Immunity

Question 1

Myeloid Progenitors Include…

Answer 1

Basophils, eosinophils, neutrophils, macrophages, and dendritic cells

Question 2

Lymphoid progenitors include…

Answer 2

Bone Marrow
-B cells, Natural Killer (NK) cells
Thymus 
-CD4+ and CD8+ T cells
Dendritic cells, memory cells, activated T and B cells

Question 3

Complement Cascade Pathways

Answer 3

Classical pathway - antibody production
Lectin Pathway - mannose binding lectin
Alternate pathway

Question 4

Membrane Attach Complex

Answer 4

• Induced after PAMP-PRR interaction

- Causes opsonisation and chemotaxis inflammation

Question 5

B Cells

Answer 5

• Recognize free or soluble antigens

- Mucosal dendritic cells help stimulate IgA production through activation of Th2 cells

Question 6

T Cells

Answer 6

• Recognize MHC peptides

- Antigens are broken down to peptides and then presented on MHC

Question 7

MHC I

Answer 7

• Displayed on all nucleated cells

- Broken down inside the cells and then displayed

Question 8

MHC II

Answer 8

• Displayed only on Antigen Presenting Cells

- Proteins served from pathogens that are taken up through endocytosis and then displayed

Question 9

T-Cell Activation

Answer 9

1) MHC peptide presentation
2) Costimulatory CD80 and CD28 molecules interact with CD8
3) Cytokine secretion

Question 10

B-Cell Activation

Answer 10

1) Dendritic Cell (DC) is activated by pathogen
2) DC presents to and activates T cells (MHC)
3) T cells activate B cells as well as help with isotype switching and affinity maturation

Question 11

MALT

Answer 11

Mucosal associated lymphoid tissue

Question 12

GALT

Answer 12

Gastrointestinal associated lymphoid tissue

Question 13

Innate defenses of the gut

Answer 13

• Peristaltic action, mucos layer, epithelial integrity, antimicrobial factors, cytokines
• Lymphocytes, macrophages, dendritic cells

Question 14

Peyer’s Patches

Answer 14

Small patches of lymphoid tissue that keep the normal gut flora in check

Question 15

M Cells

Answer 15

Antigens in the gut lumen are sampled by microfold (M) cells and are delivered to gut associated lymphoid tissue

• Lack thick glycocalyx and do not secrete mucous go allow for the controlled uptake of antigens
• Don’t express MHC I
• Transport of antigens from lumen to sub-epithelial space

Question 16

Mucosal Dendritic Cells

Answer 16

• Induce the switch to IgA
• Induces a wide range of responses including secretion of intergrin α4β7 and chemokines that stimulate migration to the lymph nodes for T cell interaction

Question 17

B and T cell Activation in GALT

Answer 17

• Takes place in payer’s patches, lamina propria, and MLN

- Through MHC I and MHC II