Microbes, Immunity, and Disease Flashcards
What causes her symptoms?
What determines recovery?
Why doesn’t everyone catch it?
Not all symptoms are caused by the actual pathogen. In fact, most of these symptoms are caused by the inflammatory and immune responses to the pathogen rather than the pathogen itself.
The virus may cause damage to cells when it exits the cells using the cellular membrane. Or bacteria may release toxic compounds that damaging surrounding cells.
But most of the ‘sick/ill’ sensations come as a result of your bodies reaction.
Recovery determines by immune system - ability to recognize and dispel the pathogen.
No teveryone catches it because some people already have antibodies that can immedaitely recognize the antigens of the pathogen, and so have a fast response and not get sick.
Microbes: what parts of viruses, bacteria, and parasites get recognized by the immune system?
Viruses: Viral surface proteins (like spike). When they are inside cells, parts othe virus may be presented on MHC molecules. Or the general cellular damaged caused by the cells invokes inflammation
Bacteria: Surface shapes like LPS. Cellular damage which elicits inflammation, and bacterial metabolites.
Parasites: cellular damage, surface proteins. However can be more difficult as parasites often have mutliple phases of a life cycle, so their shapes change.
