Immune Response 4

Front 1

What type of cell present antigens to the adaptive immune system?

Back 1

Phagocytes

Front 2

What is the complement?

Back 2

A protective part of the immune system that helps lymphocytes, antibodies and phagocytes clear pathogens

Front 3

6 things the complement system does

Back 3

1) initiates acute inflammation by stimulating mast cell degranulation

2) attracts neutrophils to infection site by chemotaxis

3) attacks bacterial cell membranes

4) opsonizes bacteria for phagocytes

5) promotes clumping of antigen-bearing agents

6) helps clear immune complexes and cell fragments

Front 4

What's the complement in humans composed of?

Back 4

9 major serum proteins

Front 5

4 points on cascade pathways e.g. ensures specificity

Back 5

Amplifies weak signals

Highly regulated

Prevents inappropriate activation

Generates useful cleavages products

Front 6

What is C1 activated by and what's the effect?

Back 6

C1 is a large serum glycoprotein complex composed of three subunits

Is is activated by immune complexes in serum or on pathogen surface.

It binds non self or bad self cells to bring about agglutination (expression of antigens)

Hint 6

Classical complement activation pathway

Front 7

Example of a classical activation pathway

Back 7

C1 binds to immune complex.

Activates serum protein C4.

C4 binds to cell or pathogen surface and acts as a binding site for C2

This forms a complex which then binds and cleaves C3 into active fragments. (Amplification loop of the c3 cleavage bit for more c3 molecules)

C3b has immunological effects.

Hint 7

Starts with C1

Front 8

What does C3b do? Is it innate or adaptive?

Back 8

It can bind directly or indirectly to microbe and opsonizes it for uptake by phagocyte. Binds to complement receptors on phagocytes.

Can be innate or adaptive.

Front 9

How is the lection pathway different to the classical pathway?

Back 9

Initiated by a mannose binding protein (lectin) rather than immune complexes

Front 10

What do C3a and C5a do in classical, alternate and lectin pathways? (Same in all three)

Back 10

C3a and C5a mediate inflammation through activation of leukocytes.

Front 11

What are cytokines?

Back 11

Small soluble proteins, peptides or glycoproteins that act as signals

Front 12

What do cytokines do?

Back 12

Released by cells in response to a stimulus e.g. immune complexes. Bind to specific cell surface receptors.

Critical for cellular immune processes. Some influence production and growth of leukocytes.

Front 13

4 cellular immune processes that cytokines are critical for

Back 13

- chemotaxis

- cell activation

- enhanced cytotoxicity

- general immune regulation.

Front 14

Cytokines are pleiotropic, redundant and multifunctional. What do these three things mean?

Back 14

Pleiotropic= can act on multiple cell types

Redundant= different cytokines have different functions

Multinational= able to regulate multiple processes

Front 15

5 cytokines groups (inc. other)

Back 15

Monokines

Chemokines

Interferon's

Lymphokines

Other.

Front 16

What are monokines released by and why?

Back 16

Monokines are released by monocytes and macrophages to aid innate responses.

Front 17

When are chemokines produced and why?

Back 17

Produced by various cell types following infection or physical damage.

Activate and direct monocytes and macrophages to damage (e.g. are chemotaxins)

Front 18

When are interferons produced and why?

Back 18

Produced by many cells in response to viral infection.

Inhibit viral replication, increase NK cell activity.

Front 19

What are lymphokines produced by and why?

Back 19

Released primarily by lymphocytes. Act as lymphocyte growth factors and direct lymphocyte development.

Front 20

What are the cytokines produced by T helper cells important for?

Back 20

Those produced as a result of binding to MHC Class II are important for: stimulating killing of intracellular microbes and generation of Tc cells.

Others are important for B cell differentiation and stimulating anti parasite defence by recruitment of eosinophils.

Front 21

Example of an 'other' cytokines, what its produced by and whh

Back 21

Tumour necrosis factor.

Produced by macrophages, dendritic cells and mast cells.

Involved in systematic inflammation.

Front 22

Cleavage of C3 leads to the assembly of what? Which does what?

Back 22

Cleavage of C3 leads to assembly of MAC which punches holes in foreign or dangerous cells to kill them.

Hint 22