Antibodies and more immunology Flashcards Preview

Microbiology > Antibodies and more immunology > Flashcards

Flashcards in Antibodies and more immunology Deck (38):
1

Phagocytosis Step 1: Chemotaxis

Chemical attraction of phagocytes to microorganisms
Microbial products (peptidoglaycan, LPS)
Damaged tissue
Cytokines
Complement components

2

Phagocytosis Step 2: Adherence

Attachment of phagocytic membrane to microorganisms or foreign material
Phagocyte receptors - Toll like receptors (TLRs) +Microbe - Pathogen/Danger associated molecular pattern (PAMP or DAMP) Eg. LPS, Peptidoglycan

3

Phagocytosis Step 3: Ingestion

Pseudopods engulf the organism and form phagosome or phagocytic vehicle

4

Phagocytosis Step 4: Digestion

In the cytoplasm Phagosome fuses with in lysosome - Phagolysosome

5

Lysosomal enzymes

Lysozyme, lipase, protease, nuclease
Toxic oxygen radicals through oxidative burst
Myeloperoxidase
Superoxide dismutase

6

Phagocytosis Step 5: Elimination

Residual body

7

Inflammation

Second line of defense
Can be caused by microbes, physical and chemical agents
Host response to tissue damage
Serves to destroy the infectious agent, to confine it, and repair or replace the damage tissue

8

What are the cardinal signs of inflammation?

Redness, pain, heat, swelling, loss of function

9

Intense inflammation and for short periods of time is what kind of inflammation?

Acute inflammation

10

Chronic inflammation is?

Less intense and long lasting inflamation

11

What are the effects of inflammation?

Destroy or limit infection
Repair the damage tissue

12

Fever

Hypothalamus control body temperature
During infection, products of microbes induce the release of cytokines such as interleukin-1 which is an endogenous pyrogen

13

Antimicrobial substances

Complement
Interferons
Iron binding proteins
Antimicrobial peptides

14

Complement

A group of >30 proteins activated as a cascade by a pathogen or by an antigen antibody reaction

15

Complement together action of these proteins destroy microbes by

Enhanced Phagocytosis
Inflammation
Cytolysis

16

What are the three complement pathways?

Classical Pathway
Alternate Pathway
Lectin Pathway

17

Complement classical pathway

Initiated by antigen antibody complexes

18

Initiated by the interaction between C3, factors B, D and P and the pathogen is what pathway

Complement alternate pathway

19

Complement Lectin Pathway

Mannose binding lectin binds to Mannose on the surface of the microbes

20

The end result of the complement cascade is?

Membrane attack complex

21

Opsonin

Coats microbes and enhance phagocytosis (C3b)

22

Anaphylatoxins

Induce release of histamine and result in severe allergic reactions (C3a, C5a)

23

Membrane attack complex

Polymerisation of C5-C9

24

Complement

C1-C9 with C3 being the most critical

25

What is interferon?

A cytokine produced by virus infected cells, lymphocytes

26

What are the three types if interferons?

Interferon alpha
Interferon beta
Interferon gamma

27

Iron binding proteins

In the body iron is bound to molecules such as transferrin, lactoferrin, ferritin, hemoglobin

28

Bacteria that contain siderophores do what?

Sequester iron form the body

29

Which bacteria is more virulent? Ones with or without siderophores?

With siderophores

30

What line of defense is Adaptive immune responses?

Third line of defense

31

Is adaptive immune response specific or nonspecific?

Specific

32

What is adaptive immunity?

Specific immune response induced against a specific pathogen

33

What are the dual nature of adaptive immunity?

Humortal response - Antibody
Cell mediated response - T cells

34

What is an antigen?

Proteins that induce antibody response

35

What is the specific region of an antigen which interacts with antibody

Epitopes (antigenic determinants)

36

What is Hapten?

Low molecular weight compounds which can not induce an antibody response by itself
Attach to a carrier molecule to induce antibody response

37

What are antibodies?

Proteins called immunoglobulins. Produced by a B cell. One antibody molecule has two identical antigen binding sites which binds to antigen epitopes

38

What is valence?

the number of antigen binding sites in an antibody