Innate and Adaptive Immunity

Question 1

Immunity

Answer 1

host reaction to an antigen

Question 2

Immune system

Answer 2

the cells and molecules which are responsible for immunity

Question 3

Immune response

Answer 3

individual responses of an immune system to foreign substances

Question 4

Innate immunity (natural immunity)

Answer 4

consists of rapid defense mechanisms already present; non-specific; do not discriminate self/nonself
cells involved: phagocytes (neutrophils/ macrophages/ monocytes), eosinophils and NK cells

Question 5

Adaptive immunity (acquired immunity)

Answer 5

consists of delayed defense mechanisms; specific for particular antigen; induced or stimulated by exposure to a foreign substance
cells involved: B cells, T cells

Question 6

Antigen

Answer 6

any substance that is recognized as foreign when introduced into the body

Question 7

How can an antigen not be an immunogen?

Answer 7

too small, not recognized by the body as foreign, does not elicit an immune response

Question 8

What are the anatomical and physical barriers of the innate immune system?

Answer 8

skin, mucous membranes, saliva, temperature, low pH, chemical mediators

Question 9

What cells and molecules make up the innate immune system?

Answer 9

cells involved: phagocytes (neutrophils/ macrophages/ monocytes), eosinophils and NK cells

Question 10

Where do the cells and molecules of the innate immune system reside?

Answer 10

surface, subsurface

Question 11

What receptors are important for antigen recognition in the innate immune system?

Answer 11

pathogen associated molecular patterns are recognized by pattern recognition receptors

Question 12

What are PAMPs and PRRs?

Answer 12

PAMPs- pathogen associated molecular patterns
PRRs- pattern recognition receptors
PRRs on cells recognize PAMPs

Question 13

What are some examples of PAMPs and PRRs and what they recognize?

Answer 13

PAMPs- unmethylated DNA; mannose; LPS

PRRs- TLR9; mannose receptors; TLR2

Question 14

What are acute phase proteins? Examples? Role in immunity?

Answer 14

proteins with up-regulated or down-regulated expression during acute inflammation; ex.- opsonins, activators of complement

Question 15

Is previous exposure necessary for an effective response of the innate immune system? Why or why not?

Answer 15

No, no memory; happens with first exposure

Question 16

What cells and molecules make up the adaptive immune system?

Answer 16

B cells (IgM, IgG, IgE, IgA, IgD) and T cells (T lymphocytes)

Question 17

What receptors are important for antigen recognition in the adaptive immune system?

Answer 17

antigen presented in the context of MHC II on APC (B cells, dendritic cells, macrophages)

Question 18

Where do the cells and molecules of the adaptive immune system reside?

Answer 18

originate in bone marrow, mature in primary lymphoid organs, functional in secondary lymphoid organs

Question 19

Is previous exposure necessary for effective response in the adaptive immune system? Why or why not?

Answer 19

yes; use of B cells; takes long time initially but amanestic response is more rapid on secondary exposure to same antigen

Question 20

Compare and contrast the timing and effectiveness of the primary and secondary immune responses.

Answer 20

primary (adaptive)- delayed, days-weeks

secondary (adaptive/amanestic)- faster and stronger due to memory B cells

Question 21

How do eosinophils and NK cells act in both the innate and acquired immune systems?

Answer 21

innate: initial response to foreign material; NK-> recognize lack of MHC I on nucleated cells
adaptive: use of antibody receptors to recognize cells to destroy

Question 22

Understand the chronology and events during the immune response to an invading microbe.

Answer 22

Innate: 0-4 hours
Primary adaptive: 4-96 (days to weeks)
Secondary (amanestic) adaptive: >96, more rapid response that primary adaptive when responding to secondary exposure to previously seen antigen