7. The Antibody Response

Question 1

What class(es) of antibody are produced as a result of stimulation of the immune system with lipopolysaccharide (LPS), and why?

Answer 1

• LPS is a T-independent Ag which means that it stimulates T cell independent Ab response
• T cell independent Ab response results in production of IgM only

Question 2

How do B cells recognize antigens?

Answer 2

• recognize plain antigens with their B cell receptor

Question 3

How do T cells recognize antigens?

Answer 3

• recognize Ag bound to MHC molecule with their T cell receptor

Question 4

What cells in the immune system can function as antigen processing cells (APC)?

Answer 4

• Macrophages
• Dendritic cells
• certain B cells
• langerhans cells

Question 5

How are antigens processed in the T cell-dependent antibody response?

Answer 5

1. Extracellular Ag is taken into the cell
2. Ag is partially degraded by lysosomes
3. MCH II is synthesized
4. MCH II vesicle fuses with peptide-containing vesicle
5. MHC-peptide complex is presented on cell surface

Question 6

What is the function of IL-1, and what cell produces this cytokine?

Answer 6

• produced by macrophage and dendritic cells

- induces resting T helper cell to become activated T helper cell

Question 7

What is the function of IL-2, and what cell produces this cytokine?

Answer 7

• activate T helper cell

- causes T helper cell to proliferate

Question 8

What cytokines stimulate B cells to proliferate? to differentiate into plasma cells?

Answer 8

Proliferation stimulated by: IL-2, IL-4, IL-5

Differentiation stimulated by: IL-6