Immunity to Infection

Question 1

What are the immune mechanisms used to defend against BOTH bacteria and viruses?

Answer 1

• Neutrophils and Macrophages
• Ab
• Ab with Complement
• Activated Macrophages

Question 2

How do neutrophils and macrophages respond to bacteria/viruses?

Answer 2

Phagocytose and destroy intact organisms

Question 3

How do Ab respond to bacteria/viruses?

Answer 3

Block the adsorption of the organism into the tissue by binding surface Ag

Question 4

How do Ab with complement respond to bacteria/viruses?

Answer 4

Can bind host OR organism Ag to enhance neutrophil and macrophage phagocytosis or lyse the infected host cells

Question 5

How do activated macrophages respond to bacteria/viruses?

Answer 5

Enhance the destruction of the engulfed organism

Question 6

What immune mechanisms are used to combat only viruses?

Answer 6

• CD8 T cells
• NK cells
• Interferons

Question 7

How do CD8 T cells respond to viruses?

Answer 7

Lyse cells that present viral proteins

Question 8

How do NK cells respond to viruses?

Answer 8

Lyse viral infected cells

Question 9

How do interferons respond to viruses?

Answer 9

Target non-infected cells and enhance their anti-viral capabilities

Question 10

What immune mechanism are used to combat only bacteria?

Answer 10

-Ab for toxins

Question 11

What are the mechanisms to attack extracellular bacteria?

Answer 11

Phagocytes and Ab are effective

Question 12

What can be used against gram negative bacteria that are extracellular (Neisseria meningitidis)?

Answer 12

Complement System

Question 13

What can be used against gram positive bacteria that are extracellular (Staphylococcus aureus)?

Answer 13

Opsonization

Question 14

How are bacteria with anti-phagocytotic capsules dealt with (Streptococcus pneumoniae)?

Answer 14

Complement System

Question 15

How are fungi (Candida albicans) dealt with?

Answer 15

Phagocytic cells

Question 16

How are parasites dealt with?

Answer 16

Ab with complement and ADCC via eosinophils

Question 17

Is innate immunity effective against parasites?

Answer 17

NO

Question 18

How are intracellular bacteria/protozoa dealt with?

Answer 18

T cells with Th1

->Innate immune system is ineffective and Ab are INEFFECTIVE

Question 19

How are viruses dealt with?

Answer 19

Usually all forms of immunity are used

Question 20

What is the function of IFN-alpha?

Answer 20

It is made by leukocytes and targets virally infected cells to prevent viral replication

Question 21

What is the function of IFN-beta?

Answer 21

It is made by fibroblasts and targets virally infected cells to prevent viral replication

Question 22

What is the function of IFN-gamma?

Answer 22

Made by T cells and targets macrophages to activate them and up regulates MHC I and II

Question 23

What are the two proteins that IFNs make?

Answer 23

Synthetase

Protein Kinase

Question 24

What is the function of the IFN synthetase?

Answer 24

It catalyzes adenine polymerization and leads to ribonuclease cleavage of viral mRNA

Question 25

What is the function of the IFN protein kinase?

Answer 25

It Pi EIF-2 an initiation factor that causes viral protein mRNA to remain untranslated and increases its cleavage