Immunity And Infection

Question 1

What are the 3 lines of defence

Answer 1

1st line - skin and mucous membranes
2nd line - inflammation (non-specific, natural, innate immunity, rapid responses)
3rd line - immunity (specific, acquired immunity, adaptive, slow response)

Question 2

What is the immune system?

Answer 2

Protects the body from injury, harmful agents or infectious organisms through a system of networks called the host defence system:

• physical and chemical barriers (1st line)
• inflammatory response (2nd line)
• immune response (3rd line)

Question 3

What’s involved in immunity?

Answer 3

• bone marrow
• thymus gland
• lymph nodes
• spleen/tonsils

Question 4

What’s cell mediated immunity?

Answer 4

• CD8 T Cell - natural killer cells - release perforin (MAC) Autolysis
  releases lymphotoxin (DNA) apoptosis
• CD4 T Cell - manages and co-ordinates the immune response:
  As a helper cell it increases production of T and B cells
  Activate CD8 cells into killer T cells
  Activate B cells to mature plasma cells
  Act as suppressor cells, slows immune response

Question 5

What’s humoral immunity?

Answer 5

• B cells mature into plasma cells in bone marrow
• B cells activated by helper T cells and mature into plasma cells
• plasma cells produce immunoglobulin that interact with specific antigens

Question 6

What do both cell mediated and humoral immunity produce.

Answer 6

Memory cells

Question 7

What actions do antibodies (immunoglobulin) do?

Answer 7

• agglutination
• precipitation
• neutralisation
• lysis
• opsonisation
• activation of complement cascade

Question 8

What’s infection?

Answer 8

• extension of inflammatory and immune processes

- complication of immune function

Question 9

What’s infectious disease?

Answer 9

A state of tissue destruction resulting from invasion by micro- organisms

Question 10

Infection terminology

Answer 10

• host - individual exposed to, or contracts the infection
• residential flora - microorganisms that live on or within the body in non sterile areas without causing harm such as skin, mucous membranes, bowel, rectum and vagina
• pathogen - a disease producing micro-organism

Question 11

What are the clinical manifestations?

Answer 11

• inflammatory and immune responses
• pain
• heat
• redness
• swelling
• lymphadenopathy
• loss of function
• purulent exudate
• fever
• malaise
• weakness
• anorexia
• headache
• nausea