Immunoglobins

Question 1

Our immune system protects us from infection from what species?

Answer 1

Viruses
Bacteria
Protozoans
Helminths
Funghi

Question 2

Two major systems of immunity that work cooperatively. What are they?

Answer 2

Innate

Adaptive

Question 3

What is an antigen?

Answer 3

Any substance which elicits an immune response

Question 4

What is the portion called that is recognised by antibodies?

Answer 4

Epitope

Antigenic determinant

Question 5

Antibodies are also termed as what?

Answer 5

Immunoglobulins

Question 6

Immunoglobulins are present in plasma, tissues, secretions and lymphatuc system. They are the product of the humoral immune system secreted by activated B cells (plasma cells) What are the 5 types of immunoglobulins?

Answer 6

IgG
IgM
IgA
IgD
IgE

They provide recognition function and trigger effector functions

Question 7

What is fragment antigen binding (FAB) responsible for?

Answer 7

Binding antigen

Question 8

What is fragment crystallisable responsible for?

Answer 8

Effector function

Question 9

What are the two types of light chains called?

Answer 9

Lambda and kappa

Question 10

What chain determines the class of antibody?

Answer 10

Heavy chain

Question 11

What is the folded structure in antibody chains called?

Answer 11

Immunoglobulin fold

Heavy chain folded into 4 or 5 globular domains

Question 12

In the heavy chain, what are the 4 or 5 globular domain folds called?

Answer 12

VH
CH1
CH2
CH3
(CH4)

Question 13

What is the CDR?

Answer 13

Complementarity determining region

Question 14

How to the hypervariable loops or CDRs form the antigen binding site?

Answer 14

Form close-lying loops at one end pf the VH domain and VL domain
When the two domains are paired their 6 CDRS lie close together and create the binding site

Question 15

Why does IgM only exist in plasma and secretions and not in tissues?

Answer 15

Its too large

Question 16

What is the major antibody in seromucous secretions (saliva, milk, colostrum)?

Answer 16

Human IgA

Class of antibody first encountered by mnay invading bacteria and viruses

Question 17

What antibody is found in monomeric and dimeric forms?

Answer 17

IgA

Question 18

IgE function is associated with what?

Answer 18

Allergic respsonse and important for protection against parasitic infections

Question 19

What antibody is found in very low serum concentrations?

Answer 19

IgD

Question 20

What is the protective functions of IgS?

Answer 20

Blocking of entry of pathogens into host cells

Neutralisation of toxins

Question 21

What is meant by the term complement?

Answer 21

A very complex system of about 50 different proteins found either in serum or as receptors on white cells

Question 22

What is the process in which activation of classical complement pathway occurs?

Answer 22

Binding of C1q to IgG or IgM activates C1r, which cleaves and activates C1s
Further steps in complement cascade are triggered
Culminates in lysis of target cell

Question 23

What is the difference between free Ig and aggregation of Ig with Fc receptor-mediated clearance?

Answer 23

Free Ig does not cross-link Fc receptors

Agrregation of Ig on bacterial surface results in cross-linking of Fc receptors