Lecture 2: Immune Function Flashcards Preview

BIO 320 Immunology > Lecture 2: Immune Function > Flashcards

Flashcards in Lecture 2: Immune Function Deck (22):
1

What are the 3 lines of defense body uses to defend itself against foreign invaders?

1st: Barrier (skin)
2nd: Innate (WBC)
3rd: Adaptive (IgG)

2

What are the characteristics of Barrier Defenses?

Don't specify between microbes
-Can be breached (cuts, ingestion, inhalation)

3

What are the characteristics of Innate immunity?

-Rapid
-Nonspecific
-Leukocytes (phagocytes) like WBC's eat pathogens
-Mainly to hold off pathogen until adaptive immunity kicks in

4

What are the characteristics of Adaptive Immunity?

-Slow
-Highly specific
-Very effective
-Develops response for specific type of pathogen

5

What is the goal of a pathogen? What is the problem? What is the solution?

Goal of pathogen is to reproduce
-Too successful = kill host
-Not successful = kill pathogen

Solution is co-evolution.
-Balanced relationship

6

What is an example of the co-evolution of pathogen/host?

Seasonal Flu
-Population develops adaptive immunity to strain during flu season
-Virus mutation creates new strain
-The population will have partial protection

7

Microbes evolve faster than humans. What problem does this create?

Newly introduced microbes, that the population has not been exposed to, cause MORE SEVERE disease
-We have no immunity and can't evolve fast enough
-This results in more death before adaptive response

8

What is a PAMP?

Pathogen-Associated Molecular Pattern
-Conserved molecules of related microbes that are recognized by INNATE immune cells
-More general
-Looks for similar microbes that are DANGEROUS & FOREIGN

9

What is an Antigen?

Specific Molecules that differentiate microbes and are recognized by ADAPTIVE immune cells
-Most antigens recognized by adaptive immune cells are proteins
-Key & Lock mechanism
-Looks for FOREIGN microbes only

10

How do we recognize and differentiate different pathogens?

PAMPs and Antigens

11

What is the difference between extracellular and intracellular pathogens?

Extracellular
-Colonize surfaces
-Circulate in fluids
-Replicate outside of host

Intracellular
-Invade host cells
-Replicate within host

12

What are the types of extracellular and intracellular pathogens?

Extracellular
-Bacteria, Fungi, and Parasites

Intracellular
-Viruses

13

What are characteristics of bacteria pathogens?

Simple
Unicellular
Prokaryotic (No nucleus)

14

How do bacterial cell walls differ?

Peptidoglycan

Gram Positive
-Thick with Peptidoglycan

Gram Negative
-Thin with little peptidoglycan
-Produce Lipopolysaccharides which is a PAMP

15

Are bacteria extracellular or intracellular or both?

Both
-Most exist as extracellular pathogens but some reproduce as intracellular

16

What are the characteristics of Fungi pathogens?

Complex, unicellular, eukaryotic (true nucleus)
-Most are extracellular pathogens

17

What are the characteristics of Parasite pathogens?

Most are extracellular

Two Types:
1) Unicellular Eukaryotic microbes (protozoa)
2) Multicellular Eukaryotic animals (helminths)

18

What are the characteristics of viruses?

Acellular infectious particles
-Nucleic acid genome (dsRNA PAMP)
-Protein coat (antigen)
-Obligate intracellular (host needed for repro)

19

How do PRRs and PAMPs work as part of innate immunity ?

Recognize harmful vs nonharmful
-Pattern recognition Receptors (PRR) detect Pathogen associated Molecular Patterns (PAMP)
-The cell will release Cytokines which trigger inflammatory response

20

How do cytokines help immune reponse?

Cytokines signal immune response
-Results in increased blood flow to site of infection
-Gets more WBC's to site

21

How do Antigens and Antigen receptors work as part of the adaptive immune system?

B-cell Receptors (BCR) and T-cell Receptors (TCR) will bind to an antigen
-Helper Tcell will transmit a chemical signal
-Becomes Plasma cell and releases antibodies

22

Development, Surveillance, Recruitment, and Elimination are the steps of the immune response. Explain.

Development
-Immune Cells develop/mature in the bone marrow
-T Cells mature in the thymus

Surveillance
-Immune cells patrol the body

Recruitment
-When immune cells find trouble they use cytokines to recruit others to fight

Elimination
-Effector cells used to kill the infection