Lecture 3

Question 1

An antigen is?

Answer 1

a part of an organism or substance that is recognized by the immune system as non-self
-often cell-surface protein or sugar

Question 2

Passive immunity

Answer 2

• preformed antibody acquired from an outside source

- half-life of ~21 days

Question 3

Non-specific Immunity (Anatomical Defences)

Answer 3

• Skin/Hoof/Hair, mucous membranes
• mucus
• Cilia
• Lacrimal secretions

Question 4

Non-specific immunity(Humoral defences)

Answer 4

• play a role in inflammation
• complement system
• cytokines
• lysozyme

Question 5

Lysozymes function? found in?

Answer 5

Found in tears

-breaks down the cell wall of bacteria

Question 6

Cytokines are?

Answer 6

communication molecules

Question 7

The three roles of the complement system include?

Answer 7

complement fixation
opsonisation
trigger inflammatory reaction

Question 8

Complement fixation

Answer 8

binding to and destroying foreign cell membranes

Question 9

Opsonisation

Answer 9

tagging of foreign cells for stimulation of phagocytosis

Question 10

Non-specific Immunity(cellular defences)

Answer 10

phagocytes

• lack memory
• contribute to inflammatory response

Question 11

Neutrophils

Answer 11

• WBC
• PMNSs
• ingest and digest foreign particles by lysozyme digestion
• very non-specific

Question 12

Neutrophils attracted to sites of infection and inflammation by?

Answer 12

chemotaxis

-chemical signaling from cytokines and interleukins

Question 13

Neutrophil activation

Answer 13

become sticky, marginate in circulation, squeeze through endothelial junctions(diapedesis) and migrate to the site of infection or tissue damage

Question 14

Neutrophils are specifically important in?

Answer 14

mammary glands and uterus

Question 15

Monocytes

Answer 15

largest WBC
5-8%
cytoplasm contains lysosomes
eventually leave circulation to become macrophages in tissue

Question 16

Function of monocytes

Answer 16

non-specific removal of bacteria, fungi, necrotic debris and act as antigen presenting cells to T lymphocytes

Question 17

Humoral wing of the immune system

Answer 17

B cells

production of specific antibodies

Question 18

Cell mediated specific immune system

Answer 18

• macrophages
• tcells
• cytokines

Question 19

B lymphocytes mature in the?

Answer 19

bone marrow

Question 20

T lymphocytes mature in the?

Answer 20

mature in thymus

Question 21

Antibody production by B lymphocytes

Answer 21

• B cell divides repeatedly
• forms a clone of antibody secreting plasma cells
• after assault is over some become memory B cells

Question 22

Types of immunoglobulins(antibodies)

Answer 22

• proteins produced by B cells(plasma cells)
• antigent-antibody complexes stimulate additional production of antibody
• IgG, IgA, IgM, IgE

Question 23

IgA

Answer 23

found on mucosal surfaces
-GI, respiratory, reproductive tracts
10-15% of total

Question 24

IgM

Answer 24

circulates mainly in blood, not tissue
generally produced most quickly in response to antigenic stimulation
-first to scene first to leave
5-10%

Question 25

IgG

Answer 25

most common(80%)
found equally in circulation and in tissue
has the longest half-life of all the antibody types
gives us titres

Question 26

IgE

Answer 26

associated with parasites and allergies

Question 27

Function of antibodies

Answer 27

released into the intercellular fluid where they bind to the infecting antigen and flag it for destruction by phagocytes and complement system
coating may prevent attachement or invasion of bacteria or virus
blind toxins secreted by pathogens

Question 28

What is needed to protect phagocytes from oxidative damage from radicals generated in digestion?

Answer 28

• vitamins E and A
• Selenium
• copper

Question 29

Immunize

Answer 29

to stimulate/confer a protective immune response

Question 30

Modified live vaccine

Answer 30

lab-attenuated virus
produce a low-level true infection
replicates in host
activates both humoral and cell mediated adaptive immunity

Question 31

killed virus vaccines

Answer 31

completely inactivated
all that’s residing in the outside surface of the virus
no replication
adjuvants added to increase immune response
only targets humoral adaptive immune system

Question 32

Advantages of Killed Virus

Answer 32

generally stimulate good humoral response
can be used in all stages of lactation
no risk of shedding
no risk of reversion to virulence
properly stored a partial bottle can be used

Question 33

Disadvantages to Killed virus vaccines

Answer 33

primer dose needs to be boostered in 2-4 weeks
ability to stimulate CMI?
antibodies alone are not protective for many diseases
antibodies produced against strains in the vaccine
more expensive
high levels of antibody for approx 4-6 months

Question 34

Advantages of modified live vaccines

Answer 34

stimulate cell mediated and humoral wings of the immune system 
single dose usually provides protection
less expensive per dose
more rapid immune response
longer lasting protection

Question 35

Disadvantages to Modified live vaccine

Answer 35

historically cannot be given to pregnant animals
can be inactivated by heat, sunlight, chemical residues in syringe
must be used within hours

Question 36

Onset of immunity is typically?

Answer 36

2-4 weeks after vaccination

Question 37

Compliance for vaccination success?

Answer 37

storage and transportation
mixing, usage, maintenance of sterility
correct route of administration
accurate records to vaccinate all animals at correct times
testing and vaccination of purchased animals