L24_Immunity to Microorganisms Flashcards Preview

Microbiology > L24_Immunity to Microorganisms > Flashcards

Flashcards in L24_Immunity to Microorganisms Deck (24):
1

Where do most bacteria end up dying?

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

2

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

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

3

How does S. Aureus prevent opsonization by IgG?

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

4

What is the primary adaptive immune response to bacteria?

Antibody

5

What antibody type helps prevent attachment to epithelial surfaces?

IgA

6

Are antibody effective against facultative intracellular parasites?

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.

7

Is the cytoplasm of an activated macrophage toxic?

NO, only the phagosome

8

Do macrophages have antigen receptors?

NO

9

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

Cell Mediated Immunity. Immunity cannot be transferred with serum.

10

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

T-cells (TH1 CD4 T-Cells)

11

What is the most important macrophage activating factor?

Interferon gamma

12

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

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)

13

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

TH2

14

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

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.

15

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

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

16

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

NO. No MHC1 present on cell.

17

What is the major virulence factor of salmonella typhosa?

the ability to survive in an acid environment.

18

List 3 facultative intracellular organisms

Mycobacterium Tuberculosis and Listeria Monocytogenes, mycobacterium leprae

19

Can dead listeria induce CMI, antibody?

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

20

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

TH1 - IL12
TH2- IL10

21

What type of immunity is most important in clearing parasites?

T-cells

22

how can antibodies help with viral infections?

Bind to viruses and prevent infection

23

What type of immunity is most important in clearing viruses.

T-cell (Specifically CD8)

24

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

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