Flashcards

Question 1

Macrophage

Answer 1

Long-lived phagocyte that eats microbes and dead cells, also calls in reinforcements with cytokines.

Question 2

Mast cell

Answer 2

Skin/mucosa sentinel that dumps histamine, cytokines, and lipids fast to trigger inflammation and allergy-like responses.

Question 3

Monocyte

Answer 3

Blood-circulating precursor that turns into macrophages or dendritic cells when it enters tissues.

Question 4

Natural Killer (NK) Cell

Answer 4

Innate lymphocyte that kills virus-infected or tumor cells without needing prior sensitization.

Question 5

Dendritic Cell

Answer 5

Professional antigen-presenter that captures antigens and activates naïve T-cells.

Question 6

B-Lymphocyte

Answer 6

Adaptive cell that differentiates into plasma cells to pump out antibodies

Question 7

T-Lymphocyte

Answer 7

Adaptive cell that either kills infected cells (CD8+) or orchestrates immune responses (CD4+).

Question 8

Neutrophil Granulocyte

Answer 8

Short-lived “first responder” that swarms to infection, phagocytoses, and releases toxic granules.

Question 9

Eosinophil Granulocyte

Answer 9

Specialized killer of parasites and modulator of allergic inflammation.

Question 10

Basophil Granulocyte

Answer 10

Rare granulocyte that amplifies allergic responses by releasing histamine and IL-4.

Question 11

Type I Interferons

Answer 11

Inteferons: α & β

Secreted by virus-infected cells (plasmacytoid dendritic cells are super producers)

Accumulate in T-cell zones in lymph nodes after infection.

https://prnt.sc/UG-_ELDnHT3A

Question 12

Interferon-γ

Answer 12

Macrophage-activating cytokine secreted by NK cells and T helper cells

Question 13

TNF & IL-1

Answer 13

Activate endothelial cells

Stimulate chemokine prod.

Increase neutrophil prod. by the bone marrow

Induce IL-6 prod.

Question 14

TNF, IL-1, IL-6

Answer 14

Endogenous Pyrogens

Fever (inc. temp. @ hypothalamus)

APP synthesis (@ liver)

Question 15

IL-12

Answer 15

Stim. the prod. of the macrophage activating cytokine (IFN-γ) by NK cells & T-cells

Question 16

CD3 Function

Answer 16

TCR——Antigen-MHC
↓
↓ (Phos. by Kinases)
↓
ITAM—-Pi
↓
↓ (+)
↓
IC Signalling cascade
↓
↓ (+)
↓
T-cell activation

Question 17

IL-2

Answer 17

Central growth factor for T-cells

Question 18

T-Helper-2 (Th2)

Answer 18

• Anti-parasites
• (+) Mast Cells
• (+) Basophils
• (+) Eosinophils
• IL-4 (Pushes B-cells to make IgE; allergy)

Question 19

T-Helper-17 (Th17)

Answer 19

• EC Pathogens
• Inflammation
• (+) Neutrophils
• IL-17

Question 20

Follicular Helper T-Cells

Answer 20

• Isotype switching of B cells
• IL-21

Question 21

Regulatory T-Cells

Answer 21

• Peripheral tolerance
• Recognize MHC peptide complexes (self)
• Prod. cytokines to supress immune response

Question 22

Positive costimulators

Answer 22

CD28—B7
CD40L—CD40
ICOS—ICOS-L

Question 23

Negative costimulators

Answer 23

CTLA-4—B7
PDA1—PD1L

Question 24

CD28—B7 Function

Answer 24

Initiation of immune responses

Question 25

ICOS---ICOS-L Function

Answer 25

T-cell help in germinal center reactions (antibody responses)

Question 26

CTLA-4---B7 Function

Answer 26

Inhibits early T cell responses in lymphoid organs

Question 27

PD-1:PD-L1,2 Function

Answer 27

Inhibits effector T cell responses in peripheral tissues

Question 28

Fc region can activate?

Answer 28

1. Inflammatory & effector functions of cells 2. Inflammatory & effector functions of complement 3. Trafficking of antigens into the antigen processing pathways

Question 29

IL-21

Answer 29

Control B-cell survival, proliferation, differentiation and isotype switching

Question 30

IgG

Answer 30

* Most abundant * Activates Fc receptors + complement (Opsonization, ADCC) * Crosses placenta

Question 31

IgM

Answer 31

* First responder * Pentamer * Complement activator * Microbe agglutination * Monomeric: B-Cell receptor

Question 32

IgA

Answer 32

* Mucosal secretions * Dimer * Mucosal defense

Question 33

IgE

Answer 33

* Parasite defense * Allergic reactions * Binds mast cells & basophils (degranulation for histamine release)

Question 34

IgD

Answer 34

* Trace levels * acts as B-cellr eceptor with IgM

Question 35

Vascular changes of inflammation

Answer 35

* Vasodilation * Increase vascular permeability * increased adhesion of WBCs

Question 36

Cellular events of inflammation

Answer 36

* Recruitment (& activation) of Neutrophils and Monocytes

Question 37

Cytokines secreted by macrophages during inflammation

Answer 37

**IL-1** * (+) Endothelium, lymphocytes * (+) Fever * (+) access of immune cells **TNF-α** * (+) vascular permeability * (+) Swelling & fluid entry * (+) IgG * (+) Complement sys. * Can cause shock of systemic **IL-6** * (+) B-cell AB prod. * (+) APP from liver * (+) Fever **IL-8** * Chemoattractant * (+) Neutrophils, basophils, T-cells **IL-12** * (+) NK Cells * (+) Th1 differentiation

Question 38

Mast Cell Response

Answer 38

**Receptors** * FcεRI * TLR **Seconds response** * Histamine * TNF-α * Tryptaste * Chymase **Minutes response** * Leukotrienes * Prostaglandins **Hourly response** * TNF-α * IL-4 * IL-5 * IL-6

Question 39

Early steps of compement pathways

Answer 39

https://prnt.sc/VDwaSI4iIS-Y

Question 40

Neutrophil migration pathway

Answer 40

**Margination & rolling** * (E,P) Selectins bind sialyl-Lewis on neutrophils for rolling contact * Triggered by Histamine, Thrombin, TNF, IL-1 **Adhesion** * Chemokines (IL-8) (+) neutrophil integrins (LFA-1) bind to ICAM-1 on endothelium * Rolling stops; cells stick **Transmigration/diapedesis** * Neutrophil squeezes b/w endothelial cells via CD31 (enters tissue) **Chemotaxis** * Follows IL-8 chemical gradient to move to infectious site

Question 41

Pro-inflammatory (M1) Macrophage

Answer 41

Secrete: * ROS * NO * Lysosomal Enzymes * IL-1 * IL-12 * IL-23 * Chemokines

Question 42

Anti-inflammatory (M2) Macrophage

Answer 42

Secretes: * IL-10 * TGF-Beta * Proline * Polyamine * TGF-Beta Wound repair, fibrosis, anti-inflammatory effects