Test 2: Immunity to Infections Flashcards
What type of immune response is elected by extracellular bacteria?
complement, phagocytes, Ig
What mechanisms of innate immunity are there to extracellular bacteria?
- complement activation
- opsin/phagocytosis
- stimulation of inflammatory reactions via anaphylatozxin
What do Ig induce in humoral immunity to extracellular bacteria?
opsonization and phagocytosis and complement activation
What do bacterial protein antigens processed by dendritic cells activate?
- CD4 helper T cells for:
production of IL-17 and neutrophil recruitment and production of IFNy and activation of macrophages and B cell help
How do CD4 T cells differentiate into Th1 effectors?
via IL-12
Macrophages are activated by?
T cell derived signals= IFNy
In innate immunity to fungi, what is protective?
- ILC1 and ILC3 are protective
- Th1 and Th17 responses are protective
T/F: Wearing upper dentures or dry mouth increase risk of oral candidiasis
True!
What is the first immune response against viruses?
Innate immunity: IFNa and NK cell killing
What is the weakness/limitation in parasite immunity?
weak innate immunity
What specific adaptive immunity do we want for protozoa?
macrophage activation by Th1 cell-derived cytokines
What responds against lytic protozoa (malaria)?
CTL responds
What specific adaptive immunity do we want for helminths?
activation of Th2 cells results in killing of helminth not infected cells
- production of IL-4 which induces IgE
- production of IL-5 which stimulates eosinophil development and activation
- degranulation of eosinophils and killing of helminth via release of major cationic protein and major basic protein
How microbes evade immune response?
3 ways:
- antigenic variation
- inhibition of complement activation
- resistance to phagocytosis
What is the common evasion mechanism for bacteria, viruses, and parasites?
antigenic variation
