L24_Immunity to Microorganisms

Question 1

Where do most bacteria end up dying?

Answer 1

Inside of a phagocyte. YOU NEED PHAGOCYTES OR YOU ARE FUCKKKED!

Question 2

Name six non-specific barriers that the innate immune system uses to help prevent/contain infection.

Answer 2

Skin, pH barriers, Flushing, Lysozyme, Phagocytes, complement

Question 3

How does S. Aureus prevent opsonization by IgG?

Answer 3

Protein A binds to Fc region of IgG and prevents recognition by phagocytic cells.

Question 4

What is the primary adaptive immune response to bacteria?

Answer 4

Antibody

Question 5

What antibody type helps prevent attachment to epithelial surfaces?

Answer 5

IgA

Question 6

Are antibody effective against facultative intracellular parasites?

Answer 6

No, because their job is to get the parasite into the macrophage, but if the parasite can thrive in the macrophage then this does no good.

Question 7

Is the cytoplasm of an activated macrophage toxic?

Answer 7

NO, only the phagosome

Question 8

Do macrophages have antigen receptors?

Answer 8

NO

Question 9

What type of immunity is responsible for clearing facultative intracellular parasites like listeria? Can immunity be transferred with serum?

Answer 9

Cell Mediated Immunity. Immunity cannot be transferred with serum.

Question 10

In cell mediated immunity, the specific immunity is a function of what cells?

Answer 10

T-cells (TH1 CD4 T-Cells)

Question 11

What is the most important macrophage activating factor?

Answer 11

Interferon gamma

Question 12

What is the major immunological difference between someone with Tuberculoid vs Lepromatous Leprosy?

Answer 12

In tuberculoid there is an adequate T-cell response (TH1) where as in the Lepromatous there is hypergammaglobulinemia and low or absent T-cell responsiveness (TH2)

Question 13

What is easier to induce, a TH1 response or a TH2 response?

Answer 13

TH2

Question 14

Can an activated macrophage kill bacteria that are in its cytoplasm?

Answer 14

No because they need to be contained in the phagosome. this is a case where you would kill the macrophage in order to allow immunocompetent macrophages to take up the released bacteria.

Question 15

What helps determine whether a T-cell becomes TH1 or TH2?

Answer 15

How the APC (dendritic cell is perceiving the environment and presenting antigen.

Question 16

Can a CD8 cell kill a parasite or bacterium? Why?

Answer 16

NO. No MHC1 present on cell.

Question 17

What is the major virulence factor of salmonella typhosa?

Answer 17

the ability to survive in an acid environment.

Question 18

List 3 facultative intracellular organisms

Answer 18

Mycobacterium Tuberculosis and Listeria Monocytogenes, mycobacterium leprae

Question 19

Can dead listeria induce CMI, antibody?

Answer 19

Only live listeria can induce CMI. Live or dead can induce antibody production.

Question 20

What cytokine given off by dendritic cells to CD4 T-cells make them tend to become TH1 or TH2

Answer 20

TH1 - IL12

TH2- IL10

Question 21

What type of immunity is most important in clearing parasites?

Answer 21

T-cells

Question 22

how can antibodies help with viral infections?

Answer 22

Bind to viruses and prevent infection

Question 23

What type of immunity is most important in clearing viruses.

Answer 23

T-cell (Specifically CD8)

Question 24

What effects do IFN alpha and Beta have on surrounding cells to help prevent viral spread?

Answer 24

Induce resistance to viral replication in all cells, increase MHC class I expression, activate NK cells to kill virus-infected cells.