GI immune system

Question 1

components of innate IS

Answer 1

pattern recognition receptors, antimicrobrail peptides, cells (macrophages, NK, dendritic, neutrophils, eosinophils (kill parasites), mast, NK-T), complement components and cytokines

Question 2

Pattern recognition receptors

Answer 2

proteins expressed by cells of the innate immune system to identify pathogen-associated molecular patterns (PAMPs), which are associated with microbial pathogens or cellular stress, as well as damage-associated molecular patterns (DAMPs), which are associated with cell components released during cell damage.

Question 3

Adaptive immune response

Answer 3

undergoes clonal expansion

Question 4

Antigen presentation

Answer 4

antigens internalised –> broken to peptides –> peptides with class II–> surface –> if foreign recognised by helper T-cells (CD8) –> cytokines

Question 5

Innate defences

Answer 5

flora, epithelial barrier (goblet cells, enterocytes and IgA) and biochemical factors

Question 6

Specific defences

Answer 6

lymphoid tissue e.g. GALT

Question 7

Mucosal follicles

Answer 7

aggregate in Peyer’s patches abd appendix

Question 8

Leukocytes

Answer 8

in lamina propria

Question 9

secretory IgA

Answer 9

prevents bacteria/toxins attacging to epithelia: –> secretion lactoperoxidase (antimicrobial agent) and lactoferrin (in mucosa) –> inhibits bacterial adhesion, macromoelcule absorptyion and inflammation effects other Igs
enhances non-specific defence mechanism