- antibodies - complement molecules - circulating proteins

Lecture 15 Flashcards by Tendai Gwata

Innate System: Second Line of Defence

Soluble Components

Plasma proteins
cytokines
Interferons

How well did you know this?

Not at all

Perfectly

How does the body respond to invasion

▪ Recognition

▪ Attack

How well did you know this?

Not at all

Perfectly

How does the body recognize an invasion

PAMPs
DAMPs
Sometimes Opsonization

How well did you know this?

Not at all

Perfectly

PAMPs

Essential to microbial survival and metabolism
which makes them relatively invariant and
evolutionary stable

How well did you know this?

Not at all

Perfectly

Give me examples of PAMPs

-Peptidoglycan
-LPS
-Mannose
-Nucleic acids
Flagellin
Non-methylated CpG repeats

How well did you know this?

Not at all

Perfectly

TOLL-LIKE RECEPTORS: PATHWAY

-Recognize the PAMPS
-Cascade occurs
Activation of transcription factors
-Increased expression of cytokines

How well did you know this?

Not at all

Perfectly

What are ways the innate immune system attacks

Phagocytosis
Opsonization
Secretions

How well did you know this?

Not at all

Perfectly

What is the general activity of phagocytes

To suvey
-To ingest
-To o extract immunogenic
information from foreign
matter

How well did you know this?

Not at all

Perfectly

Professional Phagocytes

Neutrophils

- Macrophages

How well did you know this?

Not at all

Perfectly

Non-Professional phagocytes

Lymphocytes, NK cells, Epithelial cells, Endothelial cells,

Fibroblast

How well did you know this?

Not at all

Perfectly

What is Opsonization

to ensure
cell is readily identified, and
more efficiently taken by
phagocytes

How well did you know this?

Not at all

Perfectly

What receptors are used for opsonization

✓CR1 – complement receptor
for C3b fragment
(complement cascade)
✓Fc receptors for Fc region of
immunoglobulins
(antibodies)

How well did you know this?

Not at all

Perfectly

Main opsonin for the antibodies

IgG

How well did you know this?

Not at all

Perfectly

What’s special about IgM

-There are no Fc receptors for IgM but IgM activates the complement system for opsonization

How well did you know this?

Not at all

Perfectly

What are the main complement opsonin’s

C3b, C4b, and C1q

How well did you know this?

Not at all

Perfectly

How do the complement molecules opsonize

Opsonize the antigen

- Opsonized antigen binds to CR1 receptor on the phagocyte

How well did you know this?

Not at all

Perfectly

Name three opsonin’s

antibodies
complement molecules
circulating proteins

How well did you know this?

Not at all

Perfectly

Microbial degradation within the phagolysosome occurs

along two pathways:

Oxygen dependent

- Oxygen independent

How well did you know this?

Not at all

Perfectly

Describe Oxygen-dependent degradation: (Oxidative Burst)

Study These Flashcards

NADPH oxidase produces superoxide which
recombines with other molecules to produce reactive
free radicals
✓ Superoxide anions are then used by superoxide
dismutase to produce hydrogen peroxide
✓ Myeloperoxidase uses the derived hydrogen peroxide
to produce hypochlorite or bleach (second most
important enzyme)

What happens when there is a defeciency in NADPH oxidase

Study These Flashcards

Absence of NADPH
oxidase will prevent
the formation of
reactive oxygen species
and will result in
chronic granulomatous
disease (CGD)

What type of infections are associated with NADPH defeciencies

Study These Flashcards

catalase
positive infections
(Candida, Serratia, H. pylori,
Actinomyces, Pseudomonas, E. coli, S. aureus)

Common symptoms of CGD

Study These Flashcards

Mouth ulcers
Neutrophil function impaired
Pneumonia
Menningitis
Abcess
Cellucitis

nitroblue tetrazolium test

Study These Flashcards

Blue -Normal

Yellow -abnormal

▪ Dihydrorhodamine 123

Study These Flashcards

Two peaks - normal

One peak -abnormal

Chediak-Higashi Syndrome

autosomal recessive disorder that arises from a mutation of a lysosomal trafficking regulator protein (Microtubule dysfunction) leading to lack of phagolysosome formation. -Large lysosomes in the phagocytes

Chediak-Higashi Syndrome presentation

- Albinism - Neutropenia - Peridontal disease - reccurent infections - Hepatomagly - Anemias

Principal cells involved in inflammation

- Macrophages | - Neutrophils

Role of cytokines in inflammation

Secreted to attract leukocytes to the site

Role of histamine in inflammation

causes vasodilation, increased vessel | permeability (redness and heat)

What does swelling during an immune response do

Contains the infection

What stimulates pain receptors

Bradykinin

Resolution/Scar formation

macrophages clean the area; fibroblasts form granulation tissue – lymphocytes mediate long-term immunity

Diapedesis

migration of cells out of blood vessels into the tissues

Chemotaxis

migration in response to specific chemicals at the site of injury or infection

Name 4 cell adhesion molecules

- Selectins - Mucins - Integrins - ICAMS

Leukocyte Extravasation

- Rolling - Activation - Arrest/Adhesion - Transendothelial migration

Leukocyte Adhesion Defect (LAD)

``` Deficiency of the β-2 integrin subunit (CD18) -neutrophils cannot extravasate and fight against bacteria in tissues ```

Hallmarks of LAD

Recurrent skin infections, delayed umbilical separation, absence of pus

Extravasation - Rolling

Mediated by binding of selectins (endothelium) to | mucin-like CAMs (leukocyte)

Extravasation-Activation

Chemokine binding induces conformational change in | integrins (leukocyte)

Extravasation- Arrest/Adhesion

Integrins now capable of binding Ig-superfamily CAMS | endothelium

Transendothelial migration

Migration through tight junctions of inflamed | endothelium

``` what is β-2 integrin subunit (CD18) involved in ```

formation of the β-2 integrins by dimerization | with different CD11 subunits

Inflammatory Process: | Systemic Acute Phase Response

``` Mediated by IL-1, IL-6, TNFα • Act on hypothalamus: fever • Act on liver: ↑ Acute phase proteins (C reactive protein) • Act on bone marrow: ↑ Leukocytosis(left shift and increase in immature cells ) ```

Chronic Inflammatory response

- 2 weeks or longer - successful acute inflammatory response - IFNy and TNFα play a major role

Lecture 15 Flashcards

(45 cards)