the body, it is the job of the innate immune response to recognize the pathogen as a foreign entity and initiate an immune response against it.
Cells of the innate immune system, particularly dendritic cells and macrophages, express receptors known as pattern recognition receptors. These receptors, the most well-studied of which are the Toll-like receptors (TLRs), recognize common patterns in proteins or DNA that are present in a large variety of pathogens but absent from normal tissues. For example TLRs can recognize protein patterns common in bacterial flagellae, or endotoxins such as lipopolysaccharide (LPS), both of which are specific for bacteria. Other TLRs are inside the cell and can recognize nucleic acid that is ...
This solution describes in detail both non-specific and specific defense mechanisms against pathogens. It describes innate and adaptive immunity to infection, and how memory cells act to provide long-term immunity.