Exam 3 Lecture 16: Bacterial Immunity

Question 1

What are the 5 routes of infection for pathogens
How do these impact the different mitigation strategies for different infections?

Answer 1

Aerosol (inhalation)
Oral (food or waterborne)
Vector borne (fleas, ticks, mosquitoes)
Fomites (inanimate objects)
Zoonotic (aniamls)

Question 2

What innate immune mechanisms control bacterial infection?

Answer 2

Complement cascade
Defensins
Commensal bacteria
Macrophages & neutrophils

Question 3

What T cell subsets play important roles during bacterial infections?

Answer 3

Intracellular infection: CD8+, Th1,
Extracellular infection: CD4+, Th17
Antibody activation: Tfh

Question 4

What role do antibodies play during bacterial infections?

Answer 4

Activating complement
Opsonization
Neutralization (of toxins)

Question 5

What are 4 different bacterial immune evasion strategies and which bacteria uses each one?

Answer 5

1. Surface antigen evolution & variability (ex. streptococcus pneumoniae)
2. Phagosomal escape to cytosol (ex. listeria monocytogenes)
3. Block phagsome/lysosome fusion (ex. legionella pneumonophila & mycobacterium tuberculosis)
4. Produce superantigens that lead to excessive immune response (ex. staphylococcus aureus)

Question 6

What are some examples of the species that can be infected by mycobacterial infections?

Answer 6

Humans, fish, cattle, deer, elephants, squirrels etc.

Question 7

What function do granulomas serve during mycobacterial infection?

Answer 7

Site of containment and growth for mycobacteria
-Infected macrophage core, Lymphocytic cuff, Macrophages fuse into, multinucleated giant cells, Often a necrotic or caseous core